FUJITSU MICROELECTRONICS
DATA SHEET
Copyright©2008 FUJITSU MICROELECTRONICS LIMITED All rights reserved
2008.12
ASSP for Power Management Applications
(General-Purpose DC/DC Converter)
2ch PFM/PWM DC/DC converter IC
with synchronous rectification
MB39A136
■DESCRIPTION
MB39A136 is 2ch step-down DC/DC converter IC of the current mode N-ch/N-ch synchronous rectification meth-
od. It contains the enhanced protection features, and supports the symmetrical-phase method and the ceramic
capacitor. MB39A136 realizes rapid response, high efficiency, and low ripple voltage, and its high-frequency
operation enables the miniaturization of inductors and I/O capacitors.
■FEATURES
• High efficiency
• For frequency setting by external resistor : 100 kHz to 1 MHz
• Error Amp threshold voltage : 0.7 V ± 1.0%
• Minimum output voltage value : 0.7 V
• Wide range of power-supply voltage : 4.5 V to 25 V
• PFM/PWM auto switching mode and fixed PWM mode selectable
• Supports Symmetrical-Phase method
• With built-in over voltage protection function
• With built-in under voltage protection function
• With built-in over current protection function
• With built-in over-temperature protection function
• With built-in soft start/stop circuit without load dependence
• With built-in synchronous rectification type output steps for N-ch MOS FET
• Standby current : 0 [µA] Typ
• Small package : TSSOP-24
■APPLICATION
• Digital TV
• Photocopiers
• Surveillance cameras
• Set-top boxes (STB)
• DVD players, DVD recorders
•Projectors
• IP phones
• Vending machine
• Consoles and other non-portable devices
DS04-27262-2E
MB39A136
2DS04-27262-2E
■PIN ASSIGNMENT
(TOP VIEW)
(FPT-24P-M09)
24
23
22
21
20
19
18
17
16 LX2
15
14
13
CB1
DRVH1
LX1
DRVL1
VCC
VB
GND
DRVL2
DRVH2
CB2
MODE
1
2
3
4
5
6
7
8
9
10
11
12
CTL1
CS1
FB1
COMP1
ILIM1
RT
VREF
CTL2
ILIM2
COMP2
FB2
CS2
MB39A136
DS04-27262-2E 3
■PIN DESCRIPTION
Pin No. Symbol I/O Description
1 CTL1 I CH1 control pin.
2 CS1 I CH1 soft-start time setting capacitor connection pin.
3 FB1 I CH1 Error amplifier inverted input pin.
4 COMP1 O CH1 error amplifier output pin.
5 ILIM1 I CH1 over current detection level setting voltage input pin.
6RT⎯Oscillation frequency setting resistor connection pin.
7 VREF O Reference voltage output pin.
8 CTL2 I CH2 control pin.
9 ILIM2 I CH2 over current detection level setting voltage input pin.
10 COMP2 O CH2 error amplifier output pin.
11 FB2 I CH2 Error amplifier inverted input pin.
12 CS2 I CH2 soft-start time setting capacitor connection pin.
13 MODE I
PFM/PWM switch pin. (CH1 and CH2 commonness) It becomes fixed
PWM operation with the VREF connection, and it becomes PFM/PWM
operation with the GND connection.
14 CB2 ⎯CH2 connection pin for boot strap capacitor.
15 DRVH2 O CH2 output pin for external high-side FET gate drive.
16 LX2 ⎯CH2 inductor and external high-side FET source connection pin.
17 DRVL2 O CH2 output pin for external low-side FET gate drive.
18 GND ⎯Ground pin.
19 VB O Bias voltage output pin.
20 VCC ⎯Power supply pin for reference voltage and control circuit.
21 DRVL1 O CH1 output pin for external low-side FET gate drive.
22 LX1 ⎯CH1 inductor and external high-side FET source connection pin.
23 DRVH1 O CH1 output pin for external high-side FET gate drive.
24 CB1 ⎯CH1 connection pin for boot strap capacitor.
MB39A136
4DS04-27262-2E
■BLOCK DIAGRAM
+
−
−
+
+−
+
+
−
−
+
−
+
FB1
COMP1
CS1
CS2
COMP2
FB2
ILIM1
ILIM2
3
4
2
11
10
12
5
9
5.5
µA
VREF
<Soft-Start,
Soft-Stop>
/uvlo
ovp_out
<CH1>
13MODE
70 kΩ
ctl1
/uvp_out
/otp_out
intref
<I Comp.>
<Error Amp>
ovp1
intref
x 0.7 V
intref
x 1.15 V
<OVP Comp.>
uvp1
<UVP Comp.>
Vs
ovp1
ovp2
<CH2>
uvp1
uvp2
50 µs
delay
512/f
OSC
delay
ovp_out
uvp_out
SQ
R
SQ
R
VB
UVLO
<UVLO>
VREF
UVLO
uvlo
H:UVLO
release
OTP
otp_out
Drive
Logic
Hi-side
Drive
Bias
Reg.
RS-FF
20VCC
S
QR
Clock
generator
ch.1 180° out of phase
6RT
ch.2
<PFM Comp. >
pfm1
pfm2
2.0 V
CLK VB
Lo-side
Drive Level
Converter
<Di Comp.>
23
22
24 CB1
DRVH1
LX1
19 VB
21 DRVL1
1
15
16
14
17
CB2
DRVH2
DRVL2
LX2
CTL1
CTL2
8
<REF> <CTL>
intref
(3.3 V)
718
ON/OFF
VB
GNDVREF
ctl1, ctl2
The configuration of a control circuit is the same as that of CH1.
MB39A136
DS04-27262-2E 5
■ABSOLUTE MAXIMUM RATINGS
WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current,
temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings.
Parameter Symbol Conditions Rating Unit
Min Max
Power-supply voltage VVCC VCC pin ⎯27 V
CB pin input voltage VCB CB1, CB2 pins ⎯32 V
LX pin input voltage VLX LX1, LX2 pins ⎯27 V
Voltage between CB and LX VCBLX ⎯⎯7V
Control input voltage VICTL1, CTL2 pins ⎯27 V
Input voltage
VFB FB1, FB2 pins ⎯VVREF + 0.3 V
VILIM ILIM1, ILIM2 pins ⎯VVREF + 0.3 V
VCSx CS1, CS2 pins ⎯VVREF + 0.3 V
VMODE MODE pin ⎯VVB + 0.3 V
Output current IOUT DC DRVL1, DRVL2 pins,
DRVH1, DRVH2 pins ⎯60 mA
Power dissipation PDTa ≤ + 25 °C⎯1644 mW
Storage temperature TSTG ⎯ − 55 + 150 °C
MB39A136
6DS04-27262-2E
■RECOMMENDED OPERATING CONDITIONS
WARNING: The recommended operating conditions are required in order to ensure the normal operation of
the semiconductor device. All of the device's electrical characteristics are warranted when the
device is operated within these ranges.
Always use semiconductor devices within their recommended operating condition ranges.
Operation outside these ranges may adversely affect reliability and could result in device failure.
No warranty is made with respect to uses, operating conditions, or combinations not represented
on the data sheet. Users considering application outside the listed conditions are advised to contact
their representatives beforehand.
Parameter Symbol Conditions Value Unit
Min Typ Max
Power supply voltage VVCC ⎯4.5 ⎯25.0 V
CB pin
input voltage VCB ⎯⎯⎯30 V
Reference voltage
output current IVREF ⎯ − 100 ⎯⎯µA
Bias output current IVB ⎯ − 1 ⎯⎯mA
CTL pin input voltage VICTL1, CTL2 pins 0 ⎯25 V
Input voltage
VFB FB1, FB2 pins 0 ⎯VVREF V
VILIM ILIM1, ILIM2 pins 0.3 ⎯1.94 V
VCS CS1, CS2 pins 0 ⎯VVREF V
VMODE MODE pin 0 ⎯VVREF V
Peak output current IOUT
DRVH1, DRVH2 pins
DRVL1, DRVL2 pins
Duty ≤ 5% (t = 1/fOSC × Duty)
− 1200 ⎯ + 1200 mA
Operation frequency
range fOSC ⎯100 500 1000 kHz
Timing resistor RRT RT pin ⎯47 ⎯kΩ
Soft start capacitor CCS CS1, CS2 pins 0.0075 0.0180 ⎯µF
CB pin capacitor CCB CB1, CB2 pins ⎯0.1 1.0 µF
Reference voltage
output capacitor CVREF VREF pin ⎯0.1 1.0 µF
Bias voltage output
capacitor CVB VB pin ⎯2.2 10 µF
Operating ambient
temperature Ta ⎯ − 30 + 25 + 85 °C
MB39A136
DS04-27262-2E 7
■ELECTRICAL CHARACTERISTICS
(Ta = + 25 °C, VCC pin = 15 V, CTL pin = 5 V, VREF pin = 0 A, VB pin = 0A)
(Continued)
Parameter Symbol Pin
No. Conditions Value Unit
Min Typ Max
Reference
Voltage
Block
[REF]
Output voltage VVREF 7⎯3.24 3.30 3.36 V
Input stability VREF
LINE 7 VCC pin = 4.5 V to 25 V ⎯110mV
Load stability VREF
LOAD 7VREF pin = 0 A to
− 100 µA⎯110mV
Short-circuit output
current
VREF
IOS 7 VREF pin = 0 V − 14.5 − 10.0 − 7.5 mA
Bias Voltage
Block
[VB Reg.]
