NCP1380B Application Problem

For general questions regarding the software and for all questions that do not fit in any of the threads above.
Post Reply
Message
Author
Deion Adel
Posts: 12
Joined: 26 Apr 2021, 21:48
Contact:

NCP1380B Application Problem

#1 Post by Deion Adel » 31 May 2021, 22:19

;) Hey, guys! Now I have an NCP1380B application problem. It's about the switch between QR mode and VCO mode.

Using NCP1380B as a switching power supply, the output voltage is 24V, 3.75A. The no-load power consumption is below 0.5W when the input voltage is 220Vac, but the no-load power consumption is above 0.7W when the input voltage is 110Vac. :shock: What should I do?

(1) At 220Vac, the switching frequency can be reduced to 5KHz. At 110Vac, the switching frequency is 19KHz.

(2) If the output voltage is changed to 19V, the switching frequency can be reduced to below 5KHz regardless of whether it is 220Vac or 110Vac, and the no-load power consumption is below 0.5W

Can't find the problem, has anyone done the design of this IC?
Thanks in advance! :)

The circuit 24V5A.pdf

Post Reply