DS04-27201-3E
FUJITSU SEMICONDUCTOR
DATA SHEET
ASSP For Power Supply Applications
Switching Regulator Controller
MB3776A
■DESCRIPTION
MB3776A is a PWM system switching regulator controller. Because of its low operating supply voltage and power-
down, the MB3776A is ideal for use in DC/DC converters for battery-powered portable equipment.
■FEATURES
• Wide supply voltage range: (2 V to 15 V)
• Wide oscillation frequency range, high-frequency oscillation: (10 kHz to 500 kHz)
• Push-pull output. Drive current set with external resistor
• Bulit-in idle period circuit
• Internally set error amplifier gain, few external components
• Bulit-in power-down function
■PACKAGES
8-pin Plastic DIP
(DIP-8P-M01)
8-pin Plastic SOP
(FPT-8P-M01)
8-pin Plastic SOL
(FPT-8P-M02)
8-pin Plastic SSOP
(FPT-8P-M03)
2
MB3776A
■PIN ASSIGNMENT
2
1
4
3
–IN
CLT
V
CC
I
B
OSC
FB
OUT
GND
8
7
6
5
(TOP VIEW)
(DIP-8P-M01)
(FPT-8P-M01)
(FPT-8P-M02)
(FPT-8P-M03)
3
MB3776A
■BLOCK DIAGRAM
3 7
6
2
4
5
1
8
Output drive
control
Saw–tooth
waveform
Reference
voltage
Internal bias &
reference voltage
Error Amp.
–
+
–
+
+
VCC OSC
CTL
–IN
FB
GND
OUT
IB
Is
0.6 V
0.1 V
36 kΩ
30 kΩ
470 Ω
1.25 V
X 100
0.5 V D. T. C. ( 0.6 V)
0.1 V
P. W. M. Comp
IBIS
4
MB3776A
■ABSOLUTE MAXIMUM RATINGS
(Ta = +25°C)
* :The packages are mounted on the epoxy board (10 cm × 10 cm × 1.5 mm)
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: Recommended operating conditions are normal operating ranges for the semiconductor device. All
the device’s electrical characteristics are warranted when operated within these ranges.
Always use semiconductor de vices within the recommended operating conditions . Operation 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 representative beforehand.
Parameter Symbol Condition Rating Unit
Min. Max.
Power supply voltage VCC — — 16 V
Error amp. input voltage VI— –0.3 +10 V
Output source current ISOURCE — — –50 mA
Output sink current ISINK ——50mA
Power dissipation PD
Ta ≤ +25°C (DIP) — 550 mW
Ta ≤ +25°C (SOP) EIAJ — *570 mW
JEDEC — *430 mW
Ta < +25°C (SSOP) — *580 mW
Operating temperature Top — –30 +75 °C
Storage temperature Tstg — –55 +125 °C
Parameter Symbol Value Unit
Min. Typ. Max.
Power supply voltage VCC 2.0 — 15 V
Error amp. input voltage VI–0.2 — 1.0 V
Output source current ISOURCE –40 — — mA
Output sink current ISINK ——40mA
Phase compensation capacitor CP—0.1—µF
Timing capacitor CT100 1000 10000 pF
Timing resistor RT1.0 3.0 5.0 kΩ
Oscillator frequency fOSC 10 200 500 kHz
Operating temperature TOP –30 25 75 °C
5
MB3776A
■ELECTRICAL CHARACTERISTICS
1. Reference Section and Error Amp. Section (Ta = +25°C, VCC = 3 V)
2. Saw-tooth Waveform Oscillator Section (Ta = +25°C, VCC = 3 V)
3. Under Lockout Protection (Ta = +25°C, VCC = 3 V)
4. Dead-time Control Section (Ta = +25°C, VCC = 3 V)
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Input threshold voltage VTVFB = 450 mV 487 507 527 mV
VT input stability VTdV1 VCC = 2.0 V to 6.0 V –5 — 5 mV
VTdV2 VCC = 6.0 V to 15 V –5 — 5 mV
VT temp. stability VTdT Ta = –30°C to +75°C –3 — 3 %
Input bias current IBVIN = 0 V to 0.6 V –1.0 –0.2 1.0 µA
Voltage gain AV— 70 100 145 V/V
Frequency band width BW AV = 0 dB — 6 — MHz
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Oscillator frequency fOSC RT = 3.0 kΩ
CT = 1000 pF 160 200 240 kHz
Frequency input stability fdV VCC = 2.0 V to 15 V — ±2—%
Frequency temp. stability fdT Ta = –30°C to +75°C — ±10 — %
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Threshold voltage VTH — — 1.4 — V
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Max. duty cycle tDUTY CT = 1000 pF
RT = 3.0kΩ
VFB = 0.9 V 60 70 85 %
6
MB3776A
5. Output Section (Ta = +25°C, VCC = 3 V)
6. Control Section (Ta = +25°C, VCC = 3 V)
7. All Device (Ta = +25°C, VCC = 3 V)
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Output source current ISOURCE RB = 820 Ω, VO = 1 V –40 –30 –20 mA
Output sink current ISINK RB = 820 Ω, VO = 0.3 V 30 60 — mA
High-level output voltage VOH RB = 820 Ω, VO = 7 V
IO = –15 mA 5.5 6.0 — V
Output voltage VOL VCTL = VCC, IO = 3 µA — 0.1 0.2 V
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Input off condition IOFF — –300 — — µA
Input on condition ION — — — –700 µA
Control terminal current ICTL VCC = 7 V, VCTL = 0 V –1.3 –1 — mA
Parameter Symbol Condition Value Unit
Min. Typ. Max.
