Rev.4.2_01
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz,
PWM CONTROL or PWM/PFM SWITCHABLE
SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series
Seiko Instruments Inc. 1
The S-8355/56/57/58 Series is a CMOS step-up switching regulator
controller which mainly consists of a reference voltage source, an
oscillation circuit, an error amplifier, a phase compensation circuit, a PWM
control circuit (S-8355/57 Series) and a PWM/PFM switching control circuit
(S-8356/58 Series).
With an external low-ON-resistance Nch Power MOS, this product is ideal
for applications requiring high efficiency and a high output current.
The S-8355/57 Series realizes low ripple, high efficiency, and excellent
transient characteristics due to its PWM control circuit whose duty ratio
can be varied linearly from 0 to 83% (from 0 to 78% for 250 kHz, 300 kHz,
and 600 kHz models), an excellently designed error amplifier and a phase
compensation circuits.
S-8356/58 Series features a PWM/PFM switching controller that can
switch the operation to a PFM controller with a duty ratio is 15% under a
light load to prevent a decline in the efficiency due to the IC operating
current.
Features
• Low voltage operation : Startup at 0.9 V min. (IOUT = 1 mA) guaranteed
• Low current consumption : During operation 25.9 µA (3.3 V, 100 kHz, typ.)
During shutdown 0.5 µA (max.)
• Duty ratio : Built-in PWM/PFM switching control circuit (S-8356/58 Series)
15 to 83% (100 kHz models)
15 to 78% (250 kHz, 300 kHz, and 600 kHz models)
• External parts : Coil, diode, capacitor, and transistor
• Output voltage : Selectable in 0.1 V steps between 1.5 and 6.5 V (for VDD / VOUT separate types)
Selectable in 0.1 V steps between 2.0 and 6.5 V (for other than VDD / VOUT separate types)
• Output voltage accuracy : ±2.4%
• Oscillation frequency : 100 kHz, 250 kHz, 300 kHz, 600 kHz selectable
• Soft start function : 6 ms (100 kHz, typ.)
• Shutdown function
Applications
• Power supplies for portable equipment such as digital cameras, electronic notebooks, and PDAs
• Power supplies for audio equipment such as portable CD / MD players
• Constant voltage power supplies for cameras, VCRs, and communications devices
• Power supplies for microcomputers
Packages
Drawing Code
Package Name Package Tape Reel
SOT-23-3 MP003-A MP003-A MP003-A
SOT-23-5 MP005-A MP005-A MP005-A
SOT-89-3 UP003-A UP003-A UP003-A
6-Pin SNB(B) BD006-A BD006-A BD006-A
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
2
Block Diagrams
(1) S-8357/58 Series B, H and F Types
(Without Shutdown Function)
(2) S-8357/58 Series B, H, F and N Types
(With Shutdown Function)
VOUT
EXT
VSS
PWMcontrol circuit or
PWM / PFM swiching
control circuit
Oscillation circuit
Soft start built-in
reference power
supply
Phase
compensation
circuit
IC internal
power supply
+
−
VOUT
VSS
EXT
Phase
compensation
circuit
Soft start built-in
reference power
supply
PWMcontrol circuit or
PWM / PFM swiching
control circuit
Oscillation circuit
OFF/ON
IC internal
power
supply
+
−
Figure 1 Figure 2
(3) S-8357/58 Series E, J, G and P Types
(VDD / VOUT Separate Type)
(4) S-8355/56 Series K, L, M and Q Types
(With Shutdown Function, VDD / VOUT Separate Type)
EXT
VSS
Oscillation circuit
PWMcontrol circuit or
PWM / PFM swiching
control circuit
Soft start built-in
reference power
supply
VOUTVDD
Phase
compensation
circuit
IC internal
power
supply
+
−
EXT
VDD VOUT
VSS
Oscillation circuit
PWMcontrol circuit or
PWM / PFM swiching
control circuit
+
−
Soft start built-in
reference power
supply
Phase
compensation
circuit
IC internal
power
supply
OFF/ON
Figure 3 Figure 4
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 3
Product Name Structure
The control system, product types, output voltage, and packages for the S-8355/56/57/58 Series can be selected at the
user’s request. Please refer to the “3. Product Name” for the definition of the product name and “4. Product Name List”
for the full product names.
1. Function List
(1) PWM Control Products
Table 1
Product Name
Switching
Frequency
kHz
Shutdown
Function
VDD / VOUT
Separate
Type
Package Application
S-8355KxxMC 100 Yes Yes SOT-23-5
Applications requiring variable output voltage
and a shutdown function
S-8355LxxMC,
S-8355LxxBD 250 Yes Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage,
a shutdown function, and a thin coil
S-8355MxxMC,
S-8355MxxBD 300 Yes Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage,
a shutdown function, and a thin coil
S-8355QxxMC,
S-8355QxxBD 600 Yes Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage,
a shutdown function, and a thin coil
S-8357BxxMC 100 Yes − SOT-23-5 Applications requiring a shutdown function
S-8357BxxMA 100 − − SOT-23-3 Applications not requiring a shutdown function
S-8357BxxUA 100 − − SOT-89-3 Applications not requiring a shutdown function
S-8357ExxMC 100 − Yes SOT-23-5
Applications in which output voltage is
adjusted by external resistor
S-8357FxxMC,
S-8357FxxBD 300 Yes − SOT-23-5,
6-Pin SNB(B)
Applications requiring a shutdown function
and a thin coil
S-8357GxxMC,
S-8357GxxBD 300 − Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage
and a thin coil
S-8357HxxMC,
S-8357HxxBD 250 Yes − SOT-23-5,
6-Pin SNB(B)
Applications requiring a shutdown function
and a thin coil
S-8357JxxMC,
S-8357JxxBD 250 − Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage
with an external resistor and a thin coil
S-8357NxxMC,
S-8357NxxBD 600 Yes − SOT-23-5,
6-Pin SNB(B)
Applications requiring a shutdown function
and a thin coil
S-8357PxxMC,
S-8357PxxBD 600 − Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage
with an external resistor and a thin coil
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
4
(2) PWM / PFM Switching Control Products
Table 2
Product Name
Switching
Frequency
kHz
Shutdown
Function
VDD / VOUT
Separate
Type
Package Application
S-8356KxxMC 100 Yes Yes SOT-23-5
Applications requiring variable output voltage
and a shutdown function
S-8356LxxMC,
S-8356KxxBD 250 Yes Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage,
a shutdown function, and a thin coil
S-8356MxxMC,
S-8356MxxBD 300 Yes Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage,
a shutdown function, and a thin coil
S-8356QxxMC,
S-8356QxxBD 600 Yes Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage,
a shutdown function, and a thin coil
S-8358BxxMC 100 Yes − SOT-23-5 Applications requiring a shutdown function
S-8358BxxMA 100 − − SOT-23-3 Applications not requiring a shutdown function
S-8358BxxUA 100 − − SOT-89-3 Applications not requiring a shutdown function
S-8358ExxMC 100 − Yes SOT-23-5
Applications in which output voltage is
adjusted by external resistor
S-8358FxxMC,
S-8358FxxBD 300 Yes − SOT-23-5,
6-Pin SNB(B)
Applications requiring a shutdown function
and a thin coil
S-8358GxxMC,
S-8358GxxBD 300 − Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage
and a thin coil
S-8358HxxMC,
S-8358HxxBD 250 Yes − SOT-23-5,
6-Pin SNB(B)
Applications requiring a shutdown function
and a thin coil
S-8358JxxMC,
S-8358JxxBD 250 − Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage
with an external resistor and a thin coil
S-8358NxxMC,
S-8358NxxBD 600 Yes − SOT-23-5,
6-Pin SNB(B)
Applications requiring a shutdown function
and a thin coil
S-8358PxxMC,
S-8358PxxBD 600 − Yes
SOT-23-5,
6-Pin SNB(B)
Applications requiring variable output voltage
with an external resistor and a thin coil
2. Package and Function List by Product Type
Table 3
Series Name Type Package Name
(Abbreviation)
Shutdown Function
Yes / No
VDD / VOUT Separate
Type
Yes / No
S-8355 Series,
S-8356 Series
K, L, M, Q (Shutdown function + VDD / VOUT
separate type)
K = 100 kHz, L = 250 kHz, M = 300 kHz,
Q = 600 kHz
MC / BD Yes Yes
MA / UA No
S-8357 Series B, H, F (Normal product)
B = 100 kHz, H = 250 kHz, F = 300 kHz MC / BD Yes No
N (Normal product)
N = 600 kHz MC / BD Yes No
E, J, G, P (VDD / VOUT separate type)
E = 100 kHz, J = 250 kHz, G = 300 kHz,
P = 600 kHz
MC / BD No Yes
MA / UA No
S-8358 Series B, H, F (Normal product)
B = 100 kHz, H = 250 kHz, F = 300 kHz MC / BD Yes No
N (Normal product)
N = 600 kHz MC/BD Yes No
E, J, G, P (VDD / VOUT separate type)
E = 100 kHz, J = 250 kHz, G = 300 kHz,
P = 600 kHz
MC / BD No Yes
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 5
3. Product Name
S-835 x x xx xx - xxx - Tx
IC direction in tape specifications *1
T2 : SOT-23-3, SOT-23-5, SOT-89-3
TF : 6-Pin SNB(B)
Product code *2
Package code
MA : SOT-23-3
MC : SOT-23-5
UA : SOT-89-3
BD : 6-Pin SNB(B)
Output voltage
15 to 65
(e.g. When the output voltage is 1.5 V, it is expressed as 15.)
Product type
B : Normal product, fOSC = 100 kHz
(S-8357/58 Series)
H : Normal product, fOSC = 250 kHz
(S-8357/58 Series)
F : Normal product, fOSC = 300 kHz
(S-8357/58 Series)
N : Normal product, fOSC = 600 kHz
(S-8357/58 Series)
E : VDD / VOUT separate type, fOSC = 100 kHz
(S-8357/58 Series)
J : VDD / VOUT separate type, fOSC = 250 kHz
(S-8357/58 Series)
G : VDD / VOUT separate type, fOSC = 300 kHz
(S-8357/58 Series)
P : VDD / VOUT separate type, fOSC = 600 kHz
(S-8357/58 Series)
K : With shutdown function + VDD / VOUT separate type, fOSC = 100 kHz
(S-8355/56 Series)
L : With shutdown function + VDD / VOUT separate type, fOSC = 250 kHz
(S-8355/56 Series)
M : With shutdown function + VDD / VOUT separate type, fOSC = 300 kHz
(S-8355/56 Series)
Q : With shutdown function + VDD / VOUT separate type, fOSC = 600 kHz
(S-8355/56 Series)
Control system
5 or 7 : PWM control
6 or 8 : PWM / PFM switching control
*1. Refer to the taping specifications.
