General Description

The LD7837 is a high performance primary side Flyback

or Buck Boost LED Controller with HV start-up special

design for LED lighting. This IC operating on transition

mode(TM) and integrated with completed safety

requirement protections. It minimizes the components

counts in a SOP-7 package. Those make it easy design

for cost- effective applications.

This chip provides High Current Accuracy at full input

voltage range form from 85V to 277V Vac. The constant

on time PFC control and THDi compensator could easily

achieve PF>0.90 and THDi <10% to meet most of the

international standard requirements.

With completed protection built inside this IC, such as

over voltage protection (OVP), over current protection

(OCP) and short circuit protection (SCP), it enables the

circuit to meet most safety requirements in both normal

and abnormal test.

Features

 High voltage 700V startup circuit

 Primary Side PFC controller

 Optimize THDi Over Wide Universal Range

 High LED Current Accuracy

 Line Regulation 1%

 +/-10% output voltage variation Regulation +/-1%

 ± 5% Inductance variation ± 2%

 Power Saving 0.3W @ No Load VAC=264V

 Output Short Circuit Protection

 CS Short / Open Protection

 150/-450mA Driving Capability

Applications

 LED Power Module

 LED Bulb/Tube lighting