LED恒流式驅動電源 HV9923N8-G

HV9921/2 provide the most simple and efficient offline solution fordriving strings of high-brightness LEDs. The fixed OFF-time buck converter topology used in the solution has no duty cycle limitation, is free of current-mode instabilities. The peak-to-average errorassociated with peak current sensing technique of HV03 has little effect on the output current. The LED driver using HV03 supplies constant current (20mA forHV9921, 50mA for HV9922) directly from rectified universal 80-

264VAC input.

HV9922N3-GFeatures ‰ Constant Output Current (20mA/50mA) ‰ Universal 80-264VAC Operation ‰ Fixed OFF-Time Buck Converter

HV9922N3-GApplications：Decorative Lighting Low Power Lighting Fixtures

The HV9921/22 are pulse width modulated (PWM) high-efficiency LED driver control ICs. They allowefficient operation of LED strings from voltage sources ranging up to 400VDC. The HV9921/22include an internal high-voltage switching MOSFET controlled with fixed off-time TOFF of approximately10μs. The LED string is driven at constant current, thus providing constant light output and enhancedreliability. The output current is internally fixed at 20mA for HV9921 and 50mA for HV9922. The peakcurrent control scheme provides good regulation of the output current throughout the universal AC linevoltage range of 85 to 264VAC or DC input voltage of 20 to 400V.