DS04-27601-2E
FUJITSU SEMICONDUCTOR
DATA SHEET
ASSP For Power Supply Applications
Power Management Switch
MB3802
■DESCRIPTION
The MB3802 is a power management switch incorporating two s witch circuits with extremely lo w ON resistance.
NO diode is required because the switch block is configured with an N-ch MOS to prevent reverse current at
switch OFF.
The MB3802 starts at a very low v oltage (typical VIN > 2.2V) and a stab le ON resistance is obtained irrespective
of the switching voltage because the internal DC/DC converter applies the optimum voltage for the N-ch MOS
gate at switch ON.
Moreover, the load-side capacitor is discharged at switch OFF, and the powe r supply for various power supply
systems is switched efficiently.
■FEATURES
• Extremely low ON resistance:
RON = 0.12 Ω (typical)
RON = 0.06 Ω (typical at parallel connection)
• Reverse current protection at load side at switch OFF
• Operation start at low input voltage: VIN > 2.2 V (typical)
• Low power consumption
At switch OFF: IIN (input voltage) = 0 µA, VIN = 0 V
At switch ON: IIN = 230 µA, VIN = 5 V
• Load discharge function
• External control of ON/OFF time
• Break-before-make operation
■PACKAGE
(FPT-16P-M04)
16-pin plastic SOP
2
MB3802
■PIN ASSIGNMENT
■PIN DESCRIPTION (SCSI Interface)
Pin No. Pin symbol Description
16 VINAThese pins switch ON at High level and OFF at Low level. They
serve as power-supply pins for the DC/DC converter to generate
the switch gate voltage.
9VIN
B
3, 4 SWINASwitch Input pins: Two common pins are assigned to SWINA and
SWINB. The y serve as pow er-supply pins f or the s witch-OFF circuit
which starts at 1.5V min.
5, 6 SWINB
13, 14 SWOUTASwitch output pins: Two common pins are assigned to SWOUTA
and SWOUTB. When DCGA and DCGB are High level, the load-
discharge circuit starts discharge via these pins.
11, 12 SWOUTB
2DCG
ASWOUTA/SWOUTB-side discharge control pins: These pins are
used to discharge from the load-side capacitor at switch OFF.
Connect them to GND when discharge is not required.
7DCG
B
15 DLYASwitch-ON/OFF control pins: The ON/OFF time can be delayed
by connecting an external capacitor. Both times are delayed about
three fold by installing a 500-pF capacitor between these pins and
GND. Leave these pins open when they are not used. 10V may be
generated when these pins are open. To keep these pins at high
impedance, take care to mount the device so that no current leaks
(less than 0.1 µA).
10 DLYB
1GND
AGround pins for input threshold reference voltage and load
discharge: When two switching circuits are used, ground both
GND pins.
8GND
B
(TOP VIEW)
(FPT-16P-M04)
MB3802
1
2
3
4
5
6
7
8
VINA
DLYA
SWOUTA
SWOUTA
SWOUTB
SWOUTB
DLYB
VINB
16
15
14
13
12
11
10
9
GNDA
DCGA
SWINA
SWINA
SWINB
SWINB
DCGB
GNDB
3
MB3802
■BLOCK DIAGRAM AND EXTERNAL CONNECTIONS
■BLOCK DESCRIPTION
The MB3802 is a one-way switching IC with the SWIN and SWOUT pins serving respectively for input and output.
When VIN e xceeds 2.2 V, the Comp . starts driving the DC/DC conv erter to sw itch the N-ch MOS and applies the
optimum voltage for the switch gate.
The DC/DC converter boosts the VIN voltage.
When VIN is below 2.1 V, the Comp. stops the DC/DC conv erter, starts the switch-OFF circuit, and discharges
the voltage from the switch gate to GND . The switch-OFF circuit is powered from the SWIN and consumes 0.4µA
at 5 V.
