DATASHEET
ISL97698 FN8417
Rev.1.00
Sep 7, 2017 High Efficiency 2-Channel White LED Driver for Smartphone Backlighting
The ISL97698 is a highly integrated 2-channel LED driver for
white LED (WLED) backlit TFT-LCD panels. The device is
composed of a synchronous boost converter and two low-side
current sinks that are capable of driving an output voltage up
to 23.5V and 25mA LED current, per string. The ISL97698
operates from an input supply of 2.5V to 5.5V. Features The driver features Dynamic Headroom Control that monitors
the highest LED forward voltage string to determine the
requested boost output voltage. With a controlled low 70mV
headroom voltage and low 0.35mA IC supply current, the
device provides very high efficiency. Dynamic headroom control The ISL97698 offers 8-bit linear or 11-bit logarithmic
controlled analog output current, with dimming control from a
PWM, SWIRE, or I2C interface. Internally, the PWM duty cycle,
SWIRE, and I2C digital inputs are converted to a DC LED
current. This analog dimming scheme provides high efficiency
and eliminates audible noise and PWM dimming related EMI
concerns. The ISL97698 also features Content Adaptive
Backlight Control (CABC), which uses the product of the PWM
and SWIRE, or PWM and I2C, or SWIRE and I2C inputs to
determine the LED string current. The I2C interface is also …