Overview

     As a direct replacement for PCA9551, AT9551 provides the ability to drive 8 parallel LEDs for backlight and RGB color mixing applications. This device can also turn on, off or blink each LED individually (there are two programmable schemes for the blinking frequency). The chip integrates an oscillator circuit and has a programmable flash control driving function. In addition, the device can realize sensor control, power switch, switch button and status indication lighting through I2C or SMBus interface.

Product Features

Drive 8 LEDs and provide programmable flash function;

Internal power-on reset;

8 open-drain outputs, each driving current is 25mA;

Two programmable flashing frequencies: 0.15625 Hz to 40 Hz (6.4 / 0.025 seconds);

Internal integrated oscillator circuit, no external components required;

Operating voltage range: 2.3V ~ 5.5V;

I / O can be used as a general-purpose I / O port;

Support hot swap;

Low standby circuit

Compatible with 400kHz I2C bus specification;

Package: 16-lead SOP, TSSOP or 16-pad TQFN package (size 4x4mm)

Structure diagram

Typical circuit