Output voltage VVB 19 ⎯4.85 5.00 5.15 V
Input stability VB
LINE 19 VCC pin = 6 V to 25 V ⎯10 100 mV
Load stability VB
LOAD 19 VB pin = 0 A to − 1 mA ⎯10 100 mV
Short-circuit output
current
VB
IOS 19 VB pin = 0 V − 200 − 140 − 100 mA
Under volt-
age Lockout
Protection
Circuit Block
[UVLO]
Threshold voltage VTLH1 19 VB pin 4.0 4.2 4.4 V
VTHL1 19 VB pin 3.4 3.6 3.8 V
Hysteresis width VH1 19 VB pin ⎯0.6* ⎯V
Threshold
voltage
VTLH2 7 VREF pin 2.7 2.9 3.1 V
VTHL2 7 VREF pin 2.5 2.7 2.9 V
Hysteresis width VH2 7VREF pin ⎯0.2* ⎯V
Soft-start /
Soft-stop
Block
[Soft-Start,
Soft-Stop]
Charge current ICS 2, 12 CTL1, CTL2 pins = 5 V,
CS1, CS2 pins = 0 V − 7.9 − 5.5 − 4.2 µA
Soft-start
end voltage VCS 2, 12 CTL1, CTL2 pins = 5 V 2.2 2.4 2.6 V
Electrical discharge
resistance at
soft-stop
RDISCG 2, 12 CTL1, CTL2 pins = 0 V,
CS1, CS2 pins = 0.5 V 49 70 91 kΩ
Soft-stop
end voltage VDISCG 2, 12 CTL1, CTL2 pins = 0 V ⎯0.1* ⎯V
Clock
Generator
Block
[OSC]
Oscillation
frequency fOSC 6 RT pin = 47 kΩ450 500 550 kHz
Oscillation
frequency when
under voltage is
detected
fSHORT 6 RT pin = 47 kΩ⎯62.5 ⎯kHz
Frequency
Temperature
variation
df/dT 6 Ta = − 30 °C to + 85 °C⎯3* ⎯%
MB39A136
8DS04-27262-2E
(Ta = + 25 °C, VCC pin = 15 V, CTL pin = 5 V, VREF pin = 0 A, VB pin = 0 A)
(Continued)
Parameter Symbol Pin
No. Conditions Value Unit
Min Typ Max
Error Amp
Block
[Error Amp1,
Error Amp2]
Threshold
voltage
EVTH 3, 11 ⎯0.693 0.700 0.707 V
EVTHT 3, 11 Ta = − 30 °C to + 85 °C 0.689* 0.700* 0.711* V
Input current IFB 3, 11 FB1, FB2 pins = 0 V − 0.1 0 + 0.1 µA
Output current
ISOURCE 4, 10
FB1, FB2 pins = 0 V,
COMP1, COMP2 pins =
1 V
− 390 − 300 − 210 µA
ISINK 4, 10
FB1, FB2 pins =
VREF pin,
COMP1, COMP2 pins =
1 V
8.4 12.0 16.8 mA
Output clamp
voltage VILIM 4, 10 FB1, FB2 pins = 0 V,
ILIM1, ILIM2 pins = 1.5 V 1.35 1.50 1.65 V
ILIM pin
input current IILIM 5, 9 FB1, FB2 pins = 0 V,
ILIM1, ILIM2 pins = 1.5 V − 10 + 1 µA
Over-voltage
Protection
Circuit Block
[OVP Comp.]
Over-voltage
detecting
voltage
VOVP 3, 11 FB1, FB2 pins 0.776 0.805 0.835 V
Over-voltage
detection time tOVP 3, 11 ⎯49 70 91 µs
Under-voltage
Protection
Circuit Block
[UVP Comp.]
Under-voltage
detecting
voltage
VUVP 3, 11 FB1, FB2 pins 0.450 0.490 0.531 V
Under-voltage
detection time tUVP 3, 11 ⎯⎯
512/
fOSC ⎯s
Over-tempera-
ture Protection
Circuit Block
[OTP]
Detection
temperature
TOTPH ⎯Junction temperature ⎯ + 160* ⎯ °C
TOTPL ⎯Junction temperature ⎯ + 135* ⎯ °C
PFM Control
Circuit Block
(MODE)
Synchronous
rectification stop
voltage
VTHLX 22, 16 LX1, LX2 pins ⎯0* ⎯mV
PFM/PWM
mode condition VPFM 13 MODE pin 0 ⎯1.4 V
Fixed PWM
mode
condition
VPWM 13 MODE pin 2.2 ⎯VVREF V
MODE pin input
current IMODE 13 MODE pin = 0 V − 10 + 1 µA
MB39A136
DS04-27262-2E 9
(Ta = + 25 °C, VCC pin = 15 V, CTL pin = 5 V, VREF pin = 0 A, VB pin = 0 A)
(Continued)
Parameter Symbol Pin
No. Conditions Value Unit
Min Typ Max
Output Block
[DRV]
High-side
output
on-resistance
RON_MH 23, 15 DRVH1, DRVH2 pins =
− 100 mA ⎯47Ω
RON_ML 23, 15 DRVH1, DRVH2 pins =
100 mA ⎯1.0 3.5 Ω
Low-side
output
on-resistance
RON_SH 21, 17 DRVL1, DRVL2 pins =
− 100 mA ⎯47Ω
RON_SL 21, 17 DRVL1, DRVL2 pins =
100 mA ⎯0.75 1.70 Ω
Output source
current ISOURCE 23, 15,
21, 17
LX1, LX2 pins = 0 V,
CB1, CB2 pins = 5 V
DRVH1, DRVH2 pins,
DRVL1, DRVL2 pins = 2.5 V
Duty ≤ 5%
⎯ − 0.5* ⎯A
Output sink
current ISINK
23, 15
LX1, LX2 pins = 0 V,
CB1, CB2 pins = 5 V
DRVH1, DRVH2 pins = 2.5 V
Duty ≤ 5%
⎯0.9* ⎯A
21, 17
LX1, LX2 pins = 0 V,
CB1, CB2 pins = 5 V
DRVL1, DRVL2 pins = 2.5 V
Duty ≤ 5%
⎯1.2* ⎯A
Minimum on
time tON 23, 15 COMP1, COMP2 pins = 1 V ⎯250* ⎯ns
Maximum
on-duty DMAX 23, 15 FB1, FB2 pins = 0 V 72 80 ⎯%
Dead time tD23, 21,
15, 17
LX1, LX2 pins = 0 V,
CB1, CB2 pins = 5 V ⎯60 ⎯ns
Level
Converter
Block
[LVCNV]
Maximum
current sense
voltage
VRANGE 22, 16 VCC pin − LX1, LX2 pins ⎯220* ⎯mV
Voltage
conversion
gain
ALV 22, 16 ⎯5.4 6.8 8.2 V/V
Offset voltage
at voltage
conversion
VIO 22, 16 ⎯⎯300 ⎯mV
Slope
compensation
inclination
SLOPE 22, 16 ⎯⎯2* ⎯V/V
LX pin
input current ILX 22, 16 LX1, LX2 pins = VCC pin 320 420 600 µA
MB39A136
10 DS04-27262-2E
(Continued)
(Ta = + 25 °C, VCC pin = 15 V, CTL pin = 5 V, VREF pin = 0 A, VB pin = 0 A)
* : This value is not be specified. This should be used as a reference to support designing the circuits.
Parameter Symbol Pin
No. Conditions Value Unit
Min Typ Max
Control Block
[CTL1, CTL2]
ON condition VON 1, 8 CTL1, CTL2 pins 2 ⎯25 V
OFF condition VOFF 1, 8 CTL1, CTL2 pins 0 ⎯0.8 V
Hysteresis
width VH1, 8 CTL1, CTL2 pins ⎯0.4* ⎯V
Input current ICTLH 1, 8 CTL1, CTL2 pins = 5 V ⎯25 40 µA
ICTLL 1, 8 CTL1, CTL2 pins = 0 V ⎯01µA
General
Standby
current ICCS 20 CTL1, CTL2 pins = 0 V ⎯010µA
Power-supply
current ICC 20
LX1, LX2 pins = 0 V,
FB1, FB2 pins = 1.0 V,
MODE pin = VREF pin
⎯3.3 4.7 mA
MB39A136
DS04-27262-2E 11
■TYPICAL CHARACTERISTICS
• Typical data
(Continued)
Power dissipation
Power dissipation vs. Operating ambient temperature
Power dissipation PD (mW)
Operating ambient temperature Ta ( °C)
0
200
400
600
800
1000
1200
1400
1600
1800
2000
−50 −25 0 +25 +50 +75 +100 +125
1644
VREF bias voltage vs.
Operating ambient temperature
Error Amp threshold voltage vs.
Operating ambient temperature
VREF bias voltage VVREF (V)
Error Amp threshold voltage EVTH (V)
Operating ambient temperature Ta ( °C) Operating ambient temperature Ta ( °C)
3.24
3.26
3.28
3.3
3.32
3.34
3.36
-40 -20 0 +20 +40 +60 +80 +100
VCC = 15 V
fosc = 500 kHz
-40 -20 0 +20 +40 +60 +80 +100
0.69
0.695
0.7
0.705
0.71
CH1
CH2
VCC = 15 V
fosc = 500 kHz
MB39A136
12 DS04-27262-2E
(Continued)
Oscillation frequency vs.
Operating ambient temperature
Dead time vs.
Operating ambient temperature
Oscillation frequency fOSC (kHz)
Dead time tD (ns)
Operating ambient temperature Ta ( °C) Operating ambient temperature Ta( °C)
tD1 : period from DRVL off to DRVH on
tD2 : period from DRVH off to DRVL on
Oscillation frequency vs. Timing resistor value VB bias voltage vs. VB bias output current
Oscillation frequency fOSC (kHz)
VB bias voltage VVB (V)
Timing resistor value RRT (kΩ) VB bias output current IVB (A)
Maximum duty cycle vs.
