HV9861A Datasheet, PDF (1/9 Pages) Supertex, Inc – LED Driver with Average-Mode, Constant Current Control

Supertex inc.
HV9861A
LED Driver with Average-Mode,
Constant Current Control
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^OC to +125^OC
►► Pin-compatible with the HV9910B and HV9961
Applications
►► DC/DC or AC/DC LED driver applications
►► LED backlight driver for LCD displays
►► General purpose constant current source
►► LED signage and displays
►► Architectural and decorative LED lighting
►► LED street lighting
General Description
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 (V_DD) for the HV9861A
is 7.5V.
The IC can be powered from a 12 - 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 Supertex HV9910B and
HV9961, and can be used as a drop-in replacement for many
applications to improve the LED current accuracy and regulation.
Typical Application Circuit
12 to
450VDC
1
VIN
5 _PWMD
GATE ⁴
HV9861A
6 VDD
CS 2
7 LD
RT
RT 8
GND
3
Sets
RCS LED
Current
LED
Load
Supertex inc. ● 1235 Bordeaux Drive, Sunnyvale, CA 94089 ● Tel: [phone] ● www.supertex.com