FUJI FA7610CN

Bipolar IC
FA7610CP(N)/12CP(N)/17CP(N)FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
For Switching Power Supply Control
■ Description
■ Dimensions, mm
The FA7610CP(N), 7612CP(N) and 7617CP(N) are bipolar
ICs containing basic circuits necessary for PWM-type
switching power supply control.
To minimize the number of external discrete components, the
FA7610CP(N) is provided for a flyback or step-up powersupply circuit, the FA7612CP(N) for a step-down power-supply
circuit and FA7617CP(N) for a flyback power supply circuit.
Á SOP-8
4
1
0.4±0.1
1.27±0.2
0~8°
0.20
1.7max
+0.1
–0.05
4.9
Á DIP-8
5
6.5
8
1
9.3
4
2.54±0.25
0.5±0.1
3.0min 4.5max
1.5
3.4
FA7612CP(N)
• For step-down power-supply circuit
(maximum output duty = up to 100%)
• Open collector output
• PWM-type switching power supply control
• Low-voltage operation (VCC = 3.6 to 22V)
• Latch-mode short-circuit protection function (no malfunction
by noise)
• Soft-start function
• Undervoltage lockout function
• One capacitor shared for short circuit protection and for softstart to minimize the number of external discrete components
6.0±0.2
3.9
■ Features
FA7610CP(N)
• For flyback transformer-type or step-up power-supply circuit
(maximum output duty = 64% typical)
• Totem-pole predriver
• PWM-type switching power supply control
• Low-voltage operation (VCC = 3.6 to 22V)
• Latch-mode short-circuit protection function (no malfunction
by noise)
• Soft-start function
• Undervoltage lockout function
• One capacitor shared for short circuit protection and for softstart to minimize the number of external discrete components
5
8
0.3
+0.1 5
–0.0
7.6
0~15
˚
5˚
0~1
FA7617CP(N)
• For flyback transformer-type power-supply circuit (maximum
output duty = 67% typical)
• Open collector output
• PWM-type switching power supply control
• Low-voltage operation (VCC = 3.6 to 22V)
• Latch-mode short-circuit protection function (no malfunction
by noise)
• Soft-start function
• Undervoltage lockout function
• One capacitor shared for short circuit protection and for softstart to minimize the number of external discrete components
■ Applications
• Battery power supply for portable equipment
1
FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
■ Block diagram
Á FA7610CP(N)
Pin
No.
Pin
symbol
Description
1
IN (–)
FB
GND
OUT
VCC
Inverting input to error amplifier
Capacitor for soft-start, short-circuit protection and delay
8
CS
CT
REF
Pin
No.
Pin
symbol
Description
1
IN (–)
FB
GND
OUT
Inverting input to error amplifier
Power supply
8
VCC
CS
CT
REF
Pin
No.
Pin
symbol
Description
1
IN (–)
FB
Inverting input to error amplifier
Ground
7
GND
OUT
VCC
CS
CT
8
REF
Reference voltage output (2.5V)
2
3
4
5
6
7
Error amplifier output
Ground
Output
Power supply
Oscillator timing capacitor
Reference voltage output (2.5V)
Á FA7612CP(N)
2
3
4
5
6
7
Error amplifier output
Ground
Output
Capacitor for soft-start, short-circuit protection and delay
Oscillator timing capacitor
Reference voltage output (2.5V)
Á FA7617CP(N)
2
3
4
5
6
2
Error amplifier output
Output
Power supply
Capacitor for soft-start, short-circuit protection and delay
Oscillator timing capacitor
FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
■ Absolute maximum ratings (Ta = 25°C)
Item
Symbol
Supply voltage
Reference voltage output current
Output current
Total power dissipation
Operating temperature
Storage temperature
Rating
Unit
FA7610C
FA7612C/17C
VCC
IOR
IO
22
22
V
5
5
mA
±50
80
mA
Pd
Topr
Tstg
400
400
mW
–20 to +85
–20 to +85
°C
–40 to +150
–40 to +150
°C
Symbol
FA7610C
■ Recommended operating conditions
Item
FA7612/17C
Min.
Max.
3.6
20
Oscillator timing resistance
VCC
RNF
CT
RT
Oscillation frequency
fOSC
Supply voltage
Feedback resistance
Oscillator timing capacitor
100
Unit
Min.
Max.
3.6
20
V
100
kΩ
220
22,000
220
22,000
pF
10
100
10
100
kΩ
5
200
5
500
kHz
■ Electrical characteristics (Ta = 25°C, VCC = 6V, RT = 33kΩ, CT = 1000pF)
Reference voltage section Common to FA7610C/12C/17C
Item
Symbol
Test condition
Typ.
Max.
Unit
Output voltage
VREF
LINE
IOR = 1mA
2.528
VCC = 3.6 to 20V, IOR = 1mA
2.580
2.632
V
4
12
mV
LOAD
VTC1
VTC2
IOR = 0.1 to 1mA
1
6
mV
Line regulation
Load regulation
Output voltage variation due to temperature change
Min.