Since the N-ch MOS back gate is connected to GND, switch-OFF reverse current is prevented irrespective of
the High level state between SWIN and SWOUT. Note, howev e r, that turning the VIN pin on/off with 1.5 V or less
applied to the SWIN pin may cause reverse current to flow because the switch-off circuit does not work then.
For the method of compensating for the operation of the switch-off circuit, see section “■APPLICATIONS 7.Low-
side Switch.”
The load discharge circuit installed between SWOUT and GND is powered by the DCG pin, and discharges the
load-side capacitor at s witch OFF. When it is not necessary to discharge the load, connect the DCG pin to GND .
The DLY pins are for connection to an exter nal capacitor to delay the switch-ON/OFF time. The surge current
at the load side is cut at power-on by controlling the switch-ON time. The switch-ON time depends on the boot
time of the DC/DC conv erter . Consequently, when the VIN lev el is high and the SWIN le v el is low, the s witch-ON
time is small; when the SWIN level is high, the switch-OFF time is small.
Power supply
V IN
C D
SW IN
SW OUT
GND
Extemal capacitor
DLY
DDG
(+)
Comp
DC/DC converter
Load Load discharge
circuit
Switch-OFF
circuit
Switch-ON
circuit
Switch control
Note: The MB3802 incorporates two switch blocks as shown above. However, GND is common to both blocks.
4
MB3802
■ABSOLUTE MAXIMUM RATING
(Ta = +25°C)
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.
■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 de vices within their recommended oper ating condition r anges . Oper ation
outside these ranges may adversely affect reliability and could result in device failure.
No warr anty 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
FUJITSU representatives beforehand.
Parameter Symbol Condition Ratings Unit
Input Voltage VIN — –0.3 to 7.0 V
Switching voltage VSW At switch OFF –0.3 to 7.0 V
At switch ON –0.3 to 7.0
Switching current ISW At switch-ON peak 3.6 A
Permissible loss PDTa ≤ + 75°C290mW
Storage Temperature TSTG — –55 to +125 °C
Parameter Symbol Conditions Ratings Unit
Min. Typical Max.
Input voltage VIN —0—6.0V
Switching level VSWIN At switch ON 0 — 6.0 V
At switch OFF 0 — 6.0
Switching current ISW At switch on
(for single switch) ——1.2A
Gate-pin connection capacitance CD———10nF
Gate-pin mounting leak current IDLY — –0.1 — 0.1 µA
Input voltage to load discharge circuit VDCG VIN = 3V, 5V 2.5 — 6.0 V
Operating temperature Top — –40 — +7.5 °C
5
MB3802
■ELECTRICAL CHARACTERISTICS
1. DC Characteristics
(Ta = +25°C)
2. AC Characteristics
(Ta = +25°C)
Parameter Symbol Condition Ratings Unit
Min Typ Max
Input current
IIN1 VIN = 0 V — 0 — µA
IIN2 VIN = 3 V — 100 200 µA
VIN = 5 V — 230 460 µA
Swiching resistance RON1 VIN = 3 V, ISW = 0.5 A,
VSWIN = 3 V — 120 160 mΩ
RON2 VIN = 5 V, ISW = 0.5 A,
VSWIN = 3 V — 130 175 mΩ
Switch-OFF leak current ILVIN = 0 V, VSWIN = 6 V — 0.5 2.0 µA