Power supply voltage
Maximum duty cycle vs.
Operating ambient temperature
Maximum duty cycle DMAX (%)
Maximum duty cycle DMAX (%)
Power supply voltage VVCC (V) Operating ambient temperature Ta ( °C)
-40 -20 0 +20 +40 +60 +80 +100
475
480
485
490
495
500
505
VCC = 15 V
-40 -20 0 +20 +40 +60 +80+100
30
40
50
60
70
80
90
VCC = 15 V
fosc = 500 kHz
tD2
tD1
VCC = 15 V
Ta = + 25°C
1000
100
10 100 1000
fosc = 500 kHz
Ta = + 25°C
-0.025 -0.02
VCC = 6 V
VCC = 5 V
VCC = 4.5 V
-0.01-0.015 -0.005 0
5.5
6
5
4.5
4
3.5
3
2.5
2
fosc = 500 kHz
Ta = + 25°C
CH2
CH1
80
79
78
77
76
75 0102030-40 -20 0 +20 +40 +60 +80 +100
75
76
77
78
79
80
VCC = 15 V
fosc = 500 kHz
CH2
CH1
MB39A136
DS04-27262-2E 13
■FUNCTION DESCRIPTION
1. Current Mode
It uses the current waveform from the switching (Q1) as a control waveform to control the output voltage, as
described below:
1 : The clock (CK) from the internal clock generator (OSC) sets RS-FF and turns on the high-side FET.
2 : Turning on the high-side FET causes the inductor current (IL) rise. Generate Vs that converts this current
into the voltage.
3 : The current comparator (I Comp.) compares this Vs with the output (COMP) from the error amplifier (Error
Amp) that is negative-feedback from the output voltage (Vo).
4 : When I Comp. detects that Vs exceeds COMP, it resets RS-FF and turns off high-side FET.
5 : The clock (CK) from the clock generator (OSC) turns on the high-side FET again.
Thus, switching is repeated.
Operate so that the FB electrical potential may become INTREF electrical potential, and stabilize the output
voltage as a feedback control.
INTREF
VIN
IL VO
Vs
FB
COMP
RS-FF
<I Comp.>
Rs
<Error Amp>
CK
DRVH
DRVL
OSC
Drive
Logic
R
SQCurrent
Sense
−
+
−
+
Q1
Q2
t
on
COMP
t
off
Vs
IL
OSC(CK)
DRVH
1
2
3
45
MB39A136
14 DS04-27262-2E
(1) Reference Voltage Block (REF)
The reference voltage circuit (REF) generates a temperature-compensated reference voltage (3.3 [V] Typ) using
the voltage supplied from the VCC pin. The voltage is used as the reference voltage for the IC's internal circuit.
The reference voltage can be used to supply a load current of up to 100 µA to an external device through the
VREF pin.
(2) Bias Voltage Block (VB Reg.)
Bias Voltage Block (VB Reg.) generates the reference voltage used for IC’s internal circuit, using the voltage
supplied from the VCC pin. The reference voltage is a temperature-compensated stable voltage (5 [V] Typ) to
supply a current of up to 100 mA through the VB pin.
(3) Under Voltage Lockout Protection Circuit Block (UVLO)
The circuit protects against IC malfunction and system destruction/deterioration in a transitional state or a
momentary drop when a bias voltage (VB) or an internal reference voltage (VREF) starts. It detects a voltage
drop at the VB pin or the VREF pin and stops IC operation. When voltages at the VB pin and the VREF pin
exceed the threshold voltage of the under voltage lockout protection circuit, the system is restored.
(4) Soft-start/Soft-stop Block (Soft-Start, Soft-Stop)
Soft-start
It protects a rush current or an output voltage (VOx) from overshooting at the output start. Since the lamp voltage
generated by charging the capacitor connecting to the CSx pin is used for the reference voltage of the error
amplifier (Error Amp), it can set the soft-start time independent of a load of the output (VOx). When the IC starts
with “H” level of the CTLx pin, the capacitor at the CSx pin (CS) starts to be charged at 5.5 µA. The output
voltage (VOx) during the soft-start period rises in proportion to the voltage at the CSx pin generated by charging
the capacitor at the CSx pin.
During the soft-start with 0.8 V > voltage at CS1 and CS2 pins, operations are as follows:
• Fixed PWM operation only (fixed PWM even if MODE pin is set to “L”)
• Over-voltage protection function and under-voltage protection function are invalid.
Soft-stop
It discharges electrical charges stored in a smoothing capacitor at output stop. Setting the CTLx pin to “L” level
starts the soft-stop function independent of a load of output (Vox). Since the capacitor connecting to the CSx
pin starts to discharge through the IC-built-in soft-stop discharging resistance (70 [kΩ] Typ) when the CTLx pin
sets at “L” level enters its lamp voltage into the error amplifier (Error Amp), the soft-stop time can be set
independent of a load of output (VOx). When discharging causes the voltage at the CSx pin to drop below 100
mV (Typ), the IC shuts down and changes to the stand-by state. In addition, the soft-stop function operates after
the under-voltage protection circuit block (UVP Comp.) is latched or after the over-temperature protection circuit
block (OTP) detects over-temperature.
During the soft-stop with, 0.8 V > voltage at CS1 and CS2 pins, operations are as follows:
• Fixed PWM operation only (fixed PWM even if MODE pin is set to “L”)
• Over-voltage protection function and under-voltage protection function are invalid.
MB39A136
DS04-27262-2E 15
(5) Clock Generator Block (OSC)
The clock generator has the built-in oscillation frequency setting capacitor and generates a clock that 180°phase
shifted from each channel by connecting the oscillation frequency setting resistor to the RT pin (Symmetrical-
Phase method).
(6-1) Error Amp Block (Error Amp1, Error Amp2)
The error amplifiers (Error Amp1 and Error Amp2) detect the output voltage from the DC/DC converter and
output to the current comparators (I Comp.1 and I Comp.2). The output voltage setting resistor externally con-
nected to FB1 and FB2 pins allows an arbitrary output voltage to be set.
In addition, since an external resistor and an external capacitor serially connected between COMP1 and FB1
pins and between COMP2 and FB2 pins allow an arbitrary loop gain to be set, it is possible for the system to
compensate a phase stably.
(6-2) Over Current Detection (Protection) Block (ILIM)
It is the current detection circuit to restrict an output current (IOX). The over current detection block (ILIM) compares
an output waveform of the level converter of each channel (see “(12) Level Converter Block (LVCNV)”) with the
ILIMx pin voltage in every cycle. As a load resistance (ROX) drops, a load current (IOX) increases. Therefore, the
output waveform of the level converter exceeds the ILIM pin voltage of each channel. At this time, the output
current can be restricted by turning off FET on the high-side and suppressing a peak value of the inductor current.
As a result, the output voltage (VOX) should drop.
Furthermore, if the output voltage drops and the electrical potential at the FBx pin drops below 0.3 V, the oscillation
frequency (fOSC) drops to 1/8.
(7) Over-voltage Protection Circuit Block (OVP Comp.)
The circuit protects a device connecting to the output when the output voltage (VOx) rises.
It compares 1.15 times (Typ) of the internal reference voltage (INTREF) (0.7 V) that is non-inverting-entered into
the error amplifier with the feedback voltage that is inverting-entered into the error amplifier and if it detects the
state where the latter is higher than the former by 50 µs (Typ). It stops the voltage output by setting the RS latch,
setting the DRVHx pin to “L” level, setting the DRVLx pin to “H” level, turning off the high-side FETs, and turning
on the low-side FETs.
The conditions below cancel the protection function:
• Setting CTL1 and CTL2 to “L”.
• Setting the power supply voltage below the UVLO threshold voltage (VTHL1 and VTHL2).
(8) Under-voltage Protection Circuit Block (UVP Comp.)
It protects a device connecting to the output by stopping the output when the output voltage (VOX) drops.
It compares 0.7 times (Typ) of the internal reference voltage (INTREF) (0.7 V) that is non-inverting-entered into
the error amplifier with the feedback voltage that is inverting-entered into the error amplifier and if it detects the
state where the latter is lower than the former by 512/fosc [s](Typ), it stops the voltage output for both channels
by setting the RS latch.
The conditions below cancel the protection function:
• Setting CTL1 and CTL2 to “L”.
• Setting the power supply voltage below the UVLO threshold voltage (VTHL1 and VTHL2).
MB39A136
16 DS04-27262-2E
(9) Over temperature Protection Circuit Block (OTP)
The circuit protects an IC from heat-destruction. If the temperature at the joint part reaches +160 °C, the circuit
stops the voltage output for both channels by discharging the capacitor connecting to the CSx pin through the
soft-stop discharging resistance (70 [kΩ] Typ) in the IC.
In addition, if the temperature at the joint part drops to +135 °C, the output restarts again through the soft-start
function.
Make sure to design the DC/DC power supply system so that the over temperature protection does not start
frequently.
(10) PFM Control Circuit Block (MODE)
It sets the control mode of the IC and makes control at automatic PFM/PWM switching.
Automatic PFM/PWM switching mode operation
It compares the LX1 pin and the LX2 pin voltages with GND electrical potential at Di Comp. In the comparison,
the negative voltage at the LX pin causes the low-side FET to set on, positive voltage causes it to set off (Di
Comp. method) . As a result, the method restricts the back flow of the inductor current at a light load and makes
the switching of the inductor current discontinuous (DCM) . Such an operation allows the oscillation frequency
to drop, resulting in high efficiency at a light load.
(11) Output Block (DRV)
The output circuit is configured in CMOS type for both of the high-side and the low-side, allowing the external
N-ch MOS FET to drive.