Ta = –20 to +25°C
–1
1
%
Ta = +25 to +85°C
–1
1
%
Oscillator section Common to FA7610C/12C/17C
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Oscillation frequency
fOSC
fdV
fdT
CT = 1000pF, RT = 33kΩ
VCC = 3.6 to 20V
100
111
122
kHz
Frequency variation 1 (due to supply voltage change)
Frequency variation 2 (due to temperature change)
Ta = –20 to +85°C
1
%
5
%
Error amplifier section Common to FA7610C/12C/17C
Item
Symbol
Reference voltage
VB
IB
AV
GB
Input bias current
Open-loop voltage gain
Unity-gain bandwidth
Test condition
Output source current (Pin 2)
Typ.
Max.
Unit
0.525
0.535
V
5
100
70
RNF = 100kΩ
RNF = 100kΩ
VOM = 1V
nA
dB
0.6
VOM+
VOM–
IOM+
Maximam output voltage (Pin 2)
Min.
0.515
MHz
VREF–0.2
40
V
85
200
mV
200
µA
PWM comparator section
Item
Symbol Test condition
FA7610C
Min.
Max.
0.95
VTH0
VTH50
Duty cycle = 0%
0.85
Input threshold voltage (pin 2)
Duty cycle = 50%
1.1
Maximum duty cycle
αM
(Pin 2 = 1.2V)
Input threshold voltage (pin 2)
58
FA7612C
Typ.
64
Min.
FA7617C
Typ.
Max.
0.85
0.95
Min.
1.1
75
100
Unit
Typ.
Max.
0.85
0.95
1.1
63
67
V
V
71
%
3
FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
Soft-start circuit section Common to FA7610C/12C/17C
Item
Symbol
Input bias current (Pin 6)
IBCS
VTH CS0
VTH CS50
Input threshold voltage (Pin 6)
Input threshold voltage (Pin 6)
Test condition
Min.
Typ.
Max.
Unit
80
300
nA
Duty cycle = 0%
0.22
0.32
Duty cycle = 50%
0.46
V
V
Short-circuit protection circuit section Common to FA7610C/12C/17C
Item
Symbol
Test condition
Input threshold voltage (Pin 2)
VTH PC
ICHG
VTH LA
Pin 6 = 0V, Pin 2 = 2V
Charge current (Pin 6)
Latch-mode threshold voltage (Pin 6)
Min.
Typ.
Max.
Unit
1.20
1.50
1.80
V
20
30
40
µA
1.20
1.50
1.80
V
Min.
Typ.
Max.
Unit
Undervoltage lockout circuit section Common to FA7610C/12C/17C
Item
Symbol
OFF-to-ON threshold voltage
VTH ON
VTH OFF
VHYS
ON-to-OFF threshold voltage
Voltage hysteresis
Test condition
2.70
60
V
2.52
V
180
mV
Output section
Item
Symbol
Test condition
FA7610C
H-level output voltage (Pin 4)
RL = 10kΩ
L-level output voltage (Pin 4)
VOH
VOL
Output source current (Pin 4)
ISOURCE
Pin 4 = 0V
8
Symbol
Test condition
FA7610C
Min.
Typ.
3.5
4.0
Output sink
current = 20mA
FA7612C/17C
Max. Min.
—
0.25
0.65
11
14
—
Unit
Typ.
Max.
—
—
V
0.9
1.5
V
—
—
mA
Overall device
Item
Min.
FA7612C/17C
Typ.
Max. Min.
Typ.
Max.
Unit
Supply current
ICC LA
Latch mode
1.6
2.2
1.5
2.2
mA
Operating-state supply current
ICC AV
RL = ∞
2.6
3.8
1.8
3.0
mA
Duty cycle = 50%
4
FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
■ Characteristic curves (Ta = 25°C)
Oscillation frequency(fOSC ) vs.
timing capacitor capacitance(C T)
Output duty cycle vs. CS terminal voltage(VCS )
Output source current (Isource) vs.
supply voltage(VCC )
L-level output voltage(VOL ) vs. output sink current
(ISINK )
Supply current(ICC) vs. supply voltage(VCC)
Error amplifier frequency(f) vs. voltage gain(AV) / phase (θ)
5
FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
■ Application circuit
Á FA7610CP(N)
Flyback-transformer type converter circuit
Á FA7612CP(N)
Chopper type buck converter circuit
6
FA7610CP(N)/FA7612CP(N)/FA7617CP(N)
Á FA7617CP(N)
Flyback-transformer type converter circuit
330k
2.5V
180k
VCC
4.7µ
36k
0.01µ
R2
VCC
+
1000p
R3
Q1
8
7
VREF
OSC.
5
6
30µA
+
L.O
S.C.P
U.V.L.O
+
OFF
+
+
0.52V
+
+
ER.
AMP
1
TR
PWM
2
+5V
OFF
3
+
4
0.01µ
–5V
+
1k
2.2k
18.75k
Parts tolerances characteristics are not defined in the circuit design
sample shown above. When designing an actual circuit for a product,
you must determine parts tolerances and characteristics for safe and
economical operation.
Please connect a capacitor, which the value is about 0.01 µF to 0.1µF,
between VCC and REF terminals in order to prevent from irregular
output pulse at start up.
7