Input threshold voltage VTH1 At switch ON 2.0 2.2 2.4 V
VTH2 At switch OFF 1.9 2.1 2.3 V
Input hysteresis width VHYS — 50 100 — mV
Switch resistance RON VIN = 3 V, 5 V, ISW = 0.5 A
Ta = –40°C to +75°C— — 210 mΩ
Switch charge resistance RDCG1 VSWOUT = 3 V, VDCG = 3 V — 750 1500 Ω
RDCG2 VSWOUT = 5 V, VDCG = 5 V — 500 1000 Ω
Input voltage to switch charge
circuit IDCG VDCG = 5 V — 0 2 µA
Parameter Symbol Condition Ratings Unit
Min Typ Max
Switch-ON time tON1 VIN = 0V → 3V, VSWIN = 3V 20 300 900 µs
tON2 VIN = 0V → 5V, VSWIN = 5V 20 150 450 µs
Switch OFF time tOFF1 VIN = 3V → 0V, VSWIN = 3V 5 60 180 µs
tOFF2 VIN = 5V → 0V, VSWIN = 5V 5 30 150 µs
Switch ON/OFF time lag tHYS1 VIN = 3V / 0V, VSWIN = 3V 10 240 720 µs
tHYS2 VIN = 5V / 0V, VSWIN = 5V 10 120 300 µs
6
MB3802
■AC CHARACTERISTIC TEST DIAGRAMS
1. Test Condition
2. Switch-ON/OFF Timing Chart
Open
DLY
SWIN
SWOUT
VIN
GND DCG
1A
R
VS = 3 V/5 V
Load current = 1 A
R = 3 Ω/5 Ω
t r
tON
t OFF
90% 90%
90%
50% 50%
10% 10%
10%
0V
SWOUT
= SWIN
SW OUT
0V
0V
VIN
t f
Note: The rise/fall times (10%/90%) of VIN are both less than 1µs.
7
MB3802
■APPLICATIONS
1. Separate Use of Two Switching Circuits
2. Switching Two Power Supplies
VINA
DCGA
DCGB
VINB
VSB
3 V to 5 V
SWINA
SWOUTA
SWINB
SWOUTB
VSA
3 V to 5 V
GND
Load B Load A
Notes:
1. The two po wer supplies VSA andVSB can be used separated b y controlling the voltages VINA and VINB.
2. Connect the DCD pin to GND when it is not used.
VINA
GND
VINB
VSB
3 V to 5 V
SWINA
SWOUTA
SWINB
SWOUTB
VSA
3 V to 5 V
Load
Note: When using different power supplies for a single load, control them by connecting an external
capacitor so that both switches are not ON at the same time.
8
MB3802
3. Switching Two Loads
4. Connecting Serial Switches
VINA
DCGA
DCGB
VINB
SWINA
SWOUTA
SWINB
SWOUTB
VS
3 V to 5 V
GND
Load B Load A
Note: Make this connection to control two different loads separately for a single power supply.
VINA
DCGA
DCGB
VINB
SWINA
SWOUTA
SWINB
SWOUTB
VS
3 V to 5 V
GND
Load B Load A
Note: Make this connection to supply power from VS to load B via load A.
9
MB3802
5. Connecting Parallel Switches
6. 25% ON Resistance
VINA
DLYA
DLYB
DCGA
DCGB
VINB
SWINA
SWOUTA
SWINB
SWOUTB
VS
3 V to 5 V
GND
Load
Note: Connect the circuits A and B in parallel to produce a low ON resistance (RON = 0.06 Ω).
In this case, connect the DLYA and DLYB pins in common to give synchronous ON/OFF
between both switches.
VINA
DLYB
GND
GND
DLYA
DCGA
DCGA
DCGB
DCGB
VINB
VINA
VINB
SWINA
SWOUTA
SWINB
SWOUTB
VS
3 V to 5 V
SWINA
SWOUTA
SWINB
SWOUTB
Load
DLYB
DLYA
Notes:
1. Make this connection to produce an ON resistance that is much lower than the above connection.
Also, connect the DLY pins in common.
2. Consider the diff erence between the ON resistances and the s witch-ON/OFF times between tw o
devices (MB3802) and insure that load control is not offset at one device.