(12) Level Converter Block (LVCNV)
The circuit detects and converts the current when the high-side FET turns on. It converts the voltage waveform
between drain side (VCC pin voltage) and the source side (LX1 and LX2 pin voltage) on the high-side FET into
the voltage waveform for GND reference.
Note: x : Each channel number
(13) Control Block (CTL1, CTL2)
The circuit controls on/off of the output from the IC.
Control function table
MODE pin connection Control mode Features
“L” (GND) Automatic PFM/PWM
switching Highly-efficient at light load
“H” (VREF) Fixed PWM
Stable oscillation frequency
Stable switching ripple voltage
Excellent in rapid load change characteristic at heavy
load to light load
CTL1 CTL2 DC/DC converter
(VO1)
DC/DC converter
(VO2) Remarks
L L OFF OFF Standby
H L ON OFF ⎯
LHOFFON⎯
H H ON ON ⎯
MB39A136
DS04-27262-2E 17
■PROTECTION FUNCTION TABLE
The following table shows the state of each pin when each protection function operates.
Note: x is the each channel number
Protection Function Detection
condition
Output of each pin after detection DC/DC output
dropping operation
VREF VB DRVHx DRVLx
Under Voltage Lock Out
Protection
(UVLO)
VB < 3.6 V
VREF < 2.7 V < 2.7 V < 3.6 V L L Self-discharge by load
Under Voltage Protection
(UVP) FBx < 0.49 V 3.3 V 5 V L L Electrical discharge by
soft-stop function
Over Voltage Protection
(OVP) FBx > 0.805 V 3.3 V 5 V L H 0 V clamping
Over Current Protection
(ILIM) COMPx > ILIMx 3.3 V 5V switching switching
The output voltage is
dropping to keep con-
stant output current.
Over Temperature
Protection
(OTP)
Tj > + 160 °C 3.3 V 5 V L L Electrical discharge by
soft-stop function
CONTROL
(CTL)
CTLx : H→L
(CSx > 0.1 V) 3.3 V 5 V L L
MB39A136
18 DS04-27262-2E
■I/O PIN EQUIVALENT CIRCUIT DIAGRAM
(Continued)
VCC
GND
VB
VREF
VB
GND
VCC
GND
CTL1,CTL2
VREF
GND
CS1,CS2
VREF
GND
FB1,FB2
VREF
GND
COMP1,
COMP2
VB pin CS1, CS2 pins
VREF pin CTL1, CTL2 pins
FB1, FB2 pins COMP1, COMP2 pins
ESD protection element
MB39A136
DS04-27262-2E 19
(Continued)
DRVL1,DRVL2
VREF
GND
RT
VREF
GND
LX1,LX2
CB1,CB2
DRVH1,
DRVH2
VB
GND
ILIM1,ILIM2
VREF
GND
MODE
VREF
GND
ILIM1,ILIM2
VREF
GND
VB
VREF
GND
LX1,LX2
CB1,CB2
DRVH1,
DRVH2
MODE pin CB1, CB2, DRVH1, DRVH2, LX1, LX2 pins
ILM1, ILM2 pins RT pin
DRVL1, DRVL2 pins
MB39A136
20 DS04-27262-2E
■EXAMPLE APPLICATION CIRCUIT
VCC
V
IN
(4.5 V to 25 V) MODE
VREF
R21
C13
3
20
FB1
4
COMP1
2
CS1
A
613
C7
R23
C9
R8-1
R8-2
R9
MB39A136
<CH1>
5
ILIM1
R11
R12
11
10
12
CS2
COMP2
FB2
<CH2>
9
ILIM2
C8
C11 R25
R14-1
R14-2
R15
R17
R18
718
GNDVREF
C15
1
15
16
14
17
CB2
DRVH2
DRVL2
LX2
V
O
2
CTL1
CTL2
8
D2
Q2 L2
Q2 C4-1
C4-2
C4-3
C3-1
C3-2
C6
B
23
22
24
21
CB1
DRVH1
DRVL1
LX1
19 VB
V
O
1
A
D2
Q1 L1
Q1 C2-1
C2-2
C2-3
C1
C5
C14
RT
B
MB39A136
DS04-27262-2E 21
■PARTS LI ST
(Continued)
Component Item Specification Vendor Package Parts Name Remark
Q1 N-ch FET
VDS = 30 V,
ID = 8 A,
Ron = 21 mΩ
NEC SO-8 µPA2755 Dual type
(2 elements)
Q2 N-ch FET
VDS = 30 V,
ID = 8 A,
Ron = 21 mΩ
NEC SO-8 µPA2755 Dual type
(2 elements)
D2 Diode VF = 0.35 V
at IF = 0.2 A Onsemi SOT-323 BAT54AWT1 Dual type
L1 Inductor 1.5 µH
(6.2 mΩ, 8.9 A) TDK ⎯VLF10040T-1R5N
L2 Inductor 3.3 µH
(9.7 mΩ, 6.9 A) TDK ⎯VLF10045T-3R3N
C1 Ceramic capacitor 22 µF (25 V) TDK 3225 C3225JC1E226M
C2-1
C2-2
C2-3
Ceramic capacitor
Ceramic capacitor
Ceramic capacitor
22 µF (10 V)
22 µF (10 V)
22 µF (10 V)
TDK
TDK
TDK
3216
3216
3216
C3216JB1A226M
C3216JB1A226M
C3216JB1A226M
3 capacitors in
parallel
C3-1
C3-2
Ceramic capacitor
Ceramic capacitor
22 µF (25 V)
22 µF (25 V)
TDK
TDK
3225
3225
C3225JC1E226M
C3225JC1E226M
2 capacitors in
parallel
C4-1
C4-2
C4-3
Ceramic capacitor
Ceramic capacitor
Ceramic capacitor
22 µF (10 V)
22 µF (10 V)
22 µF (10 V)
TDK
TDK
TDK
3216
3216
3216
C3216JB1A226M
C3216JB1A226M
C3216JB1A226M
3 capacitors in
parallel
C5 Ceramic capacitor 0.1 µF (50 V) TDK 1608 C1608JB1H104K
C6 Ceramic capacitor 0.1 µF (50 V) TDK 1608 C1608JB1H104K
C7 Ceramic capacitor 0.022 µF (50 V) TDK 1608 C1608JB1H223K
C8 Ceramic capacitor 0.022 µF (50 V) TDK 1608 C1608JB1H223K
C9 Ceramic capacitor 820 pF (50 V) TDK 1608 C1608CH1H821J
C11 Ceramic capacitor 1000 pF (50 V) TDK 1608 C1608CH1H102J
C13 Ceramic capacitor 0.01 µF (50 V) TDK 1608 C1608JB1H103K
C14 Ceramic capacitor 2.2 µF (16 V) TDK 1608 C1608JB1C225K
C15 Ceramic capacitor 0.1 µF (50 V) TDK 1608 C1608JB1H104K
R8-1
R8-2 Resistor 1.6 kΩ
9.1 kΩ
SSM
SSM
1608
1608
RR0816P162D
RR0816P912D
2 capacitors in
series
R9 Resistor 15 kΩSSM 1608 RR0816P153D
R11 Resistor 56 kΩSSM 1608 RR0816P563D
R12 Resistor 47 kΩSSM 1608 RR0816P473D
R14-1
R14-2 Resistor 1.8 kΩ
39 kΩ
SSM
SSM
1608
1608
RR0816P182D
RR0816P393D
2 capacitors in
series
R15 Resistor 11 kΩSSM 1608 RR0816P113D
MB39A136
22 DS04-27262-2E
(Continued)
NEC : NEC Electronics Corporation
Onsemi : ON Semiconductor Corporation
TDK : TDK Corporation
SSM : SUSUMU Co., LTD
Component Item Specification Vendor Package Parts Name Remark
R17 Resistor 56 kΩSSM 1608 RR0816P563D
R18 Resistor 56 kΩSSM 1608 RR0816P563D
R21 Resistor 82 kΩSSM 1608 RR0816P823D
R23 Resistor 22 kΩSSM 1608 RR0816P223D
R25 Resistor 56 kΩSSM 1608 RR0816P563D
MB39A136
DS04-27262-2E 23
■APPLICATION NOTE
Setting method for PFM/PWM and fixed PWM modes
For the setting method for each mode, see“■ FUNCTION DESCRIPTION (10) PFM Control Circuit Block
(MODE)”.
Cautions at PFM/PWM mode
If a load current drops rapidly because of rapid load change and others, it tends to take a lot of time to restore
overshooting of an output voltage.
As a result, the over-voltage protection may operate.
In this case, solution are possible by the addition of the load resistance of value to be able to restore the output
voltage in the over-voltage detection time.
Setting method of output voltage
Set it by adjusting the output voltage setting zero-power resistance ratio.
Make sure that the setting does not exceed the maximum on-duty.
Calculate the on-duty by the following formula:
VO = R1 + R2 × 0.7
R2
VO : Output setting voltage [V]
R1, R2 : Output setting resistor value [Ω]
DMAX_Min = VO + RON_Sync × IOMAX
VIN − RON_Main × IOMAX + RON_Sync × IOMAX
DMAX_Min : Minimum value of the maximum on-duty cycle
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
RON_Main : High-side FET ON resistance [Ω]
RON_Sync : Low-side FET ON resistance [Ω]
IOMAX : Maximum load current[A]
R1
V
O
R2
FB1
FB2
MB39A136
24 DS04-27262-2E
Oscillation frequency setting method
Set it by adjusting the RT pin resistor value.
The oscillation frequency must set for on-time (tON) to become 300ns or more.
