WS3253 Datasheet, PDF(1/11 Page) Shenzhen Winsemi Microelectronics Co., Ltd – High Precision Primary-Side Off-line PWM Power Switch

English

English German Russian Spanish Italian Polish Chinese Japanese Korean French Portuguese	Language :

WS3253 Datasheet, PDF (1/11 Pages) Shenzhen Winsemi Microelectronics Co., Ltd – High Precision Primary-Side Off-line PWM Power Switch

WS3253 Product Description

High Precision Primary-Side Off-line PWM Power Switch

Features

ï¿½ 5uA ultra-low startup current

ï¿½ 2mA Low operating current

ï¿½ Â±5% Constant Voltage Regulation at Universal AC

input

ï¿½ Primary-side Sensing and Regulation Without

TL431 and Opto-coupler

ï¿½ Programmable CV and CC Regulation

ï¿½ Built-in Primary winding inductance compensation

ï¿½ Programmable cable drop compensation

ï¿½ Built-in soft start

ï¿½ Built-in Leading-edge blanking

ï¿½ Cycle by cycle over current protection (OCP)

ï¿½ VCC over voltage clamp & under voltage

lockout( UVLO)

ï¿½ Maximum Gate output voltage clamped at 12V

ï¿½ Frequency jittering

ï¿½ Ultra low standby power (<100mW)

Applications

Low power AC/DC offline SMPS for

ï¿½ Cell Phones/Cordless phones Charger

ï¿½ Digital Cameras Charger

ï¿½ Small Power Adapter

ï¿½ Auxiliary Power for PC, TV etc.

ï¿½ Linear Regulator/RCC Replacement

General Description

WS3253 is a high-integrated offline PWM power switch,

optimized for high performance low power AC/DC

charger and adapter application.

WS3253 operates in primary-side sensing and

regulation. Consequently, optocoupler and TL431 could

be eliminated, thus reduce the cost. It can achieve Â±5%

constant voltage precision in full input voltage range. CC/CV

Control as shown in fig.1.In CC Control, the

current and output power setting can be adjusted externally

by the sense resistor Rs at CS pin. In CV control, multi-mode

operations are utilized to achieve high performance and high

efficiency. In addition, good load regulation is achieved by

the built-in cable drop compensation. Device operates in

PFM in CC mode as well at large load condition and it

operates in PWM with frequency reduction at light/medium

load.

Icc

Fig.1 Typical CC/CV Curve

WS3253 offers power on soft start control and protection

coverage with auto-recovery features

including Cycle-by-Cycle current limiting, VCC

OVP, VCC clamp and UVLO. The gate-driven output is

clamped to maximum 12V to protect the internal MOSFET.

Excellent EMI performance is achieved by using the

soft-switching and frequency jittering at the

totem-pole-gate-drive output. The WS3253 is the ideal

substitute of the linear power supply or the RCC-mod e

power, for a better performance of the whole switch power

system and a lower cost.

WS3253 is available in DIP8 and SOP8 package.

WINSEM I M ICROELECTRONICS

W/T-DS011-Rev.A/2 May.2014

WINSEM I M ICROELECTRONICS

0612

▷