ISL97671A
6-Channel SMBus/I2C or PWM Dimming LED Driver with Phase Shift Control
Key Features
- 6 x 50mA channels
- 4.5V to 26.5V input with max 45V output
- 3V (see Figure 38) to 21V input with max 26.5V output
- PWM dimming with phase shift control
- SMBus/I2C controlled PWM or DC dimming
- Direct PWM dimming
- PWM dimming linearity
- PWM dimming with adjustable dimming frequency and duty cycle linear from 0.4% to 100% <30kHz
- Direct PWM dimming duty cycle linear from 0.007% to 100% at 200Hz
- Current matching ±0.7%
- 600kHz/1.2MHz selectable switching frequency
- Dynamic headroom control
- Fault protection
- String open/short circuit, OVP, OTP, and optional output short circuit fault protection
- 20 Ld 4mmx3mm QFN package
Description
The ISL97671A is a 6-Channel 45V dual dimming capable LED driver that can be used with either SMBus/I2C or PWM signal for dimming control. The ISL97671A can drive six channels of LEDs from an input of 4.5V~26.5V to an output of up to 45V. It can also operate from an input as low as 3V to an output of up to 26.5V in bootstrap configuration (see Figure 38).
The ISL97671A features optional channel phase shift control to minimize the input: output ripple characteristics and load transients to improve efficiency and eliminate audible noise.
The device can also be configured in Direct PWM Dimming with minimum dimming duty cycle of 0.007% at 200Hz.
The ISL97671A headroom control circuit monitors the highest LED forward voltage string for output regulation, to minimize the voltage headroom and power loss in a typical multi-string operation.
The ISL97671A is offered in compact and thermally efficient 20 Ld QFN 4mmx3mm package.
Applications
- Tablet PC to notebook displays LED backlighting
- LCD monitor LED backlighting
- Field sequential RGB LED backlighting


