Part Number: UCC25661-Q1
Other Parts Discussed in Thread: UCC25661
The TEST pin can disable the PFC to reduce standby power loss when the LLC enters LF Burst mode. I have two questions:
- Must the LLC enter LF Burst mode first before the PFC can be disabled? Assuming the LLC enters HF Burst mode instead, can we still disable the PFC?
- After the LLC enters LF Burst mode and the PFC is turned off, what happens if the AC input voltage becomes very low? Can the PFC still remain off under this condition?I am currently using the UCC256610 chip, which features the EGR function. With this Input Voltage Gain Range extension function, does it allow the PFC to be disabled even when the AC input voltage is as low as 90 V?At this time, the peak voltage across the bus capacitor is only 127 V, which poses a significant challenge for LLC operation.
