Preliminary WS2801

3-Channel Constant Current

LED Driver With Programmable

PWM Outputs

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WS-Preliminary-V0.3

http://www.world-semi.com

　

Features

　

Applications

• Supports both constant voltage and constant current drive mode

• Programmable constant LED drive current

• Wide constant output current range 5~150mA

• Build in PWM dimming scheme for each output channel,

supports free-run, especially suitable for low cost controller

application

• PWM free-run capability(refresh rate(2.5KHz)

• Build in buffers to cascading data and clock to the next driver

• Output polarity reverse function

• Support hot swap

• Maximum input clock frequency 25MHz

• Power supply voltage 3.3~5.5V

• LED decorative lighting

• Indoor/Outdoor LED video or massage display

• PWM signal generator

• LCD TV back lighting

　

General Description

The WS2801 is a constant current LED driver. It is designed for indoor/ outdoor LED displays and decorative LED lighting system.

It is suitable for LED cascading applications. The WS2801ownes 3 output channels, each channel can drive a constant current up

to 30mA. WS2081 contains serial shift registers, data latches, output registers, band gap reference voltage generator, internal

oscillator, and programmable constant output current drivers. The serial data is read into the shift registers at the rise edge of the

external clock. The data and clock output buffers are designed for cascading another chip. The output polarity reverse function is

designed for driving high power LED by adapting the application circuitry. The WS2801 adopts the reliable 2-wire scheme, which

features low EMI transport, very strong anti-interference ability, and support hot-swap. The 2-wire control scheme can reduce the

system cost; it is very suitable for low cost LED decorative LED lighting systems.

WS2801 is available in both SOP-14 and DIP-14 packages, the operating temperature is -40~85℃

　

Pin Configurations

　

Fig1.a SOP-14 package

Fig1.b DIP-14 package

　

　

Typical Application Circuit