*2. Refer to the Table 4 to Table 13 in the “4. Product Name List”.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
6
4. Product Name List
(1) S-8355 Series
Table 4
Output
voltage
S-8355KxxMC
Series
S-8355LxxMC
Series
S-8355MxxMC
Series
S-8355MxxBD
Series
1.5 V − S-8355L15MC-NCA-T2 − −
1.8 V S-8355K18MC-NAD-T2 − S-8355M18MC-MCD-T2 S-8355M18BD-MCD-TF
2.0 V S-8355K20MC-NAF-T2 S-8355L20MC-NCF-T2 S-8355M20MC-MCF-T2 −
3.1 V S-8355K31MC-NAQ-T2 − S-8355M31MC-MCQ-T2 −
3.2 V − − S-8355M32MC-MCR-T2 −
3.3 V S-8355K33MC-NAS-T2 − − −
3.4 V − − S-8355M34MC-MCT-T2 S-8355M34BD-MCT-TF
5.0 V S-8355K50MC-NBJ-T2 − S-8355M50MC-MDJ-T2 −
5.5 V − − S-8355M55MC-MDO-T2 −
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
Table 5
Output
voltage
S-8355QxxMC
Series
S-8355QxxBD
Series
1.5 V S-8355Q15MC-OWA-T2 S-8355Q15BD-OWA-TF
2.8 V − S-8355Q28BD-OWN-TF
3.1 V − S-8355Q31BD-OWQ-TF
3.4 V − S-8355Q34BD-OWT-TF
5.0 V S-8355Q50MC-OXJ-T2 S-8355Q50BD-OXJ-TF
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
(2) S-8356 Series
Output
voltage
S-8356KxxMC
Series
S-8356MxxMC
Series
S-8356MxxBD
Series
1.5 V − S-8356M15MC-MEA-T2 −
1.8 V S-8356K18MC-NED-T2 S-8356M18MC-MED-T2 S-8356M18BD-MED-TF
3.0 V − S-8356M30MC-MEP-T2 −
3.3 V S-8356K33MC-NES-T2 − −
5.0 V S-8356K50MC-NFJ-T2 S-8356M50MC-MFJ-T2 S-8356M50BD-MFJ-TF
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
Table 7
Output
voltage
S-8356QxxMC
Series
S-8356QxxBD
Series
1.8 V S-8356Q18MC-OYD-T2 −
3.3 V S-8356Q33MC-OYS-T2 −
3.7 V − S-8356Q37BD-OYW-TF
5.0 V S-8356Q50MC-OVJ-T2 S-8356Q50BD-OVJ-TF
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 7
(3) S-8357 Series
Table 8
Output
voltage
S-8357BxxMC
Series
S-8357BxxMA
Series
S-8357BxxUA
Series
S-8357ExxMC
Series
1.5 V − − − S-8357E15MC-NKA-T2
2.0 V − − − S-8357E20MC-NKF-T2
2.5 V S-8357B25MC-NIK-T2 − − −
2.6 V S-8357B26MC-NIL-T2 − − −
2.7 V S-8357B27MC-NIM-T2 − − −
2.8 V S-8357B28MC-NIN-T2 − − −
3.0 V S-8357B30MC-NIP-T2 S-8357B30MA-NIP-T2 − −
3.3 V S-8357B33MC-NIS-T2 S-8357B33MA-NIS-T2 S-8357B33UA-NIS-T2 −
3.6 V S-8357B36MC-NIV-T2 − − −
4.8 V S-8357B48MC-NJH-T2 − S-8357B48UA-NJH-T2 −
5.0 V S-8357B50MC-NJJ-T2 S-8357B50MA-NJJ-T2 S-8357B50UA-NJJ-T2 S-8357E50MC-NLJ-T2
5.2 V S-8357B52MC-NJL-T2 − − −
5.4 V S-8357B54MC-NJN-T2 − − −
6.0 V S-8357B60MC-NJT-T2 − − −
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
Table 9
Output
voltage
S-8357FxxMC
Series
S-8357GxxMC
Series
S-8357HxxMC
Series
S-8357JxxMC
Series
2.5 V − − − S-8357J25MC-NOK-T2
3.0 V − − S-8357H30MC-NMP-T2 −
3.1 V − − S-8357H31MC-NMQ-T2 −
3.2 V S-8357F32MC-MGR-T2 − − −
3.3 V S-8357F33MC-MGS-T2 − − −
3.5 V − − S-8357H35MC-NMU-T2 −
3.6 V − − S-8357H36MC-NMV-T2 −
5.0 V S-8357F50MC-MHJ-T2 S-8357G50MC-MJJ-T2 S-8357H50MC-NNJ-T2 S-8357J50MC-NPJ-T2
5.2 V S-8357F52MC-MHL-T2 − − −
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
Table 10
Output
voltage
S-8357JxxBD
Series
S-8357NxxMC
Series
3.3 V − S-8357N33MC-O2S-T2
5.0 V S-8357J50BD-NPJ-TF S-8357N50MC-O3J-T2
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
8
(4) S-8358 Series
Table 11
Output
voltage
S-8358BxxMC
Series
S-8358BxxMA
Series
S-8358BxxUA
Series
S-8358ExxMC
Series
2.0 V − − − S-8358E20MC-NSF-T2
2.3 V S-8358B23MC-NQI-T2 − − −
2.5 V S-8358B25MC-NQK-T2 − − −
2.6 V S-8358B26MC-NQL-T2 − − −
2.7 V S-8358B27MC-NQM-T2 − − −
3.0 V S-8358B30MC-NQP-T2 − − −
3.1 V S-8358B31MC-NQQ-T2 − − −
3.2 V S-8358B32MC-NQR-T2 − − −
3.3 V S-8358B33MC-NQS-T2 − S-8358B33UA-NQS-T2 −
3.5 V S-8358B35MC-NQU-T2 − − −
3.6 V S-8358B36MC-NQV-T2 − − −
3.8 V S-8358B38MC-NQX-T2 − − −
4.0 V S-8358B40MC-NQZ-T2 − − −
5.0 V S-8358B50MC-NRJ-T2 S-8358B50MA-NRJ-T2 S-8358B50UA-NRJ-T2 S-8358E50MC-NTJ-T2
6.0 V S-8358B60MC-NRT-T2 − − −
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
Table 12
Output
voltage
S-8358FxxMC
Series
S-8358GxxMC
Series
S-8358HxxMC
Series
S-8358JxxMC
Series
2.3 V − − S-8358H23MC-NUI-T2 −
2.6 V S-8358F26MC-MKL-T2 − − −
2.7 V S-8358F27MC-MKM-T2 − − −
3.0 V − − S-8358H30MC-NUP-T2 −
3.3 V S-8358F33MC-MKS-T2 − S-8358H33MC-NUS-T2 S-8358J33MC-NWS-T2
5.0 V S-8358F50MC-MLJ-T2 S-8358G50MC-MNJ-T2 S-8358H50MC-NVJ-T2 S-8358J50MC-NXJ-T2
5.3 V S-8358F53MC-MLM-T2 − − −
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
Table 13
Output
voltage
S-8358NxxMC
Series
5.3 V S-8358N53MC-O7M-T2
Remark Please contact the SII marketing department for products with an output voltage other than those specified above.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 9
Pin Configurations
Table 14 S-8357/58 Series B, H and F Types
(Without shutdown function, VDD / VOUT non-separate type)
Pin No. Symbol Pin Description
1 VOUT Output voltage pin and IC power supply pin
2 VSS GND pin
3 EXT External transistor connection pin
1
3 2
SOT-23-3
Top view
Figure 5
Table 15 S-8355/56 Series K, L, M and Q Types
(With shutdown function, VDD / VOUT separate type)
Pin No. Symbol Pin Description
1 VOUT Output voltage
2 VDD IC power supply pin
3 OFF/ON
Shutdown pin
“H”: Normal operation (Step-up operating)
“L”: Step-up stopped (Entire circuit stopped)
4 VSS GND pin
SOT-23-5
Top view
5 4
3 2 1
5 EXT External transistor connection pin
Figure 6
Table 16 S-8357/58 Series B, H, F and N Types
(With shutdown function, VDD / VOUT non-separate type)
Pin No. Symbol Pin Description
1 OFF/ON
Shutdown pin
“H”: Normal operation (Step-up operating)
“L”: Step-up stopped (Entire circuit stopped)
2 VOUT Output voltage pin and IC power supply pin
3
NC*1 No connection
4 VSS GND pin
5 EXT External transistor connection pin
*1. The NC pin indicates electrically open.
Table 17 S-8357/58 Series E, J, G and P Types
(Without shutdown function, VDD / VOUT separate type)
Pin No. Symbol Pin Description
1 VOUT Output voltage pin
2 VDD IC power supply pin
3
NC*1 No connection
4 VSS GND pin
5 EXT External transistor connection pin
*1. The NC pin indicates electrically open.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
10
Table 18 S-8357/58 Series B, H and F Types
(Without shutdown function, VDD / VOUT non-separate type)
Pin No. Symbol Pin Description
1 VSS GND pin
2 VOUT Output voltage pin and IC power supply pin
3 EXT External transistor connection pin
SOT-89-3
Top view
3
2 1
Figure 7
Table 19 S-8355/56 Series K, L, M and Q Types
(With shutdown function, VDD / VOUT separate type)
Pin No. Symbol Pin Description
1 OFF/ON
Shutdown pin
“H”: Normal operation (Step-up operating)
“L”: Step-up stopped (Entire circuit stopped)
2 VOUT Output voltage pin
3 VDD IC power supply pin
4 EXT External transistor connection pin
5
NC*1 No connection
6 VSS GND pin
*1. The NC pin indicates electrically open.
Table 20 S-8357/58 Series B, H, F and N Types
(With shutdown function, VDD / VOUT non-separate type)
Pin No. Symbol Pin Description
1 NC*1 No connection
2 OFF/ON
Shutdown pin
“H”: Normal operation (Step-up operating)
“L”: Step-up stopped (Entire circuit stopped)
3 VOUT Output voltage pin and IC power supply pin
4 EXT
External transistor connection pin
5 NC*1 No connection
6 VSS GND pin
*1. The NC pin indicates electrically open.
6-Pin SNB(B)
Top view
6
5
4
1
2
3
4
5
6
3
2
1
Bottom view
*1
*1.
Connect the heatsink of
back side at shadowed
area to the board, and set
electric potential open or
VDD.
However, do not use it as
the function of electrode.
Figure 8 Table 21 S-8357/58 Series E, J, G and P Types
(Without shutdown function, VDD / VOUT separate type)
Pin No. Symbol Pin Description
1
NC*1 No connection
2 VOUT Output voltage pin
3 VDD IC power supply pin
4 EXT External transistor connection pin
5
NC*1 No connection
6 VSS GND pin
*1. The NC pin indicates electrically open.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 11
Absolute Maximum Ratings
Table 22
(Ta = 25°C unless otherwise specified)
Item Symbol Absolute maximum rating Unit
VOUT pin voltage VOUT V
SS − 0.3 to VSS + 12 V
OFF/ON pin voltage *1 OFF/ON
V VSS − 0.3 to VSS + 12 V
VDD pin voltage *2 VDD V
SS − 0.3 to VSS + 12 V
EXT pin voltage B, H, F, N type VEXT V
SS − 0.3 to VDD + 0.3 V
Others VSS − 0.3 to VOUT + 0.3 V
EXT pin current IEXT ±80 mA
Power dissipation SOT-23-3 PD 150 mW
SOT-23-5 250 mW
SOT-89-3 500 mW
6-Pin SNB(B) 90 mW
Operating ambient temperature Topr − 40 to + 85 °C
Storage temperature Tstg − 40 to + 125 °C
*1. With shutdown function
*2. For VDD / VOUT separate type
Caution The absolute maximum ratings are rated values exceeding which the product could suffer physical
damage. These values must therefore not be exceeded under any conditions.
SOT-23-3
SOT-89-3
SOT-23-5
6-Pin SNB(B)
600
400
0
Power dissipation (P
D
) [mW]
200
050 100 150
A
mbient tem
p
erature
(
Ta
)
[
°C
]
Figure 9 Power Dissipation of The Packages (Before Mounting)
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
12
Electrical Characteristics
(1) 100 kHz Product (B, E and K Types)
Table 23 (1 / 2)
(Ta = 25°C unless otherwise specified)
Item Symbol Condition Min. Typ. Max. Unit
Measurement
circuit
Output voltage V
OUT
−
V
OUT(S)
×
0.976
V
OUT(S)
V
OUT(S)
×
1.024 V 2
Input voltage V
IN
−
−
−
10 V 2
Operation start voltage V
ST1
I
OUT
= 1 mA
−
−
0.9 V 2
Oscillation start voltage V
ST2
No external parts, Voltage applied to V
OUT
−
−
0.8 V 1
Operation holding voltage V
HLD
I
OUT
= 1 mA, Judged by decreasing V
IN
voltage gradually 0.7
−
−
V 2
Current consumption 1 I
SS1
V
OUT
= V
OUT(S)
×
0.95 S-835xx15 to 19
−
14.0 23.4
µ
A 1
S-835xx20 to 29
−
19.7 32.9
µ
A 1
S-835xx30 to 39
−
25.9 43.2
µ
A 1
S-835xx40 to 49
−
32.6 54.4
µ
A 1
S-835xx50 to 59
−
39.8 66.4
µ
A 1
S-835xx60 to 65
−
47.3 78.9
µ
A 1
Current consumption 2 I
SS2
V
OUT
= V
OUT(S)
+
0.5 V S-835xx15 to 19
−
5.6 11.1
µ
A 1
S-835xx20 to 29
−
5.8 11.5
µ
A 1
S-835xx30 to 39
−
5.9 11.8
µ
A 1
S-835xx40 to 49
−
6.1 12.1
µ
A 1
S-835xx50 to 59
−
6.3 12.5
µ
A 1
S-835xx60 to 65
−
6.4 12.8
µ
A 1
Current consumption during
shutdown
(With shutdown function)
I
SSS
OFF/ON
V
= 0 V
−
−
0.5
µ
A 1
EXT pin output current I
EXTH
V
EXT
= V
OUT
−
0.4 V S-835xx15 to 19
−
4.5
−
8.9
−
mA 1
S-835xx20 to 24
−
6.2
−
12.3
−
mA 1
S-835xx25 to 29
−
7.8
−
15.7
−
mA 1
S-835xx30 to 39
−
10.3
−
20.7
−
mA 1
S-835xx40 to 49
−
13.3
−
26.7
−
mA 1
S-835xx50 to 59
−
16.1
−
32.3
−
mA 1
S-835xx60 to 65
−
18.9
−
37.7
−
mA 1
I
EXTL
V
EXT
= 0.4 V S-835xx15 to 19 9.5 19.0
−
mA 1
S-835xx20 to 24 12.6 25.2
−
mA 1
S-835xx25 to 29 15.5 31.0
−
mA 1
S-835xx30 to 39 19.2 38.5
−
mA 1
S-835xx40 to 49 23.8 47.6
−
mA 1
S-835xx50 to 59 27.4 54.8
−
mA 1
S-835xx60 to 65 30.3 60.6
−
mA 1
Line regulation
∆
V
OUT1
V
IN
= V
OUT(S)
×
0.4 to
×
0.6
−
30 60 mV 2
Load regulation
∆
V
OUT2
I
OUT
= 10
µ
A to V
OUT(S)
/ 50
×
1.25
−
30 60 mV 2
Output voltage temperature
coefficient
OUT
OUT
VTa∆
V∆
•
Ta =
−
40 to
+
85
°
C
−
±
50
−
ppm /
°
C2
Oscillation frequency f
OSC
V
OUT
= V
OUT(S)
×
0.95 85 100 115 kHz 1
Maximum duty ratio MaxDuty V
OUT
= V
OUT(S)
×
0.95 75 83 90 % 1
PWM / PFM switching duty
ratio (For S-8356/58 Series) PFMDuty V
IN
= V
OUT(S)
−
0.1 V, No-load 10 15 24 % 1
V
SH
Measured oscillation at EXT pin 0.75
−
−
V 1
V
SL1
At V
OUT
≥
1.5 V
−
−
0.3 V 1
OFF/ON
pin input voltage
(With shutdown function) V
SL2
Judged oscillation stop at
EXT pin At V
OUT
<
1.5 V
−
−
0.2 V 1
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 13
Table 23 (2 / 2)
(Ta = 25°C unless otherwise specified)
Item Symbol Condition Min. Typ. Max. Unit
Measurement
circuit
I
SH
OFF/ON
V
= V
OUT(S)
×
0.95
−
0.1
−
0.1
µ
A 1
OFF/ON
pin input current
(For with shutdown function) I
SL
OFF/ON
V
= 0 V
−
0.1
−
0.1
µ
A 1
Soft start time t
SS
−
3.0 6.0 12.0 ms 2
Efficiency EFFI
−
−
85
−
% 2
External parts
Coil: CDRH6D28-470 of Sumida Corporation
Diode: RB461F (Schottky type) of Rohm Co., Ltd.
