The ISL97900 is a highly efficient 3-channel, 1.5A sequential

LED driver powered from a single-cell Li-ion battery, or

regulated input voltage up to 5.5V. This LED driver incorporates

an independent current controlled driving mechanism for each

of the LED's, which allows accurate current control of the LED

brightness.

The ISL97900 utilizes a buck-boost converter to ensure that

optimum output voltage is maintained for a wide range of LED

forward voltages. The integrated buck-boost converter

operates well over 90 efficiency across a wide range of

operating conditions. The power conversion core implements a

proprietary algorithm that allows seamless transitions and

glitch-free operation between the buck and the boost modes

as the battery voltage drops during operation.

The ISL97900 architecture includes a 10-bit DAC, which

controls the LED currents. Each of the LED currents can be

programmed through serial interface.

The ISL97900 also includes the Dynamic Headroom

Management function to provide seamless adjustment for the

LEDs’ voltages, which reduces power consumption.

Features

• Buck-boost based LED driver

• RGB color sequencing

• Up to 1.5A output current

• I2C Interface

• 150mV feedback voltage reference for current regulation to

maximize efficiency

• 2.5MHz switching frequency

• Programmable output voltage and output current for each

LED

• Dynamic headroom management

• Internal current setting registers

• Ambient temperature range: 0°C to +70°C

• Pb-free (RoHS compliant)

Applications

• LED-based pico projector in mobile phones

• Stand-alone pico projectors

• Tri-stimulus display drivers

• Other handheld display drivers