DATASHEET
ISL78171 FN8602
Rev.1.00
Oct 20, 2017 6-Channel, 50mA Automotive LED Driver with Ultra-High Dimming Ratio and
Phase Shift Control
The ISL78171 is a 6-channel, 50mA, LED driver capable of very
high dynamic range dimming. It offers an integrated boost
converter, six high precision, adjustable current sinks and a
SMBus/I2C interface for digital programmability and extensive
diagnostics. These features provide the ISL78171 with the
capabilities to design a compact, highly versatile LED backlight
for a wide variety of ambient lighting conditions. Features The integrated peak current mode PWM boost converter
operates with a constant frequency and can boost an input
voltage range of 4.5V -26.5V to an output up to 40V and supply
six strings of LEDs with up to 50mA each. A dynamic headroom
control circuit detects and regulates the highest voltage string to
improve efficiency in multistring configurations. SMBus/I2C controlled PWM or DC dimming 6 channels at 50mA maximum per channel Input voltage: 4.5V to 26.5V, output voltage: 40V max Bootstrap operation Input:3V to 21V output: 26.5V max PWM dimming with phase shift control Direct PWM dimming Internal PWM dimming mode linearity: 0.4% to 100%,
dimming frequency <30kHz Direct PWM dimming duty cycle linearity: 0.007% to 100%
at a dimming frequency of 200Hz The six high precision adjustable current sinks offer typical
current matching better than В±1% and a dimming ratio
capable of exceeding 60,000:1. The dimming ratio can be
adjusted with either or both the I2C/SMBus and an external
PWM signal. They also feature an optional channel phase shift …