Capacitor: F93 (16 V, 47 µF tantalum type) of Nichicon Corporation
Transistor: CPH3210 of Sanyo Electric Co., Ltd.
Base resistor (Rb): 1.0 kΩ
Base capacitor (Cb): 2200 pF (ceramic type)
VIN = VOUT(S) × 0.6 applied, IOUT = VOUT(S) / 50 Ω
With shutdown function : OFF/ON pin is connected to VOUT
For VDD / VOUT separate type : VDD pin is connected to VOUT pin
Remark 1. VOUT(S) specified above is the set output voltage value, and VOUT is the typical value of the actual output voltage.
2. VDD / VOUT separate type
A step-up operation is performed from VDD = 0.8 V. However, 1.8 V ≤ VDD ≤ 10 V is recommended stabilizing
the output voltage and oscillation frequency. (VDD ≥ 1.8 V must be applied for products with a set value of
less than 1.9 V.)
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
14
(2) 250 kHz Product (H, J and L Types)
Table 24
(Ta = 25°C unless otherwise specified)
Item Symbol Condition Min. Typ. Max. Unit
Measurement
circuit
Output voltage V
OUT
−
V
OUT(S)
×
0.976
V
OUT(S)
V
OUT(S)
×
1.024 V 2
Input voltage V
IN
−
−
−
10 V 2
Operation start voltage V
ST1
I
OUT
= 1 mA
−
−
0.9 V 2
Oscillation start voltage V
ST2
No external parts, Voltage applied to V
OUT
−
−
0.8 V 1
Operation holding voltage V
HLD
I
OUT
= 1 mA, Judged by decreasing V
IN
voltage gradually 0.7
−
−
V 2
Current consumption 1 I
SS1
V
OUT
= V
OUT(S)
×
0.95 S-835xx15 to 19
−
28.9 48.2
µ
A 1
S-835xx20 to 29
−
42.7 71.1
µ
A 1
S-835xx30 to 39
−
58.0 96.7
µ
A 1
S-835xx40 to 49
−
74.5 124.1
µ
A 1
S-835xx50 to 59
−
92.0 153.4
µ
A 1
S-835xx60 to 65
−
110.5 184.2
µ
A 1
Current consumption 2 I
SS2
V
OUT
= V
OUT(S)
+
0.5 V S-835xx15 to 19
−
8.7 17.3
µ
A 1
S-835xx20 to 29
−
8.8 17.6
µ
A 1
S-835xx30 to 39
−
9.0 18.0
µ
A 1
S-835xx40 to 49
−
9.2 18.3
µ
A 1
S-835xx50 to 59
−
9.3 18.6
µ
A 1
S-835xx60 to 65
−
9.5 19.0
µ
A 1
Current consumption during
shutdown
(With shutdown function)
I
SSS
OFF/ON
V
= 0 V
−
−
0.5
µ
A 1
EXT pin output current I
EXTH
V
EXT
= V
OUT
−
0.4 V S-835xx15 to 19
−
4.5
−
8.9
−
mA 1
S-835xx20 to 24
−
6.2
−
12.3
−
mA 1
S-835xx25 to 29
−
7.8
−
15.7
−
mA 1
S-835xx30 to 39
−
10.3
−
20.7
−
mA 1
S-835xx40 to 49
−
13.3
−
26.7
−
mA 1
S-835xx50 to 59
−
16.1
−
32.3
−
mA 1
S-835xx60 to 65
−
18.9
−
37.7
−
mA 1
I
EXTL
V
EXT
= 0.4 V S-835xx15 to 19 9.5 19.0
−
mA 1
S-835xx20 to 24 12.6 25.2
−
mA 1
S-835xx25 to 29 15.5 31.0
−
mA 1
S-835xx30 to 39 19.2 38.5
−
mA 1
S-835xx40 to 49 23.8 47.6
−
mA 1
S-835xx50 to 59 27.4 54.8
−
mA 1
S-835xx60 to 65 30.3 60.6
−
mA 1
Line regulation
∆
V
OUT1
V
IN
= V
OUT(S)
×
0.4 to
×
0.6
−
30 60 mV 2
Load regulation
∆
V
OUT2
I
OUT
= 10
µ
A to V
OUT(S)
/ 50
×
1.25
−
30 60 mV 2
Output voltage temperature
coefficient
OUT
OUT
VTa∆
V∆
•
Ta =
−
40 to
+
85
°
C
−
±
50
−
ppm /
°
C2
Oscillation frequency f
OSC
V
OUT
= V
OUT(S)
×
0.95 212.5 250 287.5 kHz 1
Maximum duty ratio MaxDuty V
OUT
= V
OUT(S)
×
0.95 70 78 85 % 1
PWM / PFM switching duty
ratio (For S-8356/58 Series) PFMDuty V
IN
= V
OUT(S)
−
0.1 V, No-load 10 15 24 % 1
V
SH
Measured oscillation at EXT pin 0.75
−
−
V 1
V
SL1
At V
OUT
≥
1.5 V
−
−
0.3 V 1
OFF/ON
pin input voltage
(With shutdown function) V
SL2
Judged oscillation stop at
EXT pin At V
OUT
<
1.5 V
−
−
0.2 V 1
I
SH
OFF/ON
V
= V
OUT(S)
×
0.95
−
0.1
−
0.1
µ
A 1
OFF/ON
pin input current
(With shutdown function) I
SL
OFF/ON
V
= 0 V
−
0.1
−
0.1
µ
A 1
Soft start time t
SS
−
1.5 3.0 6.0 ms 2
Efficiency EFFI
−
−
85
−
% 2
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 15
External parts
Coil: CDRH6D28-220 of Sumida Corporation
Diode: RB461F (Schottky type) of Rohm Co., Ltd.
Capacitor: F93 (16 V, 47 µF tantalum type) of Nichicon Corporation
Transistor: CPH3210 of Sanyo Electric Co., Ltd.
Base resistor (Rb): 1.0 kΩ
Base capacitor (Cb): 2200 pF (ceramic type)
VIN = VOUT(S) × 0.6 applied, IOUT = VOUT(S) / 50 Ω
With shutdown function : OFF/ON pin is connected to VOUT
For VDD / VOUT separate type : VDD pin is connected to VOUT pin
Remark 1. VOUT(S) specified above is the set output voltage value, and VOUT is the typical value of the actual output voltage.
2. VDD / VOUT separate type
A step-up operation is performed from VDD = 0.8 V. However, 1.8 V ≤ VDD ≤ 10 V is recommended stabilizing
the output voltage and oscillation frequency. (VDD ≥ 1.8 V must be applied for products with a set value of
less than 1.9 V.)
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
16
(3) 300 kHz Product (F, G and M Types)
Table 25
(Ta = 25°C unless otherwise specified)
Item Symbol Condition Min. Typ. Max. Unit
Measurement
circuit
Output voltage V
OUT
−
V
OUT(S)
×
0.976
V
OUT(S)
V
OUT(S)
×
1.024 V 2
Input voltage V
IN
−
−
−
10 V 2
Operation start voltage V
ST1
I
OUT
= 1 mA
−
−
0.9 V 2
Oscillation start voltage V
ST2
No external parts, Voltage applied to V
OUT
−
−
0.8 V 1
Operation holding voltage V
HLD
I
OUT
= 1 mA, Judged by decreasing V
IN
voltage gradually 0.7
−
−
V 2
Current consumption 1 I
SS1
V
OUT
= V
OUT(S)
×
0.95 S-835xx15 to 19
−
33.8 56.4
µ
A 1
S-835xx20 to 29
−
50.3 83.9
µ
A 1
S-835xx30 to 39
−
68.6 114.4
µ
A 1
S-835xx40 to 49
−
88.4 147.4
µ
A 1
S-835xx50 to 59
−
109.4 182.4
µ
A 1
S-835xx60 to 65
−
131.6 219.3
µ
A 1
Current consumption 2 I
SS2
V
OUT
= V
OUT(S)
+
0.5 V S-835xx15 to 19
−
9.7 19.4
µ
A 1
S-835xx20 to 29
−
9.9 19.7
µ
A 1
S-835xx30 to 39
−
10.0 20.0
µ
A 1
S-835xx40 to 49
−
10.2 20.4
µ
A 1
S-835xx50 to 59
−
10.4 20.7
µ
A 1
S-835xx60 to 65
−
10.5 21.0
µ
A 1
Current consumption during
shutdown
(With shutdown function)
I
SSS
OFF/ON
V
= 0 V
−
−
0.5
µ
A 1
EXT pin output current I
EXTH
V
EXT
= V
OUT
−
0.4 V S-835xx15 to 19
−
4.5
−
8.9
−
mA 1
S-835xx20 to 24
−
6.2
−
12.3
−
mA 1
S-835xx25 to 29
−
7.8
−
15.7
−
mA 1
S-835xx30 to 39
−
10.3
−
20.7
−
mA 1
S-835xx40 to 49
−
13.3
−
26.7
−
mA 1
S-835xx50 to 59
−
16.1
−
32.3
−
mA 1
S-835xx60 to 65
−
18.9
−
37.7
−
mA 1
I
EXTL
V
EXT
= 0.4 V S-835xx15 to 19 9.5 19.0
−
mA 1
S-835xx20 to 24 12.6 25.2
−
mA 1
S-835xx25 to 29 15.5 31.0
−
mA 1
S-835xx30 to 39 19.2 38.5
−
mA 1
S-835xx40 to 49 23.8 47.6
−
mA 1
S-835xx50 to 59 27.4 54.8
−
mA 1
S-835xx60 to 65 30.3 60.6
−
mA 1
Line regulation
∆
V
OUT1
V
IN
= V
OUT(S)
×
0.4 to
×
0.6
−
30 60 mV 2
Load regulation
∆
V
OUT2
I
OUT
= 10
µ
A to V
OUT(S)
/ 50
×
1.25
−
30 60 mV 2
Output voltage temperature
coefficient
OUT
OUT
VTa∆
V∆
•
Ta =
−
40 to
+
85
°
C
−
±
50
−
ppm /
°
C2
Oscillation frequency f
OSC
V
OUT
= V
OUT(S)
×
0.95 255 300 345 kHz 1
Maximum duty ratio MaxDuty V
OUT
= V
OUT(S)
×
0.95 70 78 85 % 1
PWM / PFM switching duty
ratio (For S-8356/58 Series) PFMDuty V
IN
= V
OUT(S)
−
0.1 V, No-load 10 15 24 % 1
V
SH
Measured oscillation at EXT pin 0.75
−
−
V 1
V
SL1
At V
OUT
≥
1.5 V
−
−
0.3 V 1
OFF/ON
pin input voltage
(With shutdown function) V
SL2
Judged oscillation stop at
EXT pin At V
OUT
<
1.5 V
−
−
0.2 V 1
I
SH
OFF/ON
V
= V
OUT(S)
×
0.95
−
0.1
−
0.1
µ
A 1
OFF/ON
pin input current
(With shutdown function) I
SL
OFF/ON
V
= 0 V
−
0.1
−
0.1
µ
A 1
Soft start time t
SS
−
1.5 3.0 6.0 ms 2
Efficiency EFFI
−
−
85
−
% 2
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 17
External parts
Coil: CDRH6D28-220 of Sumida Corporation
Diode: RB461F (Schottky type) of Rohm Co., Ltd.
