
Catalog
LED Driver w/ Average-Mode Constant Current Control
Key Features
• + Fast average current control
• + Programmable constant off-time switching
• + PWM / linear dimming input
• + Output short circuit protection with skip mode
• + Ambient operating temperature -40°C to +125°C
• + Pin-compatible with the HV9910B and HV9961
Description
AI
The HV9861A is a patented, average-mode, constant current control LED driver IC operating in a constant off-time mode. Unlike the HV9910B, this control IC does not produce a peak-to-average error, and therefore greatly improves the accuracy, line and load regulation of the LED current without any need for loop compensation or high-side current sensing. The output LED current accuracy is ±3%.
The IC is equipped with a current limit comparator for hiccup-mode output short circuit protection. Internal over-temperature protection is provided. The internally regulated voltage (VDD) for the HV9861A is 7.5V.
The IC can be powered from a 15 - 450V supply. A PWM dimming input is provided that accepts an external control TTL-compatible signal. The output current can be programmed by an internal 270mV reference, or controlled externally through a 0 - 1.5V dimming input.
The IC is pin-to-pin compatible with the HV9910B and HV9961, and can be used as a drop-in replacement for many applications to improve the LED current accuracy and regulation.