Calculate the on-time by the following formula.
fOSC = 1.09
RRT × 40 × 10 − 12 + 300 × 10 − 9
RRT : RT resistor value [Ω]
fOSC : Oscillation frequency [Hz]
tON = VO
VIN × fOSC
tON : On-time [s]
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
MB39A136
DS04-27262-2E 25
Setting method of soft-start time
Calculate the soft-start time by the following formula.
tS = 1.4 × 105 × CCS
Calculate delay time until the soft-start beginning by the following formula.
td1 = 30 × CVB + 290 × CVREF + 1.455 × 104 × CCS
Calculate delay time for starting while one channel has already started (UVLO released : VB, VREF output
before) by the following formula.
td2 = 1.455 × 104 × CCS
Calculate the discharge time at the soft-stop by the following formula.
tdis = 1.44 × 105 × CCS
In addition, calculate the delay time to the discharge starting by the following formula.
td3 = 7.87 × 104 × CCS
ts : Soft-start time[s] (Time to becoming output 100%)
CCS : CS pin capacitor value [F]
td1 : Delay time including VB voltage and VREF voltage starts [s]
CCS : CS pin capacitor value [F]
CVB : VB pin capacitor value [F]
CVREF : VREF pin capacitor value [F] (0.1 [µF] Typ)
td2 : Delay time for starting while one channel has already started [s]
CCS : CS pin capacitor value [F]
tdis : Discharge time [s]
CCS : CS pin capacitor value [F]
td3 : Delay time until discharge start [s]
CCS : CS pin capacitor value [F]
CTL1
CTL2
V
O
1
V
O
2
ts
t
d1
t
d2
t
dis
t
d3
MB39A136
26 DS04-27262-2E
• Simultaneous operation of plural channels
Soft-start/soft-stop operation according to the same timing as two channels can be achieved by even connecting
it as shown in the figure below at the power supply on/off.
<Connection example 1> When you adjust the soft-start time
Make the CS capacitor common. Connect CTL1 and CTL2.
Note: In this case, the soft-start time (ts), the discharge time (tdis), and the delay time (td1, td2, td3) decrease in
the half value of compared with when CS capacitor is connected to each channel.
CS1
CTL1
MB39A136
CS2
CTL
V
t
< DC/DC 2 >
< DC/DC 1 >
1.8 V
1.2 V
CTL2
Vo
CTL
DC/DC 2 : Vo = 1.8 V setting
DC/DC 1 : Vo = 1.2 V setting
CS
capacitor
MB39A136
DS04-27262-2E 27
Setting method of over current detection value
It is possible to set over-current detection value (ILIM) by adjusting the over-current detection setting resistor value
ratio.
Calculate the over current detection setting resistor value by the following formula.
200 × 103 ≥ R1 + R2 ≥ 30 × 103
* Since the over current detection value depends on the on-resistance of FET, the over current detection setting
resistor value ratio should be adjusted in consideration of the temperature characteristics of the on-resistance.
When the temperature at the FET joint part rises by + 100 °C, the on-resistance of FET increases to about 1.5
times.
* If the over current detection function is not used, connect the ILIM pin (ILIM1 and ILIM2) to the VREF pin.
3.3 × R2 − 0.3
ILIM = R1 + R2 + VIN − VO × (200 × 10 − 9 − VO)
6.8 × RON L2 × fOSC × VIN
ILIM : Over current detection value [A]
R1, R2 : ILIM setting resistor value [Ω]*
L : Inductor value [H]
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
RON : High-side FET ON resistance [Ω]
VREF
ILIM*
R1
R2
I
O
I
LIM
0
Inductor current
Time
Over-current
detection value
MB39A136
28 DS04-27262-2E
Selection of smoothing inductor
The inductor value selects the value that the ripple current peak-to-peak value becomes 50% or less of the
maximum load current as a rough standard. Calculate the inductor value in this case by the following formula.
An inductor ripple current value limited on the principle of operation is necessary for this device. However, when
it uses the high-side FET of the low Ron resistance, the switching ripple voltage become small, and the inductor
ripple current value may become insufficient. This should be solved by the oscillation frequency or reducing the
inductor value.
Select the one of the inductor value that meets a requirement listed below.
It is necessary to calculate the maximum current value that flows to the inductor to judge whether the electric
current that flows to the inductor is a rated value or less. Calculate the maximum current value of the inductor
by the following formula.
L ≥ VIN − VO × VO
LOR × IOMAX VIN × fOSC
L : Inductor value [H]
IOMAX : Maximum load current [A]
LOR : Ripple current peak-to-peak value of Maximum load current ratio (=0.5)
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
L ≤ VIN − VO × VO × RON
∆VRON VIN × fOSC
L : Inductor value [H]
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
∆VRON : Ripple voltage [V] (20 mV or more is recommended)
RON : High-side FET ON resistance [Ω]
ILMAX ≥ IoMAX + ∆IL , ∆IL = VIN − VO × VO
2LVIN × fOSC
ILMAX : Maximum current value of inductor [A]
IoMAX : Maximum load current [A]
∆IL : Ripple current peak-to-peak value of inductor [A]
L : Inductor value [H]
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
∆IL
Io
MAX
IL
MAX
0
Inductor current
t
MB39A136
DS04-27262-2E 29
Selection of SWFET
The switching ripple voltage generated between drain and sources on high-side FET is necessary for this device
operation. Select the one of the SWFET of on-resistance that satisfies the following formula.
Select FET ratings with a margin enough for the input voltage and the load current. Ratings with the over-current
detection setting value or more are recommended.
Calculate a necessary rated value of high-side FET and low-side FET by the following formula.
VDS > VIN
VGS > VB
Moreover, it is necessary to calculate the loss of SWFET to judge whether a permissible loss of SWFET is a
rated value or less. Calculate the loss on high-side FET by the following formula.
PMainFET = PRON_Main + PSW_Main
RON_Main ≥ ∆VRON_Main , RON_Main ≤ VRONMAX
∆IL ILIM + ∆IL
2
RON_Main : High-side FET ON resistance [Ω]
∆IL : Ripple current peak-to-peak value of inductor [A]
∆VRON_Main : High-side FET ripple voltage [V] (20mV or more is recommended)
ILIM : Over current detection value [A]
VRONMAX : Maximum current sense voltage [V] (240mV or less is recommended)
ID > IoMAX + ∆IL
2
ID : Rated drain current [A]
IoMAX : Maximum load current [A]
∆IL : Ripple current peak-to-peak value of inductor [A]
VDS : Rated voltage between drain and source [V]
VIN : Power supply voltage of switching system [V]
VGS : Rated voltage between gate and source [V]
VB : VB voltage [V]
PMainFET : High-side FET loss [W]
PRON_Main : High-side FET conduction loss [W]
PSW_Main : High-side FET SW loss [W]
MB39A136
30 DS04-27262-2E
High-side FET conduction loss
High-side FET SW loss
Calculate the Ibtm, the Itop, the tr and the tf simply by the following formula.
PRON_Main = IoMAX2 × VO × RON_Main
VIN
PRON_Main : High-side FET conduction loss [W]
IOMAX : Maximum load current [A]
VIN : Power supply voltage of switching system [V]
VO : Output voltage [V]
RON_Main : High-side FET ON resistance [Ω]
PSW_Main = VIN × fOSC × (Ibtm × tr + Itop × tf)
2
PSW_Main : High-side FET SW loss [W]
VIN : Power supply voltage of switching system [V]
fOSC : Oscillation frequency [Hz]
Ibtm : Ripple current bottom value of inductor [A]
Itop : Ripple current top value of inductor [A]
tr : Turn-on time on high-side FET [s]
tf : Turn-off time on high-side FET[s]
Ibtm = IOMAX − ∆IL
2
Itop = IOMAX + ∆IL
2
tr = Qgd × 4 tf = Qgd × 1
5 − Vgs (on) Vgs (on)
IOMAX : Maximum load current [A]
∆IL : Ripple current peak-to-peak value of inductor [A]
Qgd : Quantity of charge between gate and drain on high-side FET [C]
Vgs (on) : Voltage between gate and source in Qgd on high-side FET [V]
MB39A136
DS04-27262-2E 31
Calculate the loss on low-side FET by the following formula.
* : The transition voltage of the voltage between drain and source on low-side FET is generally small, and the
switching loss is omitted here for the small one as it is possible to disregard it.
The gate drive power of SWFET is supplied by LDO in IC, therefore all SWFET allowable maximum total charge
(QgTotalMax) of 2ch is determined by the following formula.
Selection of fly-back diode
When the conversion efficiency is valued, the improved property of the conversion efficiency is possible by the
addition of the fly-back diode. Thought it is usually unnecessary. The effect is achieved in the condition where
the oscillation frequency is high or output voltage is lower. Select schottky barrier diode (SBD) that the forward
current is as small as possible. In this DC/DC control IC, the period for the electric current flows to fly back diode
is limited to synchronous rectification period (60 ns × 2) because of using the synchronous rectification method.
Therefore, select the one that the electric current of fly back diode doesn't exceed ratings of forward current
surge peak (IFSM).Calculate the forward current surge peak ratings of fly back diode by the following formula.