Stand by current ICCS VCTL = VCC or
CTL terminal open — — 0.5 µA
Average supply current ICC ICTL = –700 µA
RB = 820 Ω—4.5 8mA
7
MB3776A
■MEASURMENT CIRCUIT
TEST
INPUT
CTL
VCC = 3 V
MB3776A
RB
CP
CTRT
OUTPUT
ISOURCE
18
27
36
45
CT = 1000 pF
CP = 0.1 µF
RT = 3 kΩ
RB =820 Ω
ISOURCE 25000/RB (mA)
8
MB3776A
■DIAGRAM
FB Terminal Waveform
Saw-tooth Waveform
Output
Output Terminal Waveform
CTL Input Current
Power Supply Voltage
0 V
0 V
0 mA
ICTL
VCC
9
MB3776A
■TYPICAL CHARACTERISTIC
(Continued)
0
–10
–20
–30
–40
–50
0 –100 –200 –300 –400 –500 –600 –7000 –100 –200 –300 –400 –500 –600 –700
Output source current I
SOURCE
(mA)
Output bias current I
B
(µΑ)
0
0.2
0.4
0.6
0.8
1.0
0 –100 –200 –300 –400 –500 –600 –700
Output bias voltage V
B
(V)
Output bias current I
B
(µΑ)
180
190
200
210
170
160
150
–30 –20 0 20 40 60 75
Ambient temp. Ta (°C)
Oscillator frequency f
OSC
(kHz)
1 k
5 k
10 k
50 k
100 k
500 k
1 M
2 M
1 k 5 k 10 k 50 k 100 k 500 k
Oscillator frequency f
OSC
(Hz)
Timing resistor R
T
(Ω)
Output bias current vs. Output source current Output bias current vs. Output bias voltage
0 –6 –12 –18 –24 –30
0.0
1.0
2.0
“H” Level output current I
O
(mA)
“H” Level output voltage V
O
(V)
“H” Level output
02 4 6 8101214161820
0
100
200
0
100
200
“L” Level output voltage V
O
(mV)
“L” Level output current I
O
(mA)
“L” Level output
Ambient temp. vs. Oscillator frequency Timing resistor vs. Oscillator frequency
V
CC
= 2 V
Ta = +25°CV
CC
= 2 V
Ta = +25°C
V
CC
= 2 V
R
B
= 820 Ω
Ta = +25°C
V
CC
= 2 V
R
B
= 820 Ω
C
T
= 1000 pF
R
T
= 3 kΩ
V
CC
= 2 V
R
B
= 820 Ω
Ta = +25°C
V
CC
= 3 V
R
B
= 820 Ω
Ta = +25°C
C
T
= 100 pF
C
T
=
1000 pF
C
T
=
10000 pF
10
MB3776A
(Continued)
Control terminal voltage VCTL (V)
0
–0.5
–1.0
0.0 0.4 0.8 1.2 1.6 2.0
Control terminal current ICTL (mA)
0
–0.5
–1.0
0246810
Control terminal current ICTL (mA)
Control terminal voltage VCTL (V)
0246810
0
2
4
6
8
10
Inpurt on current VCTL (V)
Power supply voltage VCC (V)
Control terminal voltage vs.
Control terminal current
Power supply voltage vs. Input on voltage
Control terminal voltage vs.
