• Three out-of-phase constant-current boost
converters
• Current loop closed, with sub-microsecond PWMdimming
pulses, supports PWM dimming >20 kHz
• Internal 40V linear regulator
• External clock input
• External individual reference inputs
• Individual PWM dimming inputs
• Programmable slope compensation
• +0.2A/-0.4A gate drivers
• Independent short circuit protection with hiccup
for each channel
• Latching output open-circuit protection

Applications
• LCD panel back-lighting

HV9989 is a three-channel peak current mode PWM
controller designed to drive single switch converters in
a constant-output current mode. It can be used for driving
either RGB LEDs or multiple channels of white
LEDs.
HV9989 features a proprietary PWM-dimming control
algorithm that achieves a dimming pulse of a few hundred
nanoseconds from a Continuous-Conduction
Mode (CCM) or Discontinuous-Conduction Mode
(DCM) boost converter, while maintaining the instantaneous
LED constant current determined by the external
reference voltage input. This feature permits a dimming
frequency outside of the audible range, and can also
yield a wide dimming ratio in excess of 10,000:1 at low
dimming frequency. Each of the three channels features
individual PWM-dimming and reference voltage
inputs.
The switching frequencies of the three converters are
controlled by an external clock signal, such that the
channels operate at a switching frequency of 1/12th the
external clock frequency, and are positioned 120° outof-
phase to reduce the input current ripple.
HV9989 provides a full protection feature set, including
output-short and open-circuit protection, for each individual
channel that is independent from the other channels.
HV9989 is powered by a built-in 40V linear regulator.