Capacitor: F93 (16 V, 47 µF tantalum type) of Nichicon Corporation
Transistor: CPH3210 of Sanyo Electric Co., Ltd.
Base resistor (Rb): 1.0 kΩ
Base capacitor (Cb): 2200 pF (ceramic type)
VIN = VOUT(S) × 0.6 applied, IOUT = VOUT(S) / 50 Ω
With shutdown function : OFF/ON pin is connected to VOUT
For VDD / VOUT separate type : VDD pin is connected to VOUT pin
Remark 1. VOUT(S) specified above is the set output voltage value, and VOUT is the typical value of the actual output voltage.
2. VDD / VOUT separate type
A step-up operation is performed from VDD = 0.8 V. However, 1.8 V ≤ VDD ≤ 10 V is recommended stabilizing
the output voltage and oscillation frequency. (VDD ≥ 1.8 V must be applied for products with a set value of
less than 1.9 V.)
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
18
(4) 600 kHz Product (N Type)
Table 26
(Ta = 25°C unless otherwise specified)
Item Symbol Condition Min. Typ. Max. Unit
Measurement
circuit
Output voltage V
OUT
−
V
OUT(S)
×
0.976
V
OUT(S)
V
OUT(S)
×
1.024 V 2
Input voltage V
IN
−
−
−
10 V 2
Operation start voltage V
ST1
I
OUT
= 1 mA
−
−
0.9 V 2
Oscillation start voltage V
ST2
No external parts, Voltage applied to V
OUT
−
−
0.8 V 1
Operation holding voltage V
HLD
I
OUT
= 1 mA, Judged by decreasing V
IN
voltage gradually 0.7
−
−
V 2
Current consumption 1 I
SS1
V
OUT
= V
OUT(S)
×
0.95 S-835xx15 to 19
−
63.6 105.9
µ
A 1
S-835xx20 to 29
−
96.4 160.6
µ
A 1
S-835xx30 to 39
−
132.8 221.3
µ
A 1
S-835xx40 to 49
−
172.2 286.9
µ
A 1
S-835xx50 to 59
−
214.0 356.7
µ
A 1
S-835xx60 to 65
−
240.2 400.3
µ
A 1
Current consumption 2 I
SS2
V
OUT
= V
OUT(S)
+
0.5 V S-835xx15 to 19
−
15.9 31.8
µ
A 1
S-835xx20 to 29
−
16.1 32.1
µ
A 1
S-835xx30 to 39
−
16.2 32.4
µ
A 1
S-835xx40 to 49
−
16.4 32.8
µ
A 1
S-835xx50 to 59
−
16.6 33.1
µ
A 1
S-835xx60 to 65
−
16.7 33.3
µ
A 1
Current consumption during
shutdown I
SSS
OFF/ON
V
= 0 V
−
−
0.5
µ
A 1
EXT pin output current I
EXTH
V
EXT
= V
OUT
−
0.4 V S-835xx15 to 19
−
4.5
−
8.9
−
mA 1
S-835xx20 to 24
−
6.2
−
12.3
−
mA 1
S-835xx25 to 29
−
7.8
−
15.7
−
mA 1
S-835xx30 to 39
−
10.3
−
20.7
−
mA 1
S-835xx40 to 49
−
13.3
−
26.7
−
mA 1
S-835xx50 to 59
−
16.1
−
32.3
−
mA 1
S-835xx60 to 65
−
18.9
−
37.7
−
mA 1
I
EXTL
V
EXT
= 0.4 V S-835xx15 to 19 9.5 19.0
−
mA 1
S-835xx20 to 24 12.6 25.2
−
mA 1
S-835xx25 to 29 15.5 31.0
−
mA 1
S-835xx30 to 39 19.2 38.5
−
mA 1
S-835xx40 to 49 23.8 47.6
−
mA 1
S-835xx50 to 59 27.4 54.8
−
mA 1
S-835xx60 to 65 30.3 60.6
−
mA 1
Line regulation
∆
V
OUT1
V
IN
= V
OUT(S)
×
0.4 to
×
0.6
−
30 60 mV 2
Load regulation
∆
V
OUT2
I
OUT
= 10
µ
A to V
OUT(S)
/ 50
×
1.25
−
30 60 mV 2
Output voltage temperature
coefficient
OUT
OUT
VTa∆
V∆
•
Ta =
−
40 to
+
85
°
C
−
±
50
−
ppm /
°
C2
Oscillation frequency f
OSC
V
OUT
= V
OUT(S)
×
0.95 510 600 690 kHz 1
Maximum duty ratio MaxDuty V
OUT
= V
OUT(S)
×
0.95 65 78 85 % 1
PWM / PFM switching duty
ratio (For S-8356/58 Series) PFMDuty V
IN
= V
OUT(S)
−
0.1 V, No-load 10 15 24 % 1
OFF/ON
pin input voltage V
SH
Measured oscillation at EXT pin 0.75
−
−
V 1
V
SL1
At V
OUT
≥
1.5 V
−
−
0.3 V 1
V
SL2
Judged oscillation stop at
EXT pin At V
OUT
<
1.5 V
−
−
0.2 V 1
OFF/ON
pin input current I
SH
OFF/ON
V
= V
OUT(S)
×
0.95
−
0.1
−
0.1
µ
A 1
I
SL
OFF/ON
V
= 0 V
−
0.1
−
0.1
µ
A 1
Soft start time t
SS
−
1.5 3.0 6.0 ms 2
Efficiency EFFI
−
−
85
−
% 2
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
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External parts
Coil: CDRH6D28-100 of Sumida Corporation
Diode: RB461F (Schottky type) of Rohm Co., Ltd.
Capacitor: F93 (16 V, 47 µF tantalum type) of Nichicon Corporation
Transistor: CPH3210 of Sanyo Electric Co., Ltd.
Base resistor (Rb): 1.0 kΩ
Base capacitor (Cb): 2200 pF (ceramic type)
VIN = VOUT(S) × 0.6 applied, IOUT = VOUT(S) / 50 Ω, OFF/ON = VOUT
Remark VOUT(S) specified above is the set output voltage value, and VOUT is the typical value of the actual output voltage.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
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20
(5) 600 kHz Product (P and Q types)
Table 27
(Ta = 25°C unless otherwise specified)
Item Symbol Condition Min. Typ. Max. Unit
Measurement
circuit
Output voltage V
OUT
−
V
OUT(S)
×
0.976
V
OUT(S)
V
OUT(S)
×
1.024 V 4
Input voltage V
IN
−
−
−
10 V 4
Operation start voltage V
ST1
I
OUT
= 1 mA
−
−
0.9 V 4
Oscillation start voltage V
ST2
No external parts, Voltage applied to V
DD
−
−
0.8 V 3
Operation holding voltage V
HLD
I
OUT
= 1 mA, Judged by decreasing V
IN
voltage gradually 0.7
−
−
V 4
Current consumption 1 I
SS1
V
DD
= 3.3 V
−
132.8 221.3
µ
A 3
Current consumption 2 I
SS2
V
DD
= 3.3 V
−
16.2 32.4
µ
A 3
Current consumption during
shutdown
(With shutdown function)
I
SSS
OFF/ON
V
= 0 V
−
−
0.5
µ
A 3
EXT pin output current I
EXTH
V
DD
= 3.3 V
−
10.3
−
20.7
−
mA 3
I
EXTL
V
DD
= 3.3 V 19.2 38.5
−
mA 3
Line regulation
∆
V
OUT1
V
IN
= V
OUT(S)
×
0.4 to
×
0.6
−
30 60 mV 4
Load regulation
∆
V
OUT2
I
OUT
= 10
µ
A to V
OUT(S)
/ 50
×
1.25
−
30 60 mV 4
Output voltage temperature
coefficient
OUT
OUT
VTa
V
•∆
∆
Ta =
−
40 to
+
85
°
C
−
±
50
−
ppm /
°
C4
Oscillation frequency f
OSC
V
DD
= 3.3 V 510 600 690 kHz 3
Maximum duty ratio MaxDuty V
DD
= 3.3 V 65 78 85 % 3
PWM / PFM switching duty
ratio (For S-8356/58 Series) PFMDuty V
IN
= V
OUT(S)
−
0.1 V, No-load 10 15 24 % 3
V
SH
Measured oscillation at EXT pin 0.75
−
−
V 3
V
SL1
At V
OUT
≥
1.5 V
−
−
0.3 V 3
OFF/ON
pin input voltage
(With shutdown function) V
SL2
Judged oscillation stop at
EXT pin At V
OUT
<
1.5 V
−
−
0.2 V 3
I
SH
OFF/ON
V
= V
OUT(S)
×
0.95
−
0.1
−
0.1
µ
A 3
OFF/ON
pin input current
(With shutdown function) I
SL
OFF/ON
V
= 0 V
−
0.1
−
0.1
µ
A 3
Soft start time t
SS
−
1.5 3.0 6.0 ms 4
Efficiency EFFI
−
−
85
−
% 4
External parts
Coil: CDRH6D28-100 of Sumida Corporation
Diode: RB461F (Schottky type) of Rohm Co., Ltd.
Capacitor: F93 (16 V, 47 µF tantalum type) of Nichicon Corporation
Transistor: CPH3210 of Sanyo Electric Co., Ltd.
Base resistor (Rb): 1.0 kΩ
Base capacitor (Cb): 2200 pF (ceramic type)
VIN = VOUT(S) × 0.6 applied, IOUT = VOUT(S) / 50 Ω, OFF/ON = VOUT
Remark 1. VOUT(S) specified above is the set output voltage value, and VOUT is the typical value of the actual output voltage.
2. VDD / VOUT separate type
A step-up operation is performed from VDD = 0.8 V. However, 1.8 V ≤ VDD ≤ 10 V is recommended stabilizing
the output voltage and oscillation frequency. (VDD ≥ 1.8 V must be applied for products with a set value of
less than 1.9 V.)
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
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Measurement Circuits
1.
Oscilloscope
A
+
−
VSS
EXT
VOUT
VDD
*2
0.1 µF
OFF/ON
*1
Figure 10
2.
V
CD
Rb
VSS
EXT VOUT
VDD*2
0.1 µF
OFF/ON
*1
+
−
+
−
Figure 11
3.
Oscilloscope
VSS
EXT
VOUT
VDD
0.1 µF
A
OFF/ON
*1
+
−
Figure 12
4.
V
C
D
R
b
VSS
EXT VOUT
VDD
0.1 µF
OFF/ON
*1
+
−
+
−
Figure 13
*1. With shutdown function
*2. For VDD / VOUT separate type
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S-8355/56/57/58 Series Rev.4.2_01
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Operation
1. Switching Control Types
1.1 PWM Control (S-8355/57 Series)
The S-8355/57 Series is a DC-DC converter using a pulse width modulation method (PWM) and features a low
current consumption.
In conventional PFM DC-DC converters, pulses are skipped when the output load current is low, causing a
fluctuation in the ripple frequency of the output voltage, resulting in an increase in the ripple voltage.
The switching frequency does not change, although the pulse width changes from 0 to 83% (78% for F, G, H, J, L,
M, N, P and Q types) corresponding to each load current. The ripple voltage generated from switching can thus
be removed easily through a filter because the switching frequency is constant.
1.2 PWM/PFM Switching Control (S-8356/58 Series)
S-8356/58 Series is a DC-DC converter that automatically switches between a pulse width modulation method
(PWM) and a pulse frequency modulation method (PFM), depending on the load current, and features low current
consumption.
The S-8356/58 Series operates under PWM control with the pulse width duty changing from 15 to 83% (78% for
F, G, H, J, L, M, N, P and Q types) in a high output load current area.
The S-8356/58 Series operates under PFM control with the pulse width duty fixed at 15%, and pulses are skipped
according to the load current. The oscillation circuit thus oscillates intermittently so that the resultant lower self
current consumption prevents a reduction in the efficiency at a low load current. The switching point from PWM
control to PFM control depends on the external devices (coil, diode, etc.), input voltage and output voltage. This
series are an especially highly efficient DC-DC converter at an output current around 100 µA.
2. Soft Start Function
For this IC, the built-in soft start circuit controls the rush current and overshoot of the output voltage when
powering on or when the OFF/ON pin is switched to the “H” level.
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3. OFFON/ Pin (Shutdown Pin) (SOT-23-5 Package Products of S-8355/56/57/58 Series B, H, F, K, L, M, N and Q
Types, and 6-Pin SNB(B) Package Products)
OFF/ON pin stops or starts step-up operation.
Setting the OFF/ON pin to the “L” level stops operation of all the internal circuits and reduces the current
consumption significantly.
DO NOT use the OFF/ON pin in a floating state because it has the structure shown in Figure 14 and is not pulled
up or pulled down internally. DO NOT apply a voltage of between 0.3 V and 0.75 V to the OFF/ON pin because
applying such a voltage increases the current consumption. If the OFF/ON pin is not used, connect it to the VOUT
pin.