10
MB3802
7. Low-side Switc h
VINA
RBRA
VINB
SWINA
SWOUTA
SWINB
SWOUTB
VSAVSB
3 V to 5 V3 V to 5 V
GND
DLYA
VIN = 3 V,VS = 3 V
80 µs
5.0 ms
Switch-ON time
Switch-OFF time
RA and RB = 10 MΩ
45 µs
3.5 ms
VIN = 5 V,VS = 5 V
DLYB
Load A
Load B
Notes:
1. Make this connection to control the switch ON/OFF at the lower load side.
2. To assist the switch-OFF circuit operation driven by the SWIN power supply, connect high
resistances (RA and RB = 5 to 10 MΩ) to the DLY pins without overloading the DC/DC converter.
3. At this connection, the switch-OFF time is longer than the switch-ON time.
11
MB3802
■TYPICAL PERFORMANCE CHARACTERISTICS
(Continued)
Input voltage (V)
3.5 4.02.5 3.0 4.5 5.0 5.5 6.0
300
250
150
200
100
ON Resistance (Input-voltage dependence)
ON resistance (mΩ)
VSWIN = 6 V
VSWIN = 5 V
VSWIN = 4 V
VSWIN = 3 V
VSWIN = 2 V
VSWIN = 1 V
VSWIN = 0 V
ISW = 1 A
Load current (A)
0 0.2 0.4 0.6 0.8 1.0 1.2.
150
100
50
ON Resistance (Load current dependence)
Switch-ONTime (µs)
VSWIN = 5 V,VIN = 3 V
VSWIN = 5 V,VIN = 5 V
VSWIN = 3 V,VIN = 3 V
VSWIN = 3 V,VIN = 5 V
0–25 25 50 75
Ta (°C)
150
100
50
ON Resistance
(Temperature dependence: SWIN = 3 V)
ON resistance (mΩ)
VSWIN = 3 V
ISW = 1 A
VIN = 3 V
VIN = 5 V
0–25 25 50 75
150
100
50
ON Resistance
(Temperature dependence: SWIN = 5 V)
Ta (°C)
ON resistance (mΩ)
VSWIN = 5 V
ISW = 1 A
VVIN = 3 V
VVIN = 5 V
500
400
300
200
100
03.0 3.5 4.0 4.5
Input voltage (V)
Switch-ON time
(Input voltage characteristic: SWIN = 3 V)
Switch-ON time (µs)
5.0 5.5 6.0
VSWIN = 3 V
ISW = 1 A
Ta = –25°C
Ta = +25°C
Ta = +75°C
500
400
300
200
100
03.0 3.5 4.0 4.5
Input voltage (V)
Switch-ON time
(Input voltage characteristic: SWIN = 5 V)
Switch ONtime (µs)
5.0 5.5 6.0
VSWIN = 5 V
ISW = 1 A
Ta = –25°C
Ta = +25°C
Ta = +75°C
12
MB3802
(Continued)
Switch-OFF Time
(Input voltage characteristic: SWIN = 3 V)
100
90
70
80
50
60
3.0 3.5 4.0 4.5 5.0 5.5 6.0
Switch-OFF time (µs)
Input voltage (V)
Ta = –25°C
VSWIN = 3 V
ISW = 1 A
Ta = +75°C
Ta = +25°C
Switch-OFF Time
(Input voltage characteristic: SWIN = 5 V)
100
90
70
80
50
60
3.0 3.5 4.0 4.5 5.0 5.5 6.0
Switch-OFF time (µs)
Input voltage (V)
VSWIN = 5 V
ISW = 1 A
Ta = –25°C
Ta = +75°C
Ta = +25°C
VSWIN = 3 V
ISW = 1 A
100
10
1
0.1
100 1000 10000
Switch-ON Time
(DLY-pin connection capacitance: SWIN = 3 V)
ON-time (ms)
Capacitance (pF)
VIN = 3 V
VIN = 5 V
VSWIN = 5 V
ISW = 1 A
100
10
1
0.1
100 1000 10000
Switch-ON Time
(DLY-pin connection capacitance: SWIN = 5 V)
ON-time (ms)
Capacitance (pF)
VIN = 3 V
VIN = 5 V
10000
1000
100
10
100 1000 10000
Switch-OFF Time
(DLY-pin connection capacitance: SWIN = 3 V)
OFF-time (ms)
VSWIN = 3 V
ISW = 1 A
Capacitance (pF)
VIN = 3 V
VIN = 5 V
OFF-time (ms)
10000
1000
100
10
100 1000 10000
Switch-OFF Time