Calculate ratings of the fly-back diode by the following formula:
VR_Fly > VIN
PSyncFET = PRon_Sync* = IoMAX2 × (1 − VO) × Ron_Sync
VIN
PSyncFET : Low-side FET loss [W]
PRon_Sync : Low-side FET conduction loss [W]
IOMAX : Maximum load current [A]
VIN : Power supply voltage of switching system [V]
VO : Output voltage [V]
Ron_Sync : Low-side FET on-resistance [Ω]
QgTotalMax ≤ 0.095
fOSC
QgTotalMax : SWFET allowable maximum total charge [C]
fOSC : Oscillation frequency [Hz]
IFSM ≥ IoMAX + ∆IL
2
IFSM : Forward current surge peak ratings of fly back diode [A]
IoMAX : Maximum load current [A]
∆IL : Ripple current peak-to-peak value of inductor [A]
VR_Fly : Reverse voltage of fly-back diode direct current [V]
VIN : Power supply voltage of switching system [V]
MB39A136
32 DS04-27262-2E
Selection of output capacitor
This device supports a small ceramic capacitor of the ESR. The ceramic capacitor that is low ESR is an ideal
to reduce the ripple voltage compared with other capacitor. Use the tantalum capacitor and the polymer capacitor
of the low ESR when a mass capacitor is needed as the ceramic capacitor can not support. To the output voltage,
the ripple voltage by the switching operation of DC/DC is generated. Discuss the lower bound of output capacitor
value according to an allowable ripple voltage. Calculate the output ripple voltage from the following formula.
Notes: • The ripple voltage can be reduced by raising the oscillation frequency and the inductor value besides
capacitor.
• Capacitor has frequency characteristic, the temperature characteristic, and the electrode bias character-
istic, etc. The effective capacitor value might become extremely small depending on the condition. Note
the effective capacitor value in the condition.
Calculate ratings of the output capacitor by the following formula:
VCO > VO
Note: Select the capacitor rating with withstand voltage allowing a margin enough for the output voltage.
In addition, use the allowable ripple current with an enough margin, if it has a rating.
Calculate an allowable ripple current of the output capacitor by the following formula:
∆VO = ( 1 + ESR) × ∆IL
2π × fOSC × CO
∆VO : Switching ripple voltage [V]
ESR : Series resistance component of output capacitor [Ω]
∆IL : Ripple current peak-to-peak value of inductor [A]
CO : Output capacitor value [F]
fOSC : Oscillation frequency [Hz]
VCO : Withstand voltage of the output capacitor [V]
VO : Output voltage [V]
Irms ≥ ∆IL
2√3
Irms : Allowable ripple current (effective value) [A]
∆IL : Ripple current peak-to-peak value of inductor [A]
MB39A136
DS04-27262-2E 33
Selection of input capacitor
Select the input capacitor whose ESR is as small as possible. The ceramic capacitor is an ideal. Use the tantalum
capacitor and the polymer capacitor of the low ESR when a mass capacitor is needed as the ceramic capacitor
can not support. To the power supply voltage, the ripple voltage by the switching operation of DC/DC is generated.
Discuss the lower bound of input capacitor according to an allowable ripple voltage. Calculate the ripple voltage
of the power supply from the following formula.
Notes: • The ripple voltage of the power supply can be reduced by raising the oscillation frequency besides capac-
itor.
• Capacitor has frequency characteristic, the temperature characteristic, and the electrode bias character-
istic, etc. The effective capacitor value might become extremely small depending on the condition. Note
the effective capacitor value in the condition.
Calculate ratings of the input capacitor by the following formula:
VCIN > VIN
Note: Select the capacitor rating with withstand voltage with margin enough for the input voltage.
In addition, use the allowable ripple current with an enough margin, if it has a rating.
Calculate an allowable ripple current by the following formula:
∆VIN = IOMAX × VO + ESR × (IOMAX + ∆IL )
CIN VIN × fOSC 2
∆VIN : Switching system power supply ripple voltage peak-to-peak value [V]
IOMAX : Maximum load current value [A]
CIN : Input capacitor value [F]
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
ESR : Series resistance component of input capacitor [Ω]
∆IL : Ripple current peak-to-peak value of inductor [A]
VCIN : Withstand voltage of the input capacitor [V]
VIN : Power supply voltage of switching system [V]
Irms ≥ IOMAX × √VO × (VIN − VO)
VIN
Irms : Allowable ripple current (effective value) [A]
IOMAX : Maximum load current value [A]
VIN : Power supply voltage of switching system [V]
VO : Output voltage [V]
MB39A136
34 DS04-27262-2E
Selection of boot strap diode
Select Schottky barrier diode (SBD), that forward current is as small as possible. The electric current that drives
the gate of high-side FET flows to SBD of the bootstrap circuit. Calculate the mean current by the following
formula. Select it so as not to exceed the electric current ratings.
ID ≥ Qg × fOSC
Calculate ratings of the boot strap diode by the following formula:
VR_BOOT > VIN
Selection of boot strap capacitor
To drive the gate of high-side FET, the bootstrap capacitor must have enough stored charge. Therefore, a
minimum value as a target is assumed the capacitor which can store electric charge 10 times that of the Qg on
high-side FET. And select the boot strap capacitor.
Calculate ratings of the boot strap capacitor by the following formula:
VCBOOT > VB
ID : Forward current [A]
Qg : Total quantity of charge of gate on high-side FET [C]
fOSC : Oscillation frequency [Hz]
VR_BOOT : Reverse voltage of boot strap diode direct current [V]
VIN : Power supply voltage of switching system [V]
CBOOT ≥ 10 × Qg
VB
CBOOT : Boot strap capacitor [F]
Qg : Amount of gate charge on high-side FET [C]
VB : VB voltage [V]
VCBOOT : Withstand voltage of the boot strap capacitor [V]
VB : VB voltage [V]
MB39A136
DS04-27262-2E 35
Design of phase compensation circuit
Assume the phase compensation circuit of 1pole-1zero to be a standard in this device.
1pole-1zero phase compensation circuit
As for crossover frequency (fCO) that shows the band width of the control loop of DC/DC. The higher it is, the
more excellent the rapid response becomes, however, the possibility of causing the oscillation due to phase
margin shortage increases. Though this crossover frequency (fCO) can be arbitrarily set, make 1/10 of the
oscillation frequencies (fosc) a standard, and set it to the upper limit. Moreover, set the phase margin at least
to 30 °C, and 45 °C or more if possible as a reference.
Set the constants of Rc and Cc of the phase compensation circuit using the following formula as a target.
RC = (VIN − VO) ALVCNV × RON_Main × fCO × 2π × CO × VO × R1
VIN × fOSC × L × IOMAX
CC = CO × VO
RC × IOMAX
RC : Phase compensation resistor value [Ω]
CC : Phase compensation capacitor value [F]
VIN : Power supply voltage of switching system [V]
VO : Output setting voltage [V]
fOSC : Oscillation frequency [Hz]
IOMAX : Maximum load current value [A]
L : Inductor value [H]
CO : Output capacitor value [F]
RON_Main : High-side FET ON resistance[Ω]
R1 : Output setting resistor value [Ω]
ALVCNV : Level converter voltage gain [V/V]
On-duty ≤ 50%: ALVCNV = 6.8
On-duty > 50%: ALVCNV = 13.6
fCO : Cross-over frequency (arbitrary setting) [Hz]
INTREF
V
O
COMP
R1
R2
Rc Cc
FB
Error
Amp
-
+To I Comp.
MB39A136
36 DS04-27262-2E
VB pin capacitor
2.2 µF is assumed to be a standard, and when Qg of SWFET used is large, it is necessary to adjust it. To drive
the gate of high-side FET, the bootstrap capacitor must have enough stored charge. Therefore, a minimum value
as a target is assumed the capacitor, which can store electric charge 100 times that of the Qg of the SWFET.
And select it.
Calculate ratings of the VB pin capacitor by the following formula:
VCVB > VB
CVB ≥ 100 × Qg
VB
CVB : VB pin capacitor value [F]
Qg : Total amount of gate charge of 2 ch respectively: high-side FET and low-side FET [C]
VB : VB voltage [V]
VCVB : Withstand voltage of the VB pin capacitor [V]
VB : VB voltage [V]
MB39A136
DS04-27262-2E 37
VB regulator
In the condition for which the potential difference between VCC and VB is insufficient, the decrease in the voltage
of VB happens because of power output on-resistance and load current (mean current of all external FET gate
driving current and load current of internal IC) of the VB regulator. Stop the switching operation when the voltage
of VB decreases and it reaches threshold voltage (VTHL1) of the under voltage lockout protection circuit. Therefore,
set oscillation frequency or external FET or I/O potential difference of the VB regulator using the following formula
as a target when you use this IC.
VCC ≥ VB (VTHL1) + (Qg × fOSC + ICC) × RVB
If the I/O potential difference is small, the problem can be solved by connecting the VB pin and the VCC pin.
The conditions of the input voltage range are as follows:
Note that if the I/O potential difference is not enough when used, use the actual machine to check carefully the
operations at the normal operation, start operation, and stop operation. In particular, care is needed when the
input voltage range over 6 V.
VCC : Power supply voltage [V] (VIN)
VB (VTHL1) : Threshold voltage of VB under-voltage lockout protection circuit [V] (3.8 [V] Max )
Qg : Total amount of gate charge of 2 ch respectively: high-side FET and low-side FET [C]
fOSC : Oscillation frequency [Hz]
ICC : Power supply current [A] (4.7 × 10−3[A] := Load current of VB (LDO) )
RVB : VB output on-resistance [Ω] (100 Ω (The reference value at VCC = 4.5 V) )
6.0 V
4.5 V 25 V
(2)
(3)(1)
(1) For 4.5 V < VIN < 6.0 V
→ Connect VB pin to VCC.
(2) When the input voltage range steps over 6.0 V
→ Normal use (VCC to VB not connected)
(3) For 6.0 V ≤ VIN
→ Normal use (VCC to VB not connected)
VIN input voltage ranges:
MB39A136
38 DS04-27262-2E
Power dissipation and the thermal design
As for this IC, considerations of the power dissipation and thermal design are not necessary in most cases
because of its high efficiency. However, they are necessary for the use at the conditions of a high power supply
voltage, a high oscillation frequency, high load, and the high temperature.