The OFF/ON pin does not have hysteresis.
Table 28
OFF/ON pin CR oscillation circuit Output voltage
“H” Operation Fixed
“L” Stop
≅VIN*1
*1. Voltage obtained by subtracting the voltage drop due to the DC resistance of the inductor and the diode forward
voltage from VIN.
VSS
VOUT
*1
OFF/ON
*1. VDD for K, L, M and Q types.
Figure 14 OFFON/ Pin Structure
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4. Operation
The following are the basic equations [(1) through (7)] of the step-up switching regulator. (Refer to Figure 15.)
C
L
M1
D
VOUT
CONT
VIN
L
+
EXT
VSS
−
Figure 15 Step-Up Switching Regulator Circuit for Basic Equation
Voltage at CONT pin at the moment M1 is turned ON (VA) *1 :
VA = VS *2 (1)
*1. Current flowing through L (IL) is zero.
*2. Non-saturated voltage of M1.
The change in IL over time :
L
VV
L
V
dt
dI SINLL −
== (2)
Integration of equation (2) (IL) :
t
L
VV
ISIN
L•
−
= (3)
IL flows while M1 is ON (tON). The time of tON is determined by the oscillation frequency of OSC.
The peak current (IPK) after tON :
ON
SIN
PK t
L
VV
I•
−
= (4)
The energy stored in L is represented by 1/2 • L (IPK)2.
When M1 is turned OFF (tOFF), the energy stored in L is emitted through a diode to the output capacitor.
Then, the reverse voltage (VL) is generated :
VL = (VOUT + VD*1) − VIN (5)
*1. Diode forward voltage
The voltage at CONT pin rises only by VOUT+VD.
The change in the current (IL) flowing through the diode into VOUT during tOFF :
L
VVV
L
V
dt
dI INDOUTLL −+
== (6)
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Integration of the equation (6) is as follows :
t
L
VVV
II INDOUT
PKL •
−+
−= (7)
During tON, the energy is stored in L and is not transmitted to VOUT. When receiving the output current (IOUT) from VOUT,
the energy of the capacitor (CL) is consumed. As a result, the pin voltage of CL is reduced, and goes to the lowest level
after M1 is turned ON (tON). When M1 is turned OFF, the energy stored in L is transmitted through the diode to CL, and
the voltage of CL rises rapidly. VOUT is a time function, and therefore indicates the maximum value (ripple voltage (VP−P) )
when the current flowing through into VOUT and load current (IOUT) match.
Next, the ripple voltage is determined as follows.
IOUT vs. t1 (time) from when M1 is turned OFF (after tON) to when VOUT reaches the maximum level :
1
INDOUT
PKOUT t
L
VVV
II •
−+
−= (8)
−+
•−=∴
INDOUT
OUTPK1 VVV
L
)II(t (9)
When M1 is turned OFF (tOFF), IL = 0 (when the energy of the inductor is completely transmitted). Based on equation (7) :
PK
OFF
INDOUT I
t
VVV
L=
−+ (10)
When substituting equation (10) for equation (9) :
OFF
PK
OUT
OFF1 t
I
I
tt •
−= (11)
Electric charge ∆Q1 which is charged in CL during t1 :
2
1
INDOUT
1PK
1t
0
INDOUT
1t
0
PKL
1t
0
1t
2
1
L
VVV
tItdt
L
VVV
dtIdtIQ •
−+
−•=•
−+
−•==∆ ∫∫∫ (12)
When substituting equation (12) for equation (9) :
()
1
OUTPK
1OUTPKPK t
2
II
tII
2
1
I1Q •
+
=•−−=∆ (13)
A rise in voltage (VP−P) due to ∆Q 1 :
1
OUTPK
LL
1
PP t
2
II
C
1
C
Q∆
V•
+
•==
− (14)
When taking into consideration IOUT to be consumed during t1 and the Equivalent Series Resistance (RESR) of CL :
L
1OUT
ESR
OUTPKOUTPK
LL
1
PP C
tI
R
2
II
1t
2
II
C
1
C
Q
V•
−•
+
+•
+
•=
∆
=
− (15)
When substituting equation (11) for equation (15) :
ESR
OUTPK
L
OFF
PK
2
OUTPK
PP R
2
II
C
t
I2
)II(
V•
+
+•
−
=
− (16)
Therefore to reduce the ripple voltage, it is important that the capacitor connected to the output pin has a large capacity
and a small RESR.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
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External Parts Selection
The relationship between the major characteristics of the step-up circuit and the characteristics parameters of the
external parts are shown in Figure 16.
For higher efficiency ?
For larger output current ? Operation
efficiency
Stand-by
efficiency
For smaller ripple voltage ?
Smaller inductance
Larger inductance
Smaller direct current resistance of inductor
Larger output capacitance
Larger output capacitance
With MOS FET,
smaller ON resistance
With MOS FET,
smaller input capacitance
With bipolar transistor,
smaller external resistance R
b
With bipolar transistor, larger
external resistance R
b
Figure 16 Relationship between Major Characteristics of Step-up Circuit and External Parts
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
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1. Inductor
The inductance value (L value) has a strong influence on the maximum output current (IOUT) and efficiency (η).
Figure 17 shows the relationship between the IOUT and η dependency on L of S-8355/56/57/58.
F, G, H, J, L and M types
CDRH6D28, V
OUT
= 5.0 V, V
IN
= 3.0 V
Recommended range
I
OUT
η
4.7 47
L value (µH)
Efficiency
decreases
I
OUT
decreases
I
PK
increases
Coil size :
smaller
Efficiency
decreases
I
OUT
decreases
I
PK
decreases
Coil size : bigger
Figure 17 L Value vs. IOUT Characteristics, L Value vs. η Characteristics
The peak current (IPK) increases by decreasing L value and the stability of the circuit improves and IOUT increases. If L
value is decreased, the efficiency falls causing a decline in the current drive capacity for the switching transistor, and
IOUT decreases.
The loss of IPK by the switching transistor decreases by increasing L value and the efficiency becomes maximum at a
certain L value. Further increasing L value decreases the efficiency due to the loss of the direct current resistance of
the coil. IOUT also decreases.
A higher oscillation frequency allows selection of a lower L value, making the coil smaller.
The recommended inductances are a 22 to 100 µH for B, E, and K types, a 4.7 to 47 µH for F, G, H, J, L, and M
types, 3.0 to 22 µH for N, P and Q types.
Be careful of the allowable inductor current when choosing an inductor. Exceeding the allowable current of the
inductor causes magnetic saturation, much lower efficiency and destruction of the IC chip due to a large current.
Choose an inductor so that IPK does not exceed the allowable current. IPK in discontinuous mode is calculated by the
following equation:
Lf
)VVV(I 2
I
OSC
INDOUT
OUT
PK •
−+
= (A) (17)
fosc = oscillation frequency, VD ≅ 0.4 V.
2. Diode
Use an external diode that meets the following requirements :
• Low forward voltage : VF < 0.3 V
• High switching speed : 500 ns max.
• Reverse voltage : VOUT + VF or more
• Current rate : IPK or more
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3. Capacitor (CIN, CL)
A capacitor on the input side (CIN) improves the efficiency by reducing the power impedance and stabilizing the input
current. Select a CIN value according to the impedance of the power supply used.
A capacitor on the output side (CL) is used for smoothing the output voltage. For step-up types, the output voltage
flows intermittently to the load current, so step-up types need a larger capacitance than step-down types. Therefore,
select an appropriate capacitor in accordance with the ripple voltage, which increases in case of a higher output
voltage or a higher load current. The capacitor value should be 10 µF or more.
Select an appropriate capacitor the equivalent series resistance (RESR) for stable output voltage. The stable voltage
range in this IC depends on the RESR. Although the inductance value (L value) is also a factor, an RESR of 30 to 500
mΩ maximizes the characteristics. However, the best RESR value may depend on the L value, the capacitance, the
wiring, and the applications (output load). Therefore, fully evaluate the RESR under the actual operating conditions to
determine the best value.
Refer to the “3. Example of Ceramic Capacitor Application” (Figure 27) in the “ Application Circuit” for the
circuit example using a ceramic capacitor and the external resistance of the capacitor (RESR).
4. External Transistor
An enhancement (N-channel) MOS FET type or A bipolar (NPN) type can be used as the external transistor.
4.1 Enhancement (N-channel) MOS FET Type
Figure 18 is a circuit example using a MOS FET transistor (N-channel).
V
OUT
EXT
VOUT
+
−
OFF/ON
*2
VSS
VDD
*1
+
−
*1. For VDD / VOUT separate type.
*2. With shutdown function.
Figure 18 Circuit Example Using MOS FET (N-channel) Type
An N-channel power MOS FET should be used for the MOS FET. Because the gate voltage and current of the
external power MOS FET are supplied from the stepped-up output voltage (VOUT), the MOS FET is driven more
effectively.
A large current may flow during startup, depending on the MOS FET selection. So perform sufficient evaluation
using the actual devices. Also recommend to use a MOS FET with an input capacitance of 700 pF or less.
Since the ON-resistance of the MOS FET might depend on the difference between the output voltage (VOUT) and
the threshold voltage of the MOS FET, and affect the output current as well as the efficiency, the threshold
voltage should be low. When the output voltage is low, the circuit operates only when the MOS FET has a
threshold voltage lower than the output voltage.
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4.2 Bipolar (NPN) Type
A circuit example using the CPH3210 (hFE = 200 to 560) from Sanyo Electric Co., Ltd. As a bipolar transistor
(NPN) is shown in Figure 20 to 25 in the “ Standard Circuits”. The hFE value and Rb value of the bipolar
transistor determine the driving capacity to increase the output current using a bipolar transistor. A peripheral
circuit example of the transistor is shown in Figure 19.
Nch
Pch
VOUT
*1
I
PK
EXT
C
b
2200 pF
R
b
1 kΩ
*1. VDD for E, G, J, K, L, M, P and Q types.
Figure 19 External Transistor Peripheral Circuit
The recommended Rb value is around 1 kΩ. Actually, calculate the necessary base current (Ib) from the bipolar
transistor (hFE) using
FE
PK
bh
I
I=, and select the smaller Rb value than
EXTHb
OUT
bI
4.0
I
7.0V
R−
−
= *1.
A small Rb value can increase the output current, but the efficiency decreases. Since a current may flow on the
pulse and the voltage may drop due to wiring resistance or other factors in the actual circuit, therefore the
optimum Rb value should be determined by experiment.
Connecting the speed-up capacitor (Cb) in parallel with the Rb resistance as shown in Figure 19, decreases
switching loss and improves the efficiency.
The Cb value is calculated according to 7.0fRπ2
1
C
oscb
b•••
≤.
Select a Cb value after performing sufficient evaluation since the optimum Cb value differs depending upon the
characteristics of the bipolar transistor.
*1. For E, G, J, K, L, M, P and Q type,
EXTHb
DD
bI
4.0
I
7.0V
R−
−
=.
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5. VDD / VOUT Separate Type (For E, G, J, K, L, M, P and Q Types)
The E, G, J, K, L, M, P and Q types provides separate internal circuit power supply (VDD pin) and output voltage
setting pin (VOUT pin) in the IC, making it ideal for the following applications.
(1) When changing the output voltage with external resistance.
(2) When outputting a high voltage such as +15 V or +20 V.
Choose the products in the Table 29 according to the applications (1) or (2) above.
Table 29
Output Voltage (VCC) 1.8 V ≤ VCC < 5 V 5 V ≤ VCC Reference Circuit
S-835xx18 Yes Yes
Application circuit 1 (Figure 26)
S-835xx50 − Yes
Application circuit 1 (Figure 26)
Connection to VDD pin VIN or VCC V
IN −
Cautions 1. This IC starts a step-up operation at VDD = 0.8 V, but set 1.8 ≤ VDD ≤ 10 V to stabilize the output
voltage and frequency of the oscillator. (Input a voltage of 1.8 V or more at the VDD pin for all
products with a setting less than 1.9 V.) An input voltage of 1.8 V or more at the VDD pin allows
connection of the VDD pin to either the input voltage VIN pin or output VOUT pin.
2. Choose external resistors RA and RB so as to not affect the output voltage, considering that there
is impedance between the VOUT pin and VSS pin in the IC chip. The internal resistance between
the VOUT pin and VSS pin is as follows :
(1) S-835xx18 : 2.1 to 14.8 MΩ
(2) S-835xx20 : 1.4 to 14.8 MΩ
(3) S-835xx30 : 1.4 to 14.2 MΩ
(4) S-835xx50 : 1.4 to 12.1 MΩ
3. Attach a capacitor (CC) in parallel to the RA resistance when an unstable event such as
oscillation of the output voltage occurs. Calculate CC using the following equation :
[]
kHz 20R2
1
C
A
C•••
=π
F
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Standard Circuits
（1） S-8357BxxMA, S-8357BxxUA, S-8358BxxMA, S-8358BxxUA
VOUT
EXT
VSS
PWM control circuit or
PWM / PFM switching
control circuit
Phase
compensating
circuit
Oscillation
circuit
Soft start built-in
reference power
supply
+
−
VIN 1 KΩ
2200
p
F
CIN
SD
CL
+
− +
−
IC
internal
power
supply
Remark The power supply for the IC chip is from the VOUT pin.
