GENERAL DESCRIPTION

    AT9218 is comprised of 18 constant current channels each with independent PWM control, designed for driving LEDs. The output current of each channel can be set at up to 38mA (Max.) by an external resistor. The average LED current of each channel can be changed in 256 steps by changing the PWM duty cycle through an I2C interface.

       The chip can be turned off by pulling the SDB pin low or by using the software shutdown feature to reduce power consumption. The slave address is fixed “1010 1000”.

         AT9218 is available in QFN-24 (4mm × 4mm) and SOP-24. It operates from 2.7V to 5.5V over the temperature range of -40°C to +85°C.

FEATURES

• 2.7V to 5.5V supply

• I2C interface, automatic address increment function

• Internal reset register

• Modulate LED brightness with 256 steps PWM

• Each channel can be controlled independently

• -40°C to +85°C temperature range

• QFN-24 (4mm × 4mm), SOP-24 package

APPLICATIONS

• Mobile phones and other hand-held devices for LED display

• LED in home appliances

TYPICAL APPLICATION CIRCUIT