Other Parts Discussed in Thread: UCC256403
Hi,
During no-load operation, the output voltage is 71.4V. When a 30-ohm pure resistive load is applied, the circuit operates normally with the red indicator light on, the fan running, and the output voltage remaining stable. However, when the load is changed to 20 ohms (approximately 254W), the fan stops, the output voltage drops to 0V, and even after switching back to a 30-ohm load or no load, the output voltage remains at 0V. Upon inspection, the voltage at the LL/SS pin of the UCC256403 is measured at 1.26V. After replacing the chip, the output voltage returns to normal and the fan starts again. What could be the cause of this issue? Additionally, is the UCC256403DDBR a latching-type chip? I would appreciate it if an expert could clarify these questions for me.
Thank you.
