WS3440 Datasheet, PDF (1/8 Pages) Shenzhen Winsemi Microelectronics Co., Ltd – Constant Current Controller For Non-isolated Buck LED Driver

WS3440 Product Description
Constant Current Controller For Non-isolated Buck LED Driver
Features
� Inductor Current Critical Mode, No Need to
Compensate the Inductance Variation
� Source Driver Structure, Not Need the Auxiliary
Winding for VCC
� ±3% LED Current Accuracy
� Up to 93% System Efficiency
� LED Short Circuit Protection
� Current Sense Resistor Short Circuit Protection
� Over Temperature Protection
� Programmable LED open protection
Applications
� LED Bulb
� LED Candle light
� LED Spot light
� Decorative LED lighting
General Description
The WS3440 is a high precision constant current controller，
designed for non-isolated buck LED driver. suitable for AC
input voltage range (84V-264V)
The WS3440 uses high precision current sense circuit and
patent method for constant current control, to achieve high
precision output current and excellent line regulation. The
WS3440 operates in inductor current critical mode. The LED
current is constant over wide range of inductance variation
and the LED output voltage, so the load regulation is
excellent.
The WS3440 uses patent source driver architecture. The
operation current is 200uA only, so the auxiliary winding is not
needed. It can simplify the system design and reduce the
system cost.
The WS3440 offers rich protection functions, including LED
open/short circuit protection, current sense resistor short
circuit protection and over temperature protection.
Typical Application Circuit
AC
1 ROVP G ND 2
6 V C C G ATE 5
3 CS
S4
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WIN SEM I M ICROELECTRON ICS
WIN SEM I M ICROELECTRON ICS
Copyright@Winsemi Microelectronics Co., Ltd., All right reserved.
WIN SEM I M ICROELECTRON ICS
W/T-Y027-Rev.A/1 May.2014
WIN SEM I M ICROELECTRON ICS
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