(DLY-pin connection capacitance: SWIN = 5 V)
VSWIN = 5 V
ISW = 1 A
Capacitance (pF)
VIN = 3 V
VIN = 5 V
13
MB3802
(Continued)
Discharge Resistance
(DCG voltage dependence: SWIN = 3 V)
10
1
0.123456
Discharge resistance (kΩ)
DCG voltage (V)
VSWIN = 3 V
ISW = 1 A
Ta = –25°C
Ta = +75°C
Ta = +25°C
Discharge Resistance
(DCG voltage dependence: SW
IN
= 5 V)
10
1
0.123456
Discharge resistance (kΩ)
DCG voltage (V)
V
SWIN
= 5 V
I
SW
= 1 A
Ta = +75°C
Ta = +25°C
Ta = –25°C
V
IN
= 0 V
Output Leak Current (at switch OFF)
1000
100
1023456
Leak current (nA)
SWIN voltage (V)
Ta = –25°C
Ta = +75°C
Ta = +25°C
Input Current (Input voltage dependence)
300
200
100
00 1.0 2.0 3.0 4.0 5.0
Input current (µA)
Input voltage (V)
Ta = –25°C
Ta = +75°C
Ta = +25°C
Switch-On resistance
(relationship between V
IN
and V
S
)
6
5
4
3
2
1
02.5 4.03.0 3.5 4.5 5.0 5.5 6.0
Switch voltage (V)
V
IN
voltage (V)
110 mΩ
105 mΩ
100 mΩ
115 mΩ
140 mΩ
I
SW
= 1A
130 mΩ120 mΩ
Surge Current and Output Voltage Boot
(DLY-pin connection capacitance dependence)
Output GND
Input GND
(Surge current)
Time
Open
510 pF Output voltage
1000 pF
Open
510 pF Surge current
1000 pF
VIN = 0 → 5 V V: 200 mA/div. (surge current)
SWIN = 5 V V: 1.0 V/div. (output voltage)
Load capacitance = 47 µF H: 200 µs/div. (time axis)
14
MB3802
■PACKAGE DIMENSIONS
+0.40
–0.20
+.016
–.008
+0.05
–0.02
+.002
–.001
+0.25
–0.20 +.010
–.008
INDEX 5.40
.213
0.15
.006
10.15 .400
(.252±.016)(.154±.012)
(.018±.004)
(STAND OFF)
(.020±.008)
0.50±0.20
3.90±0.30 6.40±0.40
8.89(.350)REF
0(0)MIN
2.10(.083)MAX
0.45±0.101.27(.050)TYP
Details of "A" part
0.50(.020)
0.20(.008)
0.18(.007)MAX
0.68(.027)MAX
"A"
M
Ø0.13(.005)
0.10(.004)
1994 FUJITSU LIMITED F16012S-4C-4
CDimensions in mm (inch)
(FTP-16P-M04)
16-pin plastic FTP
MB3802
FUJITSU LIMITED
All Rights Reserved.
The contents of this document are subject to change without notice.
Customers are advised to consult with FUJITSU sales
representatives before ordering.
The information and circuit diagrams in this document are
presented as examples of semiconductor device applications, and
are not intended to be incorporated in devices for actual use. Also,
FUJITSU is unable to assume responsibility for infringement of
any patent rights or other rights of third parties arising from the use
of this information or circuit diagrams.
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 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.
If any products described in this document represent goods or
technologies subject to certain restrictions on export under the
Foreign Exchange and Foreign Trade Law of Japan, the prior
authorization by Japanese government will be required for export
of those products from Japan.
F9902
FUJITSU LIMITED Printed in Japan