Calculate IC internal loss (PIC) by the following formula.
PIC = VCC × (ICC + Qg × fOSC)
Calculate junction temperature (Tj) by the following formula.
Tj = Ta + θja × PIC
PIC : IC internal loss [W]
VCC : Power supply voltage (VIN) [V]
ICC : Power supply current [A] (4.7 [mA] Max)
Qg : All SWFET total quantity of charge for ch 2 [C] (Total with Vgs = 5 V)
fOSC : Oscillation frequency[Hz]
Tj : Junction temperature [ °C] (+150 [ °C] Max)
Ta : Ambient temperature [ °C]
θja : TSSOP-24 Package thermal resistance (76 °C/W)
PIC : IC internal loss [W]
MB39A136
DS04-27262-2E 39
Board layout
Consider the points listed below and do the layout design.
• Provide the ground plane as much as possible on the IC mounted face. Connect bypass capacitor connected
with the VCC and VB pins, and GND pin of the switching system parts with switching system GND (PGND).
Connect other GND connection pins with control system GND (AGND), and separate each GND, and try not
to pass the heavy current path through the control system GND (AGND) as much as possible. In that case,
connect control system GND (AGND) and switching system GND (PGND) right under IC.
• Connect the switching system parts as much as possible on the surface. Avoid the connection through the
through-hole as much as possible.
• As for GND pins of the switching system parts, provide the through hole at the proximal place, and connect it
with GND of internal layer.
• Pay the most attention to the loop composed of input capacitor (CIN), SWFET, and fly-back diode (SBD).
Consider making the current loop as small as possible.
• Place the boot strap capacitor (CBOOT1, CBOOT2) proximal to CBx and LXx pins of IC as much as possible.
• This device monitors the voltage between drain and source on high-side FET as voltage between VCC and
LX pins. Place the input capacitor (CIN) and the high-side FET of each CH proximally as much as possible.
Draw out the wiring to VCC pin from the proximal place to the input capacitor of CH1 and CH2. As for the net
of the LXx pin, draw it out from the proximal place to the source pin on high-side FET. Moreover, a large electric
current flows momentary in the net of the LXx pin. Wire the linewidth of about 0.8mm to be a standard, as
short as possible.
• Large electric current flows momentary in the net of DRVHx and DRVLx pins connected with the gate of
SWFET. Wire the linewidth of about 0.8mm to be a standard, as short as possible.
• By-pass capacitor (CVCC, CVREF, CVB) connected with VREF, VCC, and VB, and the resistor (RRT) connected
with the RT pin should be placed close to the pin as much as possible. Also connect the GND pin of the by-
pass capacitor with GND of internal layer in the proximal through-hole.
• Consider the net connected with RT, FBx, and the COMPx pins to keep away from a Switching system parts
as much as possible because it is sensitive to the noise. Moreover, place the output voltage setting resistor
and the phase compensation circuit element connected with this net close to the IC as much as possible, and
try to make the net as short as possible. In addition, for the internal layer right under the installing part, provide
the control system GND (AGND) of few ripple and few spike noises, or provide the ground plane of the power
supply voltage as much as possible.
Switching system parts : Input capacitor (CIN), SWFET, Fly-back diode (SBD), Inductor (L),
Output capacitor (CO)
Note: x : Each channel number
MB39A136
40 DS04-27262-2E
A
GND
P
GND
P
GND
A
GND
C
BOOT2
C
VB
C
VCC
R
RT
C
VREF
1pin C
BOOT1
C
IN
C
O
SBD (option) SBD (option)
V
IN
C
IN
C
O
PGND
Vo1 Vo2
LL
Layout example of IC Layout example of switching components
Through-hole
AGND and PGND are connected right under IC.
Surface Internal
layer
High-side FET
To the LX1 pin
Low-side FET Low-side FET
High-side FET
To the VCC pin Through-hole
Output voltage
Vo1 feedback
Output voltage
Vo2 feedback
To the LX2
pin
MB39A136
DS04-27262-2E 41
■REFERENCE DATA
(Continued)
CH1 Conversion Efficiency CH2 Conversion Efficiency
Conversion Efficiency vs. Load Current Conversion Efficiency vs. Load Current
Conversion Efficiency η (%)
Conversion Efficiency η(%)
Load Current IO1(A) Load Current IO2 (A)
CH1 Load Regulation CH2 Load Regulation
Output Voltage vs. Load Current Output Voltage vs. Load Current
Output Voltage VO1 (V)
Output Voltage VO2(V)
Load Current IO1(A) Load Current IO2 (A)
0.01 0.1 1 10
60
65
70
75
80
85
90
95
100
CH1
V
IN
= 12 V
V
O
1 = 1.2 V
fosc = 300 kHz
Ta = + 25°C
PFM/PWM
Fixed PWM
0.01 0.1 1 10
CH2
V
IN
= 12 V
V
O
2 = 3.3 V
fosc = 300 kHz
Ta = + 25°C
PFM/PWM
60
65
70
75
80
85
90
95
100
Fixed PWM
012345
V
IN
= 12 V
V
O
1 = 1.2 V
MODE = VREF
fosc = 300 kHz
Ta = + 25°C
1.10
1.12
1.14
1.16
1.18
1.20
1.22
1.24
1.26
1.28
1.30
012345
V
IN
= 12 V
V
O
2 = 3.3 V
MODE = VREF
fosc = 300 kHz
Ta = + 25°C
3.00
3.10
3.20
3.30
3.40
3.50
3.60
MB39A136
42 DS04-27262-2E
(Continued)
3
4
2
1
VO1 : 0.5 V/div
CS1 : 2 V/div
LX1 : 10 V/div
IO1 : 10 A/div
500 µs/div
VO1: 1 V/div
1 ms/div
VO2: 1 V/div
CTL1, 2 : 5 V/div
VO1: 1 V/div
1 ms/div
VO2: 1 V/div
CTL1, 2 : 5 V/div
2 A
0 A
V
O
2 : 200 mV/div (3.3 V offset)
100 µs/div
I
O
2 : 1 A/div
CH1
Load Sudden Change Waveform
CH2
Load Sudden Change Waveform
CTL Startup Waveform CTL Stop Waveform
VIN = 12 V, fOSC = 300 kHz, Ta = + 25 °C, Soft-start setting time = 3.0 ms
VO1 = 1.2 V, IO1 = 5 A (0.24 Ω) , VO2 = 3.3 V, IO2 = 5 A (0.66 Ω)
Normal operation → Over current protection → Under voltage protection operation waveform
Normal operation
VIN = 12 V, VO1 = 1.2 V
IO1 = 0←→2 A, fOSC = 300 kHz, Ta = + 25 °CVIN = 12 V, VO2 = 3.3 V
IO2 = 0←→2 A, fOSC = 300 kHz, Ta = + 25 °C
VIN = 12 V
VO1 = 1.2 V
fOSC = 300 kHz
Ta = + 25 °C
Over current
protection operation
Under voltage
protection operation
2 A
0 A
VO1 : 200 mV/div (1.2 V offset)
100 µs/div
IO1 : 1 A/div
MB39A136
DS04-27262-2E 43
■USAGE PRECAUTION
1. Do not configure the IC over the maximum ratings.
If the IC is used over the maximum ratings, the LSI may be permanently damaged.
It is preferable for the device to be normally operated within the recommended usage conditions. Usage outside
of these conditions can have an adverse effect on the reliability of the LSI.
2. Use the device within the recommended operating conditions.
The recommended values guarantee the normal LSI operation under the recommended operating conditions.
The electrical ratings are guaranteed when the device is used within the recommended operating conditions
and under the conditions stated for each item.
3. Printed circuit board ground lines should be set up with consideration for common imped-
ance.
4. Take appropriate measures against static electricity.
• Containers for semiconductor materials should have anti-static protection or be made of conductive material.
• After mounting, printed circuit boards should be stored and shipped in conductive bags or containers.
• Work platforms, tools, and instruments should be properly grounded.
• Working personnel should be grounded with resistance of 250 kΩ to 1 MΩ in series between body and ground.
5. Do not apply negative voltages.
The use of negative voltages below − 0.3 V may make the parasitic transistor activated, and can cause mal-
functions.
■ORDERING INFORMATION
■EV BOARD ORDERING INFORMATION
■RoHS COMPLIANCE INFORMATION OF LEAD (Pb) FREE VERSION
The LSI products of Fujitsu Microelectronics with “E1” are compliant with RoHS Directive, and has observed the
standard of lead, cadmium, mercury, Hexavalent chromium, polybrominated biphenyls (PBB), and polybromi-
nated diphenyl ethers (PBDE). A product whose part number has trailing characters “E1” is RoHS compliant.
Part number Package Remarks
MB39A136PFT-❏❏❏E1 24-pin plastic TSSOP
(FPT-24P-M09) Lead Free version
Part number EV board version No. Remarks
MB39A136EVB-01 MB39A136EVB-01 Rev2.0 TSSOP-24
MB39A136
44 DS04-27262-2E
■MARKING FORMAT (Lead Free version)
XXXX
39A136
XXX
E1
INDEX
Lead Free version
MB39A136
DS04-27262-2E 45
■LABELING SAMPLE (Lead free version)
2006/03/01
ASSEMBLED IN JAPAN
G
QC PASS
(3N) 1MB123456P-789-GE1
1000
(3N)2 1561190005 107210
1,000
PCS
0605 - Z01A
1000
1/1
1561190005
MB123456P - 789 - GE1
MB123456P - 789 - GE1
MB123456P - 789 - GE1
Pb
Lead free mark
JEITA logo JEDEC logo
The part number of a lead-free product has the
trailing characters “E1”.
