PWM CONTROL 5A STEP-DOWN CONVERTER
FSP3132
FEATURES
GENERAL DESCRIPTION
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Input voltage: 3.6V to 23V.
FSP3132 consists of step-down switching regulator
with PWM control. These devices include a
reference voltage source, oscillation circuit, error
amplifier, internal PMOS and etc.
Output voltage: 0.8V to VCC.
Duty ratio: 0% to 100% PWM control
Oscillation frequency: 300KHz typ.
Soft-start, Current limit, Enable function
Thermal Shutdown function
FSP3132 provides low-ripple power, high efficiency,
and excellent transient characteristics. The PWM
control circuit is able to vary the duty ratio linearly
from 0 up to 100%. This converter also contains an
error amplifier circuit as well as a soft-start circuit
that prevents overshoot at startup. An enable
function, an over current protect function and a
short circuit protect function are built inside, and
when OCP or SCP happens, the operation
frequency will be reduced from 300KHz to 30KHz.
Also, an internal compensation block is built in to
minimum external component count.
Built-in internal SW P-channel MOSFET
SOP8L Package.
TYPICAL APPLICATION
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PC Motherboard
LCD Monitor
Graphic Card
DVD-Video Player
Telecom Equipment
ADSL Modem
Printer and other Peripheral Equipment
Microprocessor core supply
Networking power supply
With the addition of an internal P-channel Power
MOS, a coil, capacitors, and a diode connected
externally, these ICs can function as step-down
switching regulators. They serve as ideal power
supply units for portable devices when coupled with
PIN ASSIGNMENT
the
SOP8L mini-package,
providing
such
(Top View)
outstanding features as low current consumption.
Since this converter can accommodate an input
voltage up to 23V, it is also suitable for the operation
via an AC adapter.
FB
EN
1
2
8
7
VSS
VSS
3
4
6
5
OCSET
VCC
OUTPUT
OUTPUT
PIN DESCRIPTION
Pin Number Pin Name
Pin Description
Feedback Pin
Power-off Pin
1
2
FB
EN
H: Normal operation(Step-down operation)
L: Step-down operation stopped(All circuits deactivated)
3
4
OCSET Add an external resistor to set max output current
VCC
IC power supply pin
Switch pin. Connect external inductor/diode here. Minimize trace area at this pin to
reduce EMI.
OUTPUT
5,6
7,8
VSS
GND pin
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