General Description

The LD7538 is built-in with several functions, protection

and EMI-improved solution in a tiny package. It takes less

components counts or circuit space, especially ideal for

those total solutions of low cost.

The implemented functions include low startup current,

green-mode power-saving operation, leading-edge

blanking of the current sensing and internal slope

compensation. It also features more protections like

OLP (Over Load Protection) and OVP (Over Voltage

Protection) to prevent circuit damage occurred under

abnormal conditions.

Furthermore, the Frequency Swapping function is to

reduce the noise level and thus helps the power circuit

designers to easily deal with the EMI filter design by

spending minimum amount of component cost and

developing time.

Features

 High-Voltage CMOS Process with Excellent ESD

protection

 Very Low Startup Current (<14A)

 Current Mode Control

 Green Mode Control

 UVLO (Under Voltage Lockout)

 LEB (Leading-Edge Blanking) on CS Pin

 Internal Frequency Swapping

 Internal Slope Compensation

 OVP (Over Voltage Protection) on Vcc Pin

 Adjustment OVP(Over Voltage Protection) on CS Pin

 Adjustment OCP(Over Current Protection) on CS Pin

 OTP (Over Temperature Protection) through a NTC

 OLP (Over Load Protection)

 250/-500mA Driving Capability

Applications

 Switching AC/DC Adaptor and Battery Charger

 Open Frame Switching Power Supply