HV9966

Supertex inc. Boost LED Driver with Low-side LED Wiring Fault Detection Features ►► ►► ►► ►► Switch mode controller for boost LED driver High output current accuracy Constant frequency operation Hiccup mode protection for both short circuit and open circuit conditions ►► LED wiring fault detection HV9966 General Description Applications The HV9966 is a current mode control LED driver IC designed to control a boost LED driver in constant frequency mode. The controller uses a peak current-mode control scheme (with programmable slope compensation) and includes an internal transconductance amplifier to accurately control the output current over all line and load conditions. The IC also provides a disconnect switch gate drive output, which can be used to achieve good PWM rise and fall times for the LED current using an external disconnect FET. The HV9966 also provides a TTL compatible, low-frequency PWM dimming input that can accept an external control signal with a duty ratio of 0-100% and a frequency of up to a few kilohertz. The HV9966 includes LED wiring fault detection function which turns off the boost converter and sends a shutdown signal to the external power supply in case the cathode of the LED string (or any tap in the LED string) is shorted to ground. A dedicated power supply input keeps the wiring fault detection circuitry armed even in the absence of the VCC supply. ► RGB or white LED backlighting Typical Boost Application Circuit VBST CIN L1 RIN ZD1 RSC RCS RO...