YOUDA INTEGRATED CIRCUIT

YD3843

CURRENT MODE PWM CONTROL CIRCUITS—YD3843

DESCRIPTION

The YD3843 provides the necessary features to implement off-line or DC to DC fixed frequency current mode

control schemes with a minimal external parts count.

FEATURES

*Optimized for off-line and DC to DC converts

*Low start up current(<1mA)

*Automatic feed forward compensation

*Pulse-by-Pulse current limiting

*Enhanced load response characteristic

*Under-voltage lookout with hysteresis.

*Double pulse Suppression

*High current totem pole output

*Internally trimmed band-gap reference

*500kHz operation

*Low Ro error amp

BLOCK DIAGRAM

876

1/2

1/3

VCC

5V

REF

S/R

UVL

5

1

2

3

4

RS

OSC

+

-

EA

1V

WuXi YouDa Electronics Co., Ltd

Add:

No.5 Xijin Road, National Hi-Tech Industrial Development Zone, Wuxi Jiangsu China

Tel:

86-510-85205117

86-510-85205106

Fax:

86-510-85205110

Website: www.e-youda.com

SHENZHEN OFFICE

Tel： 86-755-83740369

Fax： 86-755-83741418

Ver

5.0

1 of 4

2006-7-10