Hello,
I am using UC21750 gate driver for a vienna rectifier application. I tied DESAT pin to COM, but still FLT pin is low.
Note: There are 6 gate driver on the board, two of them work as expected. Therefore;
1- I replaced the gate drivers with new ones
2- I removed the buffer to which the relevant FLT pins were connected.
3- I observed DESAT pin, it is always low (Connected to COM)
4- At the beginning of the program, all drivers' FLT pins are in HIGH state. FLT pins go low after switching starts.
Edit : 10kohm pullups connected to FLT RDY and RST pins.
My question is that what are the conditions could trigger FLT pin other than DESAT? Or could DESAT pin trigger FLT somehow even it is LOW.
Thank you in advance.