Unitrode UC1863
The UC1861-1868 family of ICs is optimized for the control of Zero Curor Zero Voltage Switched (ZVS) rent Switched and Zero Voltage Switched quasi-resonant converters.FEATURES
DESCRIPTION
● Controls Zero Current Switched (ZCS) DifQuasi-Resonant Converters ferences between members of this device family result from the various combinations of UVLO thresholds and output options. Additionally, the● Zero-Crossing Terminated One-Shot one-shot pulse steering logic is configured to program either on-time for Timer ZCS systems (UC1865-1868), or off-time for ZVS applications (UC1861● Precision 1%, Soft-Started 5V 1864). Reference The primary control blocks implemented include an error amplifier to com● Programmable Restart Delay pensate the overall system loop and to drive a voltage controlled oscillator Following Fault (VCO), featuring programmable minimum and maximum frequencies. Triggered by the VCO, the one-shot generates pulses of a programmed maxi● Voltage-Controlled Oscillator (VCO) mum width, which can be modulated by the Zero Detection comparator. with Programmable Minimum and Maximum Frequencies from 10kHz to This circuit facilitates “true” zero cu...