Figure 20
（2） S-8357BxxMC, S-8357FxxMC / BD, S-8357HxxMC / BD, S-8357NxxMC / BD, S-8358BxxMC, S-8358FxxMC / BD,
S-8358HxxMC / BD, S-8358NxxMC / BD
VOUT
V
IN
L
2200
p
F
C
IN
SD
C
L
+
− +
−
VSS
+
−
OFF/ON
EXT
Oscillation
circuit
PWM control circuit or
PWM / PFM switching
control circuit
Soft start built-in
reference power
supply
IC
internal
power
supply
Phase
compensating
circuit
1 KΩ
Remark The power supply for the IC chip is from the VOUT pin.
Figure 21
（3） S-8357ExxMC, S-8357GxxMC / BD, S-8357JxxMC / BD, S-8357PxxMC / BD, S-8358ExxMC, S-8358GxxMC / BD,
S-8358JxxMC / BD, S-8358PxxMC / BD
VOUT
EXT
VSS
V
IN
L
2200
p
F
C
IN
SD
+
−
Oscillation
circuit
PWM control circuit or
PWM / PFM switching
control circuit
Soft start built-in
reference power
supply
VDD
+
−
Phase
compensating
circui
t
C
C
C
L
+
−
R
A
R
B
IC
internal
power
supply
1 KΩ
Remark The power supply for the IC chip is from the VOUT pin.
Figure 22
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
32
（4） S-8357ExxMC, S-8357GxxMC / BD, S-8357JxxMC / BD, S-8358ExxMC, S-8358GxxMC / BD, S-8358JxxMC / BD
VOUT
EXT
VSS
VIN
L
2200
p
F
CIN
SD
CL
+
− +
−
Oscillation
circuit
PWM control circuit or
PWM / PFM switching
control circuit
Soft start built-in
reference power
supply
VDD
+
−
Phase
compensating
circuit
IC
internal
power
supply
1 KΩ
Remark The power supply for the IC chip is from the VOUT pin.
Figure 23
（5） S-8355KxxMC / BD, S-8355LxxMC / BD, S-8355MxxMC / BD, S-8355QxxMC / BD, S-8356KxxMC / BD,
S-8356LxxMC / BD, S-8356MxxMC / BD, S-8356QxxMC / BD
VOUT
EXT
VSS
V
IN
L
2200
p
F
C
IN
SD
+
− C
L
+
−
VDD
C
C
R
A
R
B
OFF/ON
Oscillation
circuit
PWM control circuit or
PWM / PFM switching
control circuit
+
−
Soft start built-in
reference power
supply
Phase
compensating
circuit
IC
internal
power
supply
1 KΩ
Remark The power supply for the IC chip is from the VOUT pin.
Figure 24
（6） S-8355KxxMC / BD, S-8355LxxMC / BD, S-8355MxxMC / BD, S-8356KxxMC / BD, S-8356LxxMC / BD,
S-8356MxxMC / BD
VOUT
V
IN
L
2200
p
F
C
IN
SD
C
L
+
− +
−
VSS
EXT
VDD
OFF/ON
Oscillation
circuit
PWM control circuit or
PWM / PFM switching
control circuit
+
−
Soft start built-in
reference power
supply
Phase
compensating
circuit
IC
internal
power
supply
1 KΩ
Remark The power supply for the IC chip is from the VOUT pin.
Figure 25
Caution The above connection diagram and constant will not guarantee successful operation. Perform
through evaluation using the actual application to set the constant.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 33
Precautions
• Mount external capacitors, the diode, and the coil as close as possible to the IC.
• Characteristics ripple voltage and spike noise occur in IC containing switching regulators. Moreover rush current flows
at the time of a power supply injection. Because these largely depend on the coil, the capacitor and impedance of
power supply used, fully check them using an actually mounted model.
• Make sure that the dissipation of the switching transistor (especially at a high temperature) does not exceed the
allowable power dissipation of the package.
• The performance of this IC varies depending on the design of the PCB patterns, peripheral circuits and external parts.
Thoroughly test all settings with your device. Also, try to use the recommended external parts. If not, contact an SII
sales person.
• Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in electrostatic
protection circuit.
• SII claims no responsibility for any disputes arising out of or in connection with any infringement by products including
this IC of patents owned by a third party.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
34
Application Circuits
1. LCD Power Supply
The following example is an application power supply circuit (15 V / 20 V output) to drive an LCD panel, and its
characteristics.
S-8356M50,
S-8356Q50
EXT
VOUT
VSS
VDD
V
OUT
C
L
C
C
R
B
R
A
TR
C
IN
V
IN
−
+
−
+
OFF/ON
L SD
Figure 26 Power Supply Circuit Example for LCD
Table 30
Condition Output Voltage IC L Type Name TR Type Name SD Type Name C
L
R
a
R
b
Cc
1 15 V S-8356M50 CDRH5D18-220 MCH3405 MA2Z748
F93
(20 V, 10
µ
F) 580 k
Ω
300 k
Ω
15 pF
2 20 V S-8356M50 CDRH5D18-220 FDN337N MA729 F93
(25 V, 10
µ
F) 575 k
Ω
200 k
Ω
15 pF
3 10 V S-8356Q50 CDRH5D18-100 MCH3405 MA2Z748
F93
(20 V, 10
µ
F) 560 k
Ω
560 k
Ω
15 pF
Caution The above connection diagram and constant will not guarantee successful operation. Perform through
evaluation using the actual application to set the constant.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 35
2. Output Characteristics of The Power Supply for LCD
The data of the step-up characteristics (a) Output current (IOUT) vs. Efficiency (η) characteristics, (b) Output current
(IOUT) vs. Output voltage (VOUT) characteristics under conditions of 1 to 3 in Table 30 is shown below.
Condition 1
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
0
20
40
60
80
100
0.01 0.1 1 10 100
η [%]
I
OUT
[mA]
V
IN
= 3.0 V
V
IN
= 5.0 V
V
IN
= 7.0 V
12
13
14
15
16
V
OUT
[V]
0.01 0.1 1 10 100
I
OUT
[mA]
V
IN
= 3.0 V
V
IN
= 5.0 V
V
IN
= 7.0 V
Condition 2
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
0
20
40
60
80
100
η [%]
0.01 0.1 1 10 100
I
OUT
[mA]
V
IN
= 3.0 V
V
IN
= 5.0 V
V
IN
= 7.0 V
14
16
18
20
22
V
OUT
[V]
0.01 0.1 1 10 100
I
OUT
[mA]
V
IN
= 3.0 V
V
IN
= 5.0 V
V
IN
= 7.0 V
Condition 3
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
0
20
40
60
80
100
η [%]
0.01 0.1 1 10 100
I
OUT
[mA]
V
IN
= 3.3 V
V
IN
= 5.0 V
7
8
9
10
11
V
OUT
[V]
0.01 0.1 1 10 100
I
OUT
[mA]
V
IN
= 3.3 V
V
IN
= 5.0 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
36
3. Using Ceramic Capacitor Example
When using small RESR parts such as ceramic capacitors for the output capacitance, mount a resistor (R1)
corresponding to the RESR in series with the ceramic capacitor (CL) as shown in Figure 27.
R1 differs depending on “L” value, the capacitance, the wiring, and the application (output load).
The following example shows a circuit using R1 = 100 mΩ, output voltage = 3.3 V, output load = 500 mA and its
characteristics.
EXT VOUT
VSS
V
OUT
SD
C
L
L
R
1
TR
V
IN
C
IN
Figure 27 Using Ceramic Capacitor Circuit Example
Table 31
Condition IC L Type Name TR Type Name SD Type Name SD Type Name R
1
1 S-8357F33 CDRH6D28-220 FDN335N M1FH3 10
µ
F
×
2 100 m
Ω
2 S-8358B50 CDRH6D28-470 FDN335N M1FH3 10
µ
F
×
2 100 m
Ω
3 S-8357N33 CDRH6D28-100 FDN335N M1FH3 10
µ
F
×
2 100 m
Ω
Caution The above connection diagram and constant will not guarantee successful operation. Perform through
evaluation using the actual application to set the constant.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 37
4. Output Characteristics of The Using Ceramic Capacitor Circuit Example
The data of the step-up characteristics (a) Output current (IOUT) vs. Efficiency (η) characteristics, (b) Output current
(IOUT) vs. Output voltage (VOUT) characteristics, (c) Output Current (IOUT) vs. Ripple voltage (Vr) under conditions of 1
to 3 in Table 31 is shown below.
Condition 1
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
0
20
40
60
80
100
η [%]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.28
3.29
3.30
3.31
3.32
V
OUT
[V]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
(c) Output Current (IOUT) vs. Ripple voltage (Vr)
0
20
40
60
80
100
Vr [mV]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 2
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
0
20
40
60
80
100
η [%]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
5.03
5.04
5.05
5.06
5.07
V
OUT
[V]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
(c) Output Current (IOUT) vs. Ripple voltage (Vr)
0
20
40
60
80
100
V
r
[mV]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
38
Condition 3
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
0
20
40
60
80
100
η [%]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.28
3.29
3.30
3.31
3.32
V
OUT
[V]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
(c) Output Current (IOUT) vs. Ripple voltage (Vr)
0
20
40
60
80
100
Vr [mV]
0.01 0.1 1 10 100
I
OUT
[mA]
1000
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 39
Characteristics (Typical Data)
1. Example of Major Temperature characteristics (Ta = −40 to +85 °C)
(1) Current Consumption 1 (I
SS1
) vs. Temperature (Ta) (V
OUT
= 3.3 V)
fOSC = 100 kHz fOSC = 300 kHz
0
10
20
30
40
50
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SS1
[µA]
0
10
20
30
40
50
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SS1
[µA]
fOSC = 600 kHz
0
20
40
60
80
100
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SS1
[µA]
(2) Current Consumption 2 (I
SS2
) vs. Temperature (Ta) (V
OUT
= 3.3 V)
fOSC = 100 kHz fOSC = 300 kHz
0
2
4
6
8
10
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SS2
[µA]
0
2
4
6
8
10
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SS2
[µA]
fOSC = 600 kHz
0
2
4
6
8
10
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SS2
[µA]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
40
(3) Current Consumption at Shutdown (I
SSS
) vs. Temperature (Ta)
fOSC = 100 kHz fOSC = 300 kHz
0
0.2
0.4
0.6
0.8
1.0
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SSS
[µA]
0
0.2
0.4
0.6
0.8
1.0
−40 −20 0 20 40 60 80 100
Ta [°C]
I
SSS
[µA]
(4) EXT Pin Output Current “H” (I
EXTH
) vs. Temperature (Ta) (5) EXT Pin Output Current “L” (I
EXTL
) vs. Temperature (Ta)
VOUT = 3.3 V, fOSC = 100 kHz VOUT = 3.3 V, fOSC = 300 kHz
−10
−20
−30
−40
−50
−60
−40 −20 0 20 40 60 80 100
Ta [°C]
I
EXTH
[mA]
0
0
10
20
30
40
50
60
−40 −20 0 20 40 60 80 100
Ta [°C]
I
EXTL
[mA]
(6) Oscillation Frequency (f
OSC
) vs. Temperature (Ta) (V
OUT
= 3.3 V)
fOSC = 100 kHz fOSC = 300 kHz
50
75
100
125
150
−40 −20 0 20 40 60 80 100
Ta [°C]
f
OSC
[kHz]
200
250
300
350
400
−40 −20 0 20 40 60 80 100
Ta [°C]
f
OSC
[kHz]
fOSC = 600 kHz
400
500
600
700
800
−40 −20 0 20 40 60 80 100
Ta [°C]
f
OSC
[kHz]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 41
(7) Maximum Duty Ratio (MaxDuty) vs. Temperature (Ta) (V
OUT
= 3.3 V)
fOSC = 100 kHz fOSC = 300 kHz
70
75
80
85
90
−40 −20 0 20 40 60 80 100
Ta [°C]
MaxDuty [%]
70
75
80
85
90
−40 −20 0 20 40 60 80 100
Ta [°C]
MaxDuty [%]
fOSC = 600 kHz
70
75
80
85
90
−40 −20 0 20 40 60 80 100
Ta [°C]
MaxDuty [%]
(8) PWM / PFM Switching Duty Ratio (PFMDuty) vs.
Temperature (Ta) (S-8356/58 Series)
(9)
OFF/ON
Pin Input Voltage “H” (V
SH
) vs. Temperature (Ta)
VOUT = 3.3 V, fOSC = 100 kHz VOUT = 3.3 V, fOSC = 300 kHz
5
10
15
20
25
−40 −20 0 20 40 60 80 100
Ta [°C]
PFMDuty [%]
0
0.2
0.4
0.6
0.8
1.0
−40 −20 0 20 40 60 80 100
Ta [°C]
VSH [V]
(10)
OFF/ON
Pin Input Voltage “L” 1 (V
SL1
) vs.
