ISL97674
6-Channel LED Driver with Phase Shift Control and Frame Rate to Dimming Frequency Synchronization
Not Recommended for New Designs.
Recommended Replacement Parts ISL97671A, ISL97672B.
Key Features
- 6 Channels
- Frame Rate to Dimming Frequency Synchronization
- 4.5V to 26.5V Input
- 45V Output Max
- Up to 40mA LED Current per channel
- Extensive Dimming Control
- PWM/DPST Dimming, I2C 8-bit with equal phase shift, and 0.007% Direct PWM dimming at 200Hz
- Optional Master Fault Protection
- PWM Dimming Linearity 0.4%~100% <30kHz
- 600kHz/1.2MHz selectable switching frequency
- Dynamic Headroom Control
- Protections with Flag Indication
- String Open/Short Circuit, VOUT Short Circuit, Overvoltage and Over-Temperature Protections
- Optional Master Fault Protection
- Current Matching ±0.7%
- 20 Ld 4mmx3mm QFN Package
Description
The ISL97674 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 ISL97674 drives 6 channels of LED to support 78 LEDs from 4.5V to 26V or 48 LEDs from a boost supply of 2.7V to 26V and a separate 5V bias on the ISL97674 VIN pin.
The ISL97674 compensates for non-uniformity of the forward voltage drops in the LED strings with its 6 voltage controlled-current source channels. Its headroom control 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 ISL97674 features optional channel phase shift control to minimize the input, output ripple characteristics and load transients as well as spreading the light output to help reduce the video and audio interference from the backlight driver operation. The phase shift can be programmed with equal phase angle or adjustable in 7-bit resolution. In addition, the ISL97674 also has a unique VSYNC function that accepts 30Hz ~ 120Hz frame signal and synchronizes it to the dimming frequency to minimize panel to panel visual interference variation. The dimming frequencies are available from 200Hz to 30kHz and can be synchronized from 140Hz to 1085Hz.
Applications
- Notebook Displays WLED or RGB LED Backlighting
- LCD Monitor LED Backlighting
- Automotive Displays LED Backlighting
