
1
■
Block diagram
FA5510P (N), FA5511P (N)
FA5514P (N), FA5515P (N)
FA551X series
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Dimensions, mm
SOP-8
FA5510P (N), FA5511P (N)
FA5514P (N), FA5515P (N)
■
Description
The FA551X series are the PWM type switching power supply
control ICs that can directly drive power MOSFET. These ICs
use a CMOS device with high dielectric strength (30V) to
implement low power consumption. These ICs contain many
function in a small 8-pin package. With these ICs, a high-
performance and compact power supply can be created
because not many external discrete components are needed.
■
Features
Low current consumption by CMOS process with high
dielectric strength (30V)
Standby current of 2μA or less (at Vcc=14V), and operating
current of 1.5mA (typ)
Overvoltage protection function detecting the Vcc voltage
A drive circuit for connecting a power MOSFET directly
Output peak current: ±1.5A
Pulse-by-pulse overcurrent limiting function
Overload protection function (latch or non-latch mode selectable)
Output ON-OFF function by external signal
Latch-mode overvoltage shutdown function
Undervoltage lockout function (16.5V ON / 9V OFF)
Reference voltage output (5V)
8-pin package (DIP/SOP)
CMOS IC
For Switching Power Supply Control
4.9
3
6
±
0
0.4
±
0.1
1.27
0
+
0
°
1
4
8
5
1
DIP-8
1
8
5
4
9.3
1.5
±
0.3
6
7.62
3
4
3
0~15
0~15
0.46
±
0.1
2.54
0.25
+0.1
Type
Max. duty
cycle (typ.)
Polarity of overcurrent Package
detection
FA5510P
46%
+
DIP-8
FA5510N
SOP-8
FA5511P
70%
+
DIP-8
FA5511N
SOP-8
FA5514P
46%
–
DIP-8
FA5514N
SOP-8
FA5515P
70%
–
DIP-8
FA5515N
SOP-8
0.8V/0.68V
8.5V/7.9V
5V VCC
ENB
5V REF
3.5V
4V
RT CT
OSC
+0.24V
R
S
QB
Q
ENB
OUT
16.5V/9V
UVLO
15.5V
15.5V
5.2
μ
A
0.95mA
PWM
0.8V
FA551Dmax
5V Controlled block
FB
(2)
REF
(7)
CS(8)
VCC(6)
OUT
(5)
GND
(4)
IS+(3)
RT(1)
FF
0.8V/0.68V
8.5V/7.9V
5V VCC
ENB
5V REF
3.5V
4V
RT CT
OSC
-0.17V
R
S
QB
Q
ENB
PUT
16.5V/9V
UVLO
15.5V
15.5V
5.2
μ
A
0.95mA
PWM
0.8V
FA55Dmax
5V Controlled block
FB
(2)
REF
(7)
CS(8)
VCC(6)
OUT
(5)
GND
(4)
IS-(3)
RT(1)
FF
Pin Pin
No. symbol
Function
Description
1
RT
Oscillator timing
resistor
Setting oscillation frequency
2
FB
Feedback
Input of PWM comparator
3
IS
Overcurrent
detection
Input of the overcurrent
limiting function
4
GND
Ground
Ground
5
OUT
Output
Output for driving a power
MOSFET
6
VCC
Power supply
Power supply
7
REF
Reference voltage
Reference voltage output (5V)
8
CS
Soft-start and
ON/OFF control
Soft-start, ON/OFF function and
latch-mode shutdown operations