Control terminal current
VCC = 2 V
Ta = +25°C
Ta = +25°C
VCC = 7 V
Ta = +25°C
11
MB3776A
■APPLICATION EXAMPLE
Synchronization
To synchronize MB3776A controllers , the OSC terminal of each IC is shared and the same specified capacitor
and resistor used on a signal IC application is connected for self-excitation oscillation. The CTL terminal controls
power on/off of each IC.
18 kΩ
10 µH
10 µH
10 µH
VIN (+3 V)
4.7 µF
CTL
2 kΩ
820 Ω
1000 pF
3 kΩ0.1 µF
10 µF10 µF
10 µF
10 µF
VO+ (+5 V)
VO– (–5 V)
1
2
3
4
8
7
6
5
+
–
+
–
+
–
+
–
+
–
CTRTOUT 1
OUT 2
OUT 3
MB3776A
MB3776A
MB3776A
VCC
12
MB3776A
■ORDERING INFORMATION
Part number Package Remarks
MB3776A-P 8-pin Plastic DIP
(DIP-8P-M01)
MB3776APF 8-pin Plastic SOP
(FPT-8P-M01)
MB3776APNF 8-pin Plastic SOL
(FPT-8P-M02)
MB3776APFV 8-pin Plastic SSOP
(FPT-8P-M03)
13
MB3776A
■PACKAGE DIMENSIONS
(Continued)
8-pin Plastic DIP
(DIP-8P-M01)
+0.30
–0
+.012 +.012
–0
+.016
–.012
–.012
+.014
–0
+0.30
–0
+0.40
–0.30
–0.30
+0.35
(.244±.010)
6.20±0.25
1 PIN INDEX
15°MAX
TYP
7.62(.300)
0.51(.020)MIN
(.010±.002)
0.25±0.05
(.018±.003)
0.46±0.08
TYP
2.54(.100)
3.00(.118)MIN
4.36(.172)MAX
.039 .060
.370
.035
1.520.99
9.40
0.89
1994 FUJITSU LIMITED D08006S-2C-3
CDimensions in mm (inches).
14
MB3776A
(Continued)
(Continued)
8-pin Plastic SOP
(FPT-8P-M01)
+0.40
–0.20
+.016
–.008
+0.05
–0.02
+.002
–.001
+0.25
–0.20 +.010
–.008
3.81(.150)REF
1.27(.050)
TYP
INDEX 6.80
.268
0.15
.006
6.35 .250
(.307±.016)(.209±.012)
(.018±.004)
(STAND OFF)
(.020±.008)
0.50±0.20
5.30±0.30 7.80±0.40
0.05(.002)MIN
2.25(.089)MAX
0.45±0.10
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 F08002S-4C-4
CDimensions in mm (inches).
15
MB3776A
(Continued)
(Continued)
8-pin Plastic SOL
(FPT-8P-M02)
+0.25
–0.20 +.010
–.008
45°
(STAND OFF)
(.020±.008)
Details of "A" part
0.20(.008)
0.40(.016)
0.18(.007)MAX
0.65(.026)MAX
"A"
(.006±.004)
(.197±.012)(.236±.016)
(.154±.012)
(.008±.002)(.017±.004) M
Ø0.13(.005)
0.10(.004)
5.05 .199
3.81(.150)REF
0.40(.016)
5.00±0.30
0.50±.020
6.00±0.40
3.90±0.30
0.15±0.10
1.55±0.20(.061±.008)
0.20±0.050.42±0.101.27(.050)TYP
1994 FUJITSU LIMITED F08004S-2C-4
CDimensions in mm (inches).
16
MB3776A
(Continued)
8-pin Plastic SSOP
(FPT-8P-M03)
+0.05
–0.02
+.002
–.001
+0.20
–0.10
+.008
–.004
Details of "A" part
0 10°
(STAND OFF)
0.10±0.10(.004±.004)
(.020±.008)
0.50±0.20
0.80(.0315)
TYP
*
INDEX
"A"
0.10(.004)
0.15
.006
1.25
.049
M
0.10(.004)
(.165±.004) (.244±.008)NOM
(.014±.004)
(.138±.004)
6.20±0.20
5.20(.205)4.20±0.10
2.40(.094)REF
0.35±0.10
3.50±0.10
1994 FUJITSU LIMITED F08005S-1C-2
CDimensions in mm (inches).
* : This dimension does not include resin protrusion.
MB3776A
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.
F9802
FUJITSU LIMITED Printed in Japan