MB39A136
46 DS04-27262-2E
■MB39A136PFT-❏❏❏ E1
RECOMMENDED CONDITIONS OF MOISTURE SENSITIVITY LEVEL
[Fujitsu Microelectronics Recommended Mounting Conditions]
[Mounting Conditions]
(1) IR (infrared reflow)
(2) Manual soldering (partial heating method)
Temperature at the tip of an soldering iron: 400 °C max
Time: Five seconds or below per pin
Item Condition
Mounting Method IR (infrared reflow) , Manual soldering (partial heating method)
Mounting times 2 times
Storage period
Before opening Please use it within two years after
Manufacture.
From opening to the 2nd
reflow Less than 8 days
When the storage period after
opening was exceeded
Please process within 8 days
after baking (125 °C, 24h)
Storage conditions 5 °C to 30 °C, 70%RH or less (the lowest possible humidity)
260°C
(e)
(d')
(d)
255°C
170 °C
190 °C
RT (b)
(a)
(c)
to
Note: Temperature : on the top of the package body
“H” level : 260 °C Max
(a) Temperature increase gradient : Average 1 °C/s to 4 °C/s
(b) Preliminary heating : Temperature 170 °C to 190 °C, 60 s to 180 s
(c) Temperature increase gradient : Average 1 °C/s to 4 °C/s
(d) Peak temperature : Temperature 260 °C Max; 255 °C or more, 10 s or less
(d’) Main heating : Temperature 230 °C or more, 40 s or less
or
Temperature 225 °C or more, 60 s or less
or
Temperature 220 °C or more, 80 s or less
(e) Cooling : Natural cooling or forced cooling
Main heating
MB39A136
DS04-27262-2E 47
■PACKAGE DIMENSIONS
Please confirm the latest Package dimension by following URL.
http://edevice.fujitsu.com/package/en-search/
24-pin plastic TSSOP Lead pitch 0.50 mm
Package width
×
package length
4.40 mm × 6.50 mm
Lead shape Gullwing
Sealing method Plastic mold
Mounting height 1.20 mm MAX
Weight 0.08 g
24-pin plastic TSSOP
(FPT-24P-M09)
(FPT-24P-M09)
C
2007-2008 FUJITSU MICROELECTRONICS LIMITED F24032S-c-2-3
6.50±0.10(.256±.004)
#
4.40±0.10 6.40±0.20
(.252±.008)
(.173±.004)
#
0.10±0.05
(Mounting height)
0.10(.004)
0.50(.020)
1 12
24 13
"A"
(Stand off)
0.145±0.045
(.0057±.0018)
M
0.13(.005)
Details of "A" part
0~8˚
(.024±.006)
0.60±0.15
INDEX
(.004±.002)
BTM E-MARK
1.10 +0.10
+.004
–0.15
–.006
.043
0.20 +0.07
+.003
–0.02
–.001.008
Dimensions in mm (inches).
Note: The values in parentheses are reference values.
Note 1) Pins width and pins thickness include plating thickness.
Note 2) Pins width and pins thickness include plating thickness.
Note 3) #: These dimensions do not include resin protrusion.
MB39A136
48 DS04-27262-2E
■CONTENTS
page
-DESCRIPTION .................................................................................................................................................... 1
-FEATURES .......................................................................................................................................................... 1
-APPLICATION ..................................................................................................................................................... 1
-PIN ASSIGNMENT ............................................................................................................................................. 2
-PIN DESCRIPTION ............................................................................................................................................ 3
-BLOCK DIAGRAM .............................................................................................................................................. 4
-ABSOLUTE MAXIMUM RATINGS ................................................................................................................... 5
-RECOMMENDED OPERATING CONDITIONS ............................................................................................ 6
-ELECTRICAL CHARACTERISTICS ................................................................................................................ 7
-TYPICAL CHARACTERISTICS ........................................................................................................................ 11
-FUNCTION DESCRIPTION .............................................................................................................................. 13
-PROTECTION FUNCTION TABLE .................................................................................................................. 17
-I/O PIN EQUIVALENT CIRCUIT DIAGRAM ................................................................................................... 18
-EXAMPLE APPLICATION CIRCUIT ................................................................................................................ 20
-PARTS LIST ......................................................................................................................................................... 21
-APPLICATION NOTE ......................................................................................................................................... 23
-REFERENCE DATA ........................................................................................................................................... 41
-USAGE PRECAUTION ...................................................................................................................................... 43
-ORDERING INFORMATION ............................................................................................................................. 43
-EV BOARD ORDERING INFORMATION ....................................................................................................... 43
-RoHS COMPLIANCE INFORMATION OF LEAD (Pb) FREE VERSION ................................................... 43
-MARKING FORMAT (Lead Free version) ....................................................................................................... 44
-LABELING SAMPLE (Lead free version) ........................................................................................................ 45
-MB39A136PFT-❏❏❏ E1 RECOMMENDED CONDITIONS OF MOISTURE SENSITIVITY LEVEL .... 46
-PACKAGE DIMENSIONS .................................................................................................................................. 47
MB39A136
DS04-27262-2E 49
MEMO
MB39A136
50 DS04-27262-2E
MEMO
MB39A136
DS04-27262-2E 51
MEMO
MB39A136
FUJITSU MICROELECTRONICS LIMITED
Shinjuku Dai-Ichi Seimei Bldg., 7-1, Nishishinjuku 2-chome,
Shinjuku-ku, Tokyo 163-0722, Japan
Tel: +81-3-5322-3347 Fax: +81-3-5322-3387
http://jp.fujitsu.com/fml/en/
For further information please contact:
North and South America
FUJITSU MICROELECTRONICS AMERICA, INC.
1250 E. Arques Avenue, M/S 333
Sunnyvale, CA 94085-5401, U.S.A.
Tel: +1-408-737-5600 Fax: +1-408-737-5999
http://www.fma.fujitsu.com/
Europe
FUJITSU MICROELECTRONICS EUROPE GmbH
Pittlerstrasse 47, 63225 Langen, Germany
Tel: +49-6103-690-0 Fax: +49-6103-690-122
http://emea.fujitsu.com/microelectronics/
Korea
FUJITSU MICROELECTRONICS KOREA LTD.
206 Kosmo Tower Building, 1002 Daechi-Dong,
Gangnam-Gu, Seoul 135-280, Republic of Korea
Tel: +82-2-3484-7100 Fax: +82-2-3484-7111
http://kr.fujitsu.com/fmk/
Asia Pacific
FUJITSU MICROELECTRONICS ASIA PTE. LTD.
151 Lorong Chuan,
#05-08 New Tech Park 556741 Singapore
Tel : +65-6281-0770 Fax : +65-6281-0220
http://www.fmal.fujitsu.com/
FUJITSU MICROELECTRONICS SHANGHAI CO., LTD.
Rm. 3102, Bund Center, No.222 Yan An Road (E),
Shanghai 200002, China
Tel : +86-21-6146-3688 Fax : +86-21-6335-1605
http://cn.fujitsu.com/fmc/
FUJITSU MICROELECTRONICS PACIFIC ASIA LTD.
10/F., World Commerce Centre, 11 Canton Road,
Tsimshatsui, Kowloon, Hong Kong
Tel : +852-2377-0226 Fax : +852-2376-3269
http://cn.fujitsu.com/fmc/en/
Specifications are subject to change without notice. For further information please contact each office.
All Rights Reserved.
The contents of this document are subject to change without notice.
Customers are advised to consult with sales representatives before ordering.
The information, such as descriptions of function and application circuit examples, in this document are presented solely for the purpose
of reference to show examples of operations and uses of FUJITSU MICROELECTRONICS device; FUJITSU MICROELECTRONICS
does not warrant proper operation of the device with respect to use based on such information. When you develop equipment incorporating
the device based on such information, you must assume any responsibility arising out of such use of the information.
FUJITSU MICROELECTRONICS assumes no liability for any damages whatsoever arising out of the use of the information.
Any information in this document, including descriptions of function and schematic diagrams, shall not be construed as license of the use
or exercise of any intellectual property right, such as patent right or copyright, or any other right of FUJITSU MICROELECTRONICS
or any third party or does FUJITSU MICROELECTRONICS warrant non-infringement of any third-party's intellectual property right or
other right by using such information. FUJITSU MICROELECTRONICS assumes no liability for any infringement of the intellectual
property rights or other rights of third parties which would result from the use of information contained herein.
The products described in this document are designed, developed and manufactured as contemplated for general use, including without
limitation, ordinary industrial use, general office use, personal use, and household use, but are not designed, developed and manufactured
as contemplated (1) for use accompanying fatal risks or dangers that, unless extremely high safety is secured, could have a serious effect to
the public, and could lead directly to death, personal injury, severe physical damage or other loss (i.e., nuclear reaction control in nuclear
facility, aircraft flight control, air traffic control, mass transport control, medical life support system, missile launch control in weapon
system), or (2) for use requiring extremely high reliability (i.e., submersible repeater and artificial satellite).
Please note that FUJITSU MICROELECTRONICS will not be liable against you and/or any third party for any claims or damages arising
in connection with above-mentioned uses of the products.
Any semiconductor devices have an inherent chance of failure. You must protect against injury, damage or loss from such failures by
incorporating safety design measures into your facility and equipment such as redundancy, fire protection, and prevention of over-current
levels and other abnormal operating conditions.
Exportation/release of any products described in this document may require necessary procedures in accordance with the regulations of
the Foreign Exchange and Foreign Trade Control Law of Japan and/or US export control laws.
The company names and brand names herein are the trademarks or registered trademarks of their respective owners.
Edited: Sales Promotion Department
