The HV9925 is a pulse width modulated (PWM) high-efficiency LED driver control IC with PWM dimming capabilities. It allows efficient operation of high brightness LED strings from voltage sources ranging up to 400VDC. The HV9925 includes an internal high-voltage switching MOSFET controlled with a fixed off-time TOFF of approximately 10s. The LED string is driven at constant current, thus providing constant light output and enhanced reliability. Selecting a value of a current sense resistor can externally program the output LED current of the HV9925. The peak current control scheme provides good regulation of the output current throughout the universal AC line voltage range of 85 to 264VAC or DC input voltage of 20 to 400V. The HV9925 is designed with a built in thermal shutdown to prevent excessive power dissipation in the IC.