G1552
High Performance Current Mode PWM Switch
ANALOG PWM IC
1. General Description
The G1552 is a high performance AC/DC power
supply Switch for battery charger and adapter
applications requirements up to 8W in an open
frame design.It can meet less than 80 mW
standby power.
G1552 is a current mode PWM Switch with a high
voltage power MOSFET. It operates in fixed
frequency which is precisely set internally. It
could operate in Extended Burst Mode at no load
or light load, in which mode switching loss is
minimized and the frequency is adjusted
internally. To ensure that power supplies work
quietly, the frequency is set beyond 20 KHz.
Small current is needed when G1552 starts up
and works, thus a large value resistor could be
used in the startup circuit to minimize the standby
power. Slope compensation circuit is integrated
in G1552, which improves system large signal
stability and reduces the possible sub-harmonic
oscillation at high PWM duty cycle.
Frequency shuffling technique is integrated in
G1552, which helps to achieve excellent EMI
performance.
G1552 offers complete protection functions
including cycle-by-cycle current limiting
protection(OCP), over load protection(OLP),VDD
over voltage protection(OVP), VDD over voltage
clamp and under voltage lockout(UVLO).
The G1552 is available in SOP7 and DIP8
package.
Features
◆ Built-in Soft Start
◆ Random Frequency Adjustment to
Reduce System EMI
◆ Audio Noise Free Operation
◆ Internal Cable Compensation
◆ Extended Burst Mode Control For
Improved Efficiency and Minimum
Standby Power Design
◆ Internal Synchronized Slope
Compensation
◆ Low VDD Startup Current and Low
Operating Current
◆ Leading Edge Blanking on Current
Sense Input
◆ Over Load Protection(OLP) and
Cycle-by-Cycle Current Limiting
Protection(OCP)
◆ Over Voltage Protection (OVP),
Under Voltage Lockout Protection
(UVLO) and Over Voltage Clamp
Applications
● Offline AC/DC flyback converter
● Power Adapter
● Set-Top Box Power Supplies
● Open-frame SMPS
● Auxiliary Power Supply for PC and
Server
● Digital Cameras and Camcorder
Adapter
Global Semiconductor Co., LTD.
1 of 10