Temperature (Ta)
(11)
OFF/ON
Pin Input Voltage “L” 2 (V
SL2
) vs. Temperatuer (Ta)
VOUT = 3.3 V, fOSC = 300 kHz VOUT = 1.4 V, fOSC = 300 kHz
0
0.2
0.4
0.6
0.8
1.0
−40 −20 0 20 40 60 80 100
Ta [°C]
V
SL1
[V]
0
0.2
0.4
0.6
0.8
1.0
−40 −20 0 20 40 60 80 100
Ta [°C]
V
SL2
[V]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
42
(12) Soft Start Time (t
SS
) vs. Temperature (Ta) (V
OUT
= 3.3 V)
fOSC = 100 kHz fOSC = 300 kHz
0
2
4
6
8
−40 −20 0 20 40 60 80 100
Ta [°C]
t
SS
[ms]
0
2
4
6
8
−40 −20 0 20 40 60 80 100
Ta [°C]
tSS [ms]
fOSC = 600 kHz
0
2
4
6
8
−40 −20 0 20 40 60 80 100
Ta [°C]
t
SS
[ms]
(13) Operation Start Voltage (V
ST1
) vs. Temperature (Ta) (14) Oscillation Start Voltage (V
ST2
) vs. Temperature (Ta)
VOUT = 3.3 V, fOSC = 100 kHz VOUT = 3.3 V, fOSC = 100 kHz
0
0.2
0.4
0.6
0.8
1.0
1.2
−40 −20 0 20 40 60 80 100
Ta [°C]
VST1 [V]
0
0.2
0.4
0.6
0.8
1.0
1.2
−40 −20 0 20 40 60 80 100
Ta [°C]
V
ST2
[V]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 43
(15) Output Voltage (V
OUT
) vs. Temperature (Ta) (V
OUT
= 3.3 V)
fOSC = 100 kHz fOSC = 300 kHz
3.20
3.25
3.30
3.35
3.40
−40 −20 0 20 40 60 80 100
Ta [°C]
V
OUT
[V]
3.20
3.25
3.30
3.35
3.40
−40 −20 0 20 40 60 80 100
Ta [°C]
V
OUT
[V]
fOSC = 600 kHz
3.20
3.25
3.30
3.35
3.40
−40 −20 0 20 40 60 80 100
Ta [°C]
V
OUT
[V]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
44
2. Examples of Major Power Supply Dependence Characteristics (Ta = 25 °C)
(1) Current Consumption 1 (I
SS1
) vs. Power Supply Voltage (V
DD
), Current Consumption 2 (I
SS2
) vs. Power Supply Voltage (V
DD
)
(V
OUT
= 3.3 V)
fOSC = 300 kHz fOSC = 600 kHz
0
10
20
30
40
50
0 2 4 6 8 10
V
DD
[V]
I
SS1,2
[µA]
0
20
40
60
80
100
0 2 4 6 8 10
V
DD
[V]
I
SS1,2
[µA]
(2) Current Consumption at Shutdown (I
SSS
) vs. Power Supply Voltage (V
DD
)
VOUT = 3.3 V, fOSC = 300 kHz
0
0.2
0.4
0.6
0.8
1.0
I
SSS
[µA]
0 2 4 6 8 10
V
DD
[V]
(3) Oscillation Friquency (f
OSC
) vs. Power Supply Voltage (V
DD
)
fOSC = 100 kHz fOSC = 300 kHz
20
40
60
80
100
120
0 2 4 6 8 10
V
DD
[V]
f
OSC
[kHz]
0 2 4 6 8 10
V
DD
[V]
f
OSC
[kHz]
60
120
180
240
300
360
fOSC = 600 kHz
0 2 4 6 8 10
V
DD
[V]
f
OSC
[kHz]
120
240
360
480
600
720
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 45
(4) Maximum Duty Ratio (MaxDuty) vs. Power Supply Voltage (V
DD
)
fOSC = 100 kHz fOSC = 300 kHz
0 2 4 6 8 10
V
DD
[V]
50
60
70
80
90
100
MaxDuty [%]
0 2 4 6 8 10
V
DD
[V]
50
60
70
80
90
100
MaxDuty [%]
fOSC = 600 kHz
0 2 4 6 8 10
V
DD
[V]
50
60
70
80
90
100
MaxDuty [%]
(5) EXT Pin Output Current “H” (I
EXTH
) vs.
Power Supply Voltage (V
DD
)
(6) EXT Pin Output Current “L” (I
EXTL
) vs.
Power Supply Voltage (V
DD
)
0 2 4 6 8 10
V
DD
[V]
0
−20
−40
−60
−80
−100
I
EXTH
[mA]
0 2 4 6 8 10
V
DD
[V]
0
−20
−40
−60
−80
−100
I
EXTL
[mA]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
46
(7) Output Voltage (V
OUT
) vs. Power Supply Voltage (V
DD
) (V
DD
Separate Type, V
OUT
= 3.3 V, V
IN
= 1.98 V, I
OUT
=
66 mA)
fOSC = 100 kHz fOSC = 300 kHz
0 2 4 6 8 10
V
DD
[V]
1.5
2.0
2.5
3.0
3.5
V
OUT
[V]
0 2 4 6 8 10
V
DD
[V]
1.5
2.0
2.5
3.0
3.5
V
OUT
[V]
fOSC = 600 kHz
0 2 4 6 8 10
V
DD
[V]
1.5
2.0
2.5
3.0
3.5
V
OUT
[V]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 47
3. Output Waveforms
(1) S-8358B33MC
IOUT = 1 mA IOUT = 20 mA
−25
−20
−15
−10−5 0 5 10 15 20 25
time [
µ
s]
4
2
0
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
4
2
0
−25
−20
−15
−10
−5 0 5 10 15 20 25
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
IOUT = 100 mA IOUT = 200 mA
4
2
0
3.40
3.35
3.30
3.25
−25
−20
−15
−10−5 0 5 10 15 20 25
time [
µ
s]
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
4
2
0
−25
−20
−15
−10
−5 0 5 10 15 20 25
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
(2) S-8358F33MC
IOUT = 1 mA IOUT = 10 mA
4
2
0
3.40
3.35
3.30
3.25
−10
−8 −6 −4−2 0 2 4 6 8 10
time [
µ
s]
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
4
2
0
−10 −8−6−4 −2 0 2 4 6 8 10
3.40
3.35
3.30
3.25
time [
µ
s]
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
IOUT = 100 mA IOUT = 200 mA
4
2
0
−10
−8 −6 −4−2 0 2 4 6 8 10
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
4
2
0
−10−8−6−4 −2 0 2 4 6 8 10
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
48
(3) S-8358N33MC
IOUT = 1 mA IOUT = 10 mA
4
2
0
−5 −4 −3 −2−1 0 1 2 3 4 5
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
4
2
0
−5−4−3−2 −1 0 1 2 3 4 5
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
IOUT = 100 mA IOUT = 200 mA
4
2
0
−5 −4 −3 −2−1 0 1 2 3 4 5
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
4
2
0
−5−4−3−2 −1 0 1 2 3 4 5
time [
µ
s]
3.40
3.35
3.30
3.25
Output voltage
[0.05 V / div]
CONT voltage
[2.0 V / div]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 49
4. Examples of Transient Response Characteristics
(1) Power-On (VIN : 0 V→2 V)
100 kHz, IOUT = 1 mA 100 kHz, IOUT = 100 mA
0
2
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
V
IN
[V]
0
2
4
V
OUT
[V]
V
IN
V
OUT
0
2
V
IN
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
IN
V
OUT
300 kHz, IOUT = 1 mA 300 kHz, IOUT = 100 mA
0
2
V
IN
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
IN
V
OUT
0
2
V
IN
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
IN
V
OUT
600 kHz, IOUT = 1 mA 600 kHz, IOUT = 100 mA
0
2
V
IN
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
IN
V
OUT
0
2
V
IN
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
IN
V
OUT
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
50
(2) OFFON/ Pin Response ( OFF/ON
V : 0 V → 2.0 V)
100 kHz, IOUT = 1 mA 100 kHz, IOUT = 100 mA
0
2
V
ON/OFF
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
OUT
V
ON/OFF
0
2
V
ON/OFF
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
ON/OFF
V
OUT
300 kHz, IOUT = 1 mA 300 kHz, IOUT = 100 mA
0
2
V
ON/OFF
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
ON/OFF
V
OUT
0
2
V
ON/OFF
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
ON/OFF
V
OUT
600 kHz, IOUT = 1 mA 600 kHz, IOUT = 100 mA
0
2
V
ON/OFF
[V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
V
OUT
[V]
V
ON/OFF
V
OUT
0
2
VON/OFF [V]
−1 0 1 2 3 4 5 6 7 8 9
time [ms]
0
2
4
VOUT [V]
VON/OFF
VOUT
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 51
(3) Load Fluctuations
100 kHz, IOUT : 100 µA → 100 mA 100 kHz, IOUT : 100 mA → 100 µA
−0.2 0 0.2
0.4
0.6 0.8
1.0
1.2
1.4
1.61.8
time [ms]
3.00
3.20
3.40
3.60
V
OUT
[0.2 V / div]
100
µ
A
I
OUT
100 mA
V
OUT
[0.2 V / div]
100
µ
A
I
OUT
100 mA
3.20
3.40
3.60
3.80
−10 010 20 30 40 50 60 70 80 90
time [ms]
300 kHz, IOUT : 100 µA → 100 mA 300 kHz, IOUT : 100 mA → 100 µA
V
OUT
[0.2 V / div]
100
µ
A
I
OUT
100 mA
−0.5 0 0.5
1.0
1.5 2.0
2.5 3.0
3.5
4.04.5
time [ms]
3.00
3.20
3.40
3.60
V
OUT
[0.2 V / div]
100
µ
A
I
OUT
100 mA
3.20
3.40
3.60
3.80
−10 010 20 30 40 50 60 70 80 90
time [ms]
600 kHz, IOUT : 0.1 mA → 100 mA 600 kHz, IOUT : 100 mA → 0.1 mA
V
OUT
[0.2 V / div]
100
µ
A
I
OUT
100 mA
3.00
3.20
3.40
3.60
−0.2 0 0.2
0.4
0.6 0.8
1.0
1.2
1.4
1.61.8
time [ms]
V
OUT
[0.2 V / div]
100
µ
A
I
OUT
100 mA
3.00
3.20
3.60
3.80
−0.5 00.5 1.0 1.5 2.5 3.0
2.0
time [ms]
3.40
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
52
(4) Input Voltage Fluctuations (IOUT = 100 mA)
100 kHz, VIN = 1.98 V → 2.64 V 100 kHz, VIN = 2.64 V → 1.98 V
3.25
3.30
3.35
3.40
3.45
3.0
2.5
2.0
1.5
−0.2 0 0.2
0.4
0.6
0.81.0 1.2
1.4
1.6
1.8
time [ms]
V
OUT
[V]
V
IN
[V]
3.0
2.5
2.0
1.5
V
IN
[V]
−0.2 00.20.40.6 0.8
1.0 1.2
1.4
1.6
1.8
time [ms]
3.25
3.30
3.35
3.40
3.45
V
OUT
[V]
300 kHz, VIN = 1.98 V → 2.64 V 300 kHz, VIN = 2.64 V → 1.98 V
3.0
2.5
2.0
1.5
−0.2 0 0.2
0.4
0.6
0.81.0 1.2
1.4
1.6
1.8
time [ms]
3.25
3.30
3.35
3.40
3.45
V
IN
[V]
V
OUT
[V]
3.0
2.5
2.0
1.5
V
IN
[V]
−0.2 00.20.40.6 0.8
1.0 1.2
1.4
1.6
1.8
time [ms]
3.25
3.30
3.35
3.40
3.45
V
OUT
[V]
600 kHz, VIN = 1.98 V → 2.64 V 600 kHz, VIN = 2.64 V → 1.98 V
3.0
2.5
2.0
1.5
V
IN
[V]
−0.2 0 0.2
0.4
0.6
0.81.0 1.2
1.4
1.6
1.8
time [ms]
3.25
3.30
3.35
3.40
3.45
V
OUT
[V]
3.0
2.5
2.0
1.5
V
IN
[V]
−0.2 00.20.40.6 0.8
1.0 1.2
1.4
1.6
1.8
time [ms]
3.25
3.30
3.35
3.40
3.45
V
OUT
[V]
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 53
Reference Data
Use this reference data to choose the external parts. This reference data makes it possible to choose the recommended
external part based on the application and characteristics data.
1. External Parts for Reference Data
Table 32 Efficiency vs. Output Current Characteristics and Output Voltage vs. Output Current Characteristics for External
Condition Product Name Oscillation
Frequency
Output
Voltage
Control
System Inductor Transistor Diode Output capacitor
1 S-8357F33 300 kHz 3.3 V PWM CDRH104R-220 S-90N0312SMA M1FH3 F93 (16 V, 47
µ
F)
×
2
2 S-8357F50 300 kHz 5.0 V PWM
3 S-8356M50 300 kHz 5.0 V PWM/PFM
4 S-8357B33 100 kHz 3.3 V PWM CDRH104R-470
5 S-8358B33 100 kHz 3.3 V PWM/PFM S-90N0442SUA
6 S-8357B50 100 kHz 5.0 V PWM
7 S-8356M50 300 kHz 5.0 V PWM/PFM CDRH8D28-220 S-90N0212SMA F93 (16 V, 47
µ
F)
8 S-8357B33 100 kHz 3.3 V PWM CDRH8D28-470
9 S-8358B33 100 kHz 3.3 V PWM/PFM
10 S-8357B50 100 kHz 5.0 V PWM
11 S-8357F33 300 kHz 3.3 V PWM CXLP120-220 MA2Z748 F92 (6.3 V, 47
µ
F)
12 S-8356M50 300 kHz 5.0 V PWM/PFM
13 S-8357N33 600 kHz 3.3 V PWM CDRH8D28-100 M1FH3 F93 (16 V, 47
µ
F)
14 S-8357N50 600 kHz 5.0 V PWM
15 S-8356Q33 600 kHz 3.3 V PWM/PFM
16 S-8356Q50 600 kHz 5.0 V PWM/PFM
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
54
The properties of the external parts are shown below.
Table 33 Properties of External Parts
Compornent Product Name Manufacturer Characteristics
Inductor CDRH104R-220 Sumida Corporation 22 µH, DCR*1 = 73 mΩ, IMAX.*2 = 2.5 A,
Component height = 4.0 mm
CDRH104R-470 47 µH, DCR*1 = 128 mΩ, IMAX.*2 = 1.9 A,
Component height = 4.0 mm
CDRH8D28-100 10 µH, DCR*1 = 47 mΩ, IMAX.*2 = 2.7 A,
Component height = 3.0 mm
CDRH8D28-220 22 µH, DCR*1 = 99 mΩ, IMAX.*2 = 1.8 A,
Component height = 3.0 mm
CDRH8D28-470 47 µH, DCR*1 = 195 mΩ, IMAX.*2 = 1.25 A,
Component height = 3.0 mm
CXLP120-220 Sumitomo Special Metals Co., Ltd. 22 µH, DCR*1 = 590 mΩ, IMAX.*2 = 0.55 A,
Component height = 1.2 mm
Diode M1FH3 Shindengen Electric Manufacturing Co., Ltd. VF*3 = 0.3 V, IF*4 = 1.5 A
MA2Z748 Matsushita Electric Industrial Co., Ltd. VF*3 = 0.4 V, IF*4 = 0.3 A
F93 Nichicon Corporation 16 V, 47 µF Capacitor
(Output Capacitance) F92 6.3 V, 47 µF
Transistor
(Nch FET) S-90N0212SMA Seiko Instruments Inc.
VDSS *5 = 20 V max., VGSS*6 = 12 V max.,
CISS*7 = 190 pF, RDS(ON)*8 = 0.16 Ω max.
(VGS*9 = 2.5 V, ID*10 = 0.5 A)
S-90N0312SMA
VDSS *5 = 20 V max., VGSS*6 = 8 V max.,
CISS*7 = 170 pF, RDS(ON)*8 = 0.14 Ω max.
(VGS*9 = 2.5 V, ID*10 = 0.5 A)
S-90N0442SUA
VDSS *5 = 20 V max.,VGSS*6 = 8 V max.,
CISS*7 = 390 pF, RDS(ON)*8 = 0.07 Ω max.
(VGS*9 = 2.5 V, ID*10 = 2 A)
*1. Direct current resistance
*2. Maximum allowable current
*3. Forward voltage
*4. Forward current
*5. Drain source voltage
*6. Gate source voltage
*7. Input capacitance
*8. Drain source ON-resistance
*9. Gate source voltage
*10. Drain current
Caution The values shown in the characteristics column of Table 33 above are based on the materials provided by
each manufacture. However, consider the characteristics of the original materials when using the above
products.
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 55
2. Output Current (IOUT) vs. Efficiency (η) Characteristics, Output Current (IOUT) vs. Output Voltage (VOUT) Characteristics
The following shows the actual (a) Output current (IOUT) vs. Efficiency (η) characteristics and (b) Output current (IOUT)
vs. Output voltage (VOUT) characteristics under the conditions of No. 1 to 16 in Table 32.
Condition 1 S-8357F33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
1 10 100 10000.1
η [%]
IOUT [mA]
VIN = 0.9 V
VIN = 1.8 V
VIN = 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
1 10 100 10000.1
I
OUT
[mA]
V
OUT
[V]
Condition 2 S-8357F50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
1 10 100 10000.1
I
OUT
[mA]
V
OUT
[V]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 3 S-8356M50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 4 S-8357B33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
VOUT [V]
1 10 100 10000.1
IOUT [mA]
VIN = 0.9 V
VIN = 1.8 V
VIN = 2.7 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
56
Condition 5 S-8358B33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 6 S-8357B50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 7 S-8357M50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
IOUT [mA]
VIN = 2.0 V
VIN = 3.0 V
VIN = 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 8 S-8357B33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 57
Condition 9 S-8358B33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 10 S-8357B50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 11 S-8357F33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 12 S-8356M50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
58
Condition 13 S-8357N33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
3.0
3.1
3.2
3.3
3.4
3.5
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 14 S-8357N50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 15 S-8356Q33
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
V
IN
= 1.8 V
V
IN
= 2.7 V
1 10 100 10000.1
I
OUT
[mA]
3.0
3.1
3.2
3.3
3.4
3.5
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 16 S-8356Q50
(a) Output current (IOUT) vs. Efficiency (η) (b) Output current (IOUT) vs. Output voltage (VOUT)
20
40
60
80
100
η [%]
1 10 100 10000.1
IOUT [mA]
VIN = 3.0 V
VIN = 4.0 V
4.7
4.8
4.9
5.0
5.1
5.2
V
OUT
[V]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 3.0 V
V
IN
= 4.0 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
Rev.4.2_01 S-8355/56/57/58 Series
Seiko Instruments Inc. 59
3. Output Current (IOUT) vs. Ripple Voltage (Vr) Characteristics
The following shows the actual Output current (IOUT) vs. Ripple voltage (Vr) characteristics and (b) Output current
(IOUT) vs. Output voltage (VOUT) characteristics under the conditions of No. 1 to 16 in Table 32.
Condition 1 S-8357F33 Condition 2 S-8357F50
0
50
100
150
Vr [mV]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
1 10 100 10000.1
I
OUT
[mA]
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 3 S-8356M50 Condition 4 S-8357B33
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
Condition 5 S-8358B33 Condition 6 S-8357B50
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 7 S-8356M50 Condition 8 S-8357B33
0
50
100
150
Vr [mV]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
1 10 100 10000.1
I
OUT
[mA]
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
STEP-UP, SUPER-SMALL PACKAGE, 600 kHz, PWM CONTROL or PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8355/56/57/58 Series Rev.4.2_01
Seiko Instruments Inc.
60
Condition 9 S-8358B33 Condition 10 S-8357B50
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 11 S-8357F33 Condition 12 S-8356M50
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
0
50
100
150
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 13 S-8357N33 Condition 14 S-8357N50
20
40
60
80
100
0
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 0.9 V
V
IN
= 1.8 V
V
IN
= 2.7 V
20
40
60
80
100
0
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 2.0 V
V
IN
= 3.0 V
V
IN
= 4.0 V
Condition 15 S-8356Q33 Condition 16 S-8356Q50
20
40
60
80
100
0
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 1.8 V
V
IN
= 2.7 V
20
40
60
80
100
0
Vr [mV]
1 10 100 10000.1
I
OUT
[mA]
V
IN
= 3.0 V
V
IN
= 4.0 V
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
2.9±0.2
0.95±0.1
1.9±0.2
+0.1
-0.05
0.16
0.4±0.1
1
23
No. MP003-A-P-SD-1.1
MP003-A-P-SD-1.1
SOT233-A-PKG Dimensions
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
1.6±0.1
0.25±0.05
4.0±0.1
2.0±0.1
4.0±0.1
1.5 +0.1
-0.05
1.1±0.1
2.85±0.2
No. MP003-A-C-SD-1.1
MP003-A-C-SD-1.1
SOT233-A-Carrier Tape
Feed direction
1
23
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
(60°)
(60°)
ø13±0.2
12.5max.
9.0±0.3
QTY. 3,000
No. MP003-A-R-SD-1.1
MP003-A-R-SD-1.1
SOT233-A-Reel
Enlarged drawing in the central part
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
2.9±0.2
1.9±0.2
0.95±0.1
0.4±0.1
0.16 +0.1
-0.06
123
4
5
No. MP005-A-P-SD-1.2
MP005-A-P-SD-1.2
SOT235-A-PKG Dimensions
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
ø1.5 +0.1
-0 2.0±0.05
ø1.0 +0.2
-0 4.0±0.1
1.4±0.2
0.25±0.1
3.2±0.2
123
45
No. MP005-A-C-SD-2.1
MP005-A-C-SD-2.1
SOT235-A-Carrier Tape
Feed direction
4.0±0.1(10 pitches:40.0±0.2)
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
12.5max.
9.0±0.3
ø13±0.2
(60°) (60°)
QTY. 3,000
No. MP005-A-R-SD-1.1
MP005-A-R-SD-1.1
SOT235-A-Reel
Enlarged drawing in the central part
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
0.4±0.05
1.5±0.1
4.5±0.1
1.6±0.2
1.5±0.1 1.5±0.1
0.45±0.1
0.4±0.1
0.4±0.1
45°
312
No. UP003-A-P-SD-1.1
UP003-A-P-SD-1.1
SOT893-A-PKG Dimensions
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
2.0±0.1
0.3±0.05
8.0±0.1
ø1.5+0.1
-0
2.0±0.05
ø1.5+0.1
-0
4.75±0.1
5° max.
No. UP003-A-C-SD-1.1
UP003-A-C-SD-1.1
SOT893-A-Carrier Tape
Feed direction
4.0±0.1(10 pitches : 40.0±0.2)
No.
TITLE
SCALE
UNIT mm
Seiko Instruments Inc.
13.0±0.3
16.5max.
(60°)
(60°)
QTY. 1,000
No. UP003-A-R-SD-1.1
UP003-A-R-SD-1.1
SOT893-A-Reel
Enlarged drawing in the central part
1.8±0.15
0.5±0.1 0.5±0.1
0.8±0.05
0.14±0.05
R(0.075)
0.2±0.08
(0.125)
123
456
SNB6B-A-PKG Dimensions
No. BD006-A-P-SD-3.0
Seiko Instruments Inc.
No.
TITLE
SCALE
UNIT mm
BD006-A-P-SD-3.0
The heatsink of back side has different electric
potential depending on the product.
Confirm specifications of each product.
Do not use it as the function of electrode.
0.2±0.08
No.
TITLE
SCALE
UNIT mm
4.0±0.1
2.0±0.05
4.0±0.1
ø1.5±0.1
2.2±0.1
1.1±0.1
0.25±0.05
ø1.1±0.1
Seiko Instruments Inc.
Feed direction
SNB6B-A-Carrier Tape
No. BD006-A-C-SD-2.1
BD006-A-C-SD-2.1
1
2
3
6
5
4
QTY. 3,000
No.
TITLE
SCALE
UNIT mm
12.5max.
9.0±0.3
ø13±0.2
Seiko Instruments Inc.
Enlarged drawing in the central part
SNB6B-A-Reel
No. BD006-A-R-SD-1.1
BD006-A-R-SD-1.1
•
The information described herein is subject to change without notice.
• Seiko Instruments Inc. is not responsible for any problems caused by circuits or diagrams described herein
whose related industrial properties, patents, or other rights belong to third parties. The application circuit
examples explain typical applications of the products, and do not guarantee the success of any specific
mass-production design.
• When the products described herein are regulated products subject to the Wassenaar Arrangement or other
agreements, they may not be exported without authorization from the appropriate governmental authority.
• Use of the information described herein for other purposes and/or reproduction or copying without the
express permission of Seiko Instruments Inc. is strictly prohibited.
• The products described herein cannot be used as part of any device or equipment affecting the human
body, such as exercise equipment, medical equipment, security systems, gas equipment, or any apparatus
installed in airplanes and other vehicles, without prior written permission of Seiko Instruments Inc.
• Although Seiko Instruments Inc. exerts the greatest possible effort to ensure high quality and reliability, the
failure or malfunction of semiconductor products may occur. The user of these products should therefore
give thorough consideration to safety design, including redundancy, fire-prevention measures, and
malfunction prevention, to prevent any accidents, fires, or community damage that may ensue.
