bogdan2011
Member
I'm building an IR2153 SMPS and I have a problem with the controller. HO doesn't switch, it stays high and blows the transistors. LO switches fine. I measured it both ways just to be sure:
- with HO referenced to GND I get HO high and no switching
- with HO referenced to VS (with an isolated scope, no diff probe, single channel) I get nothing
I also found the bootstrap diode was short circuited after the first power-up and replaced it. The weird thing is that I tested a handful of chips and they're all the same, so either they're fake or I'm doing something wrong.
- with HO referenced to GND I get HO high and no switching
- with HO referenced to VS (with an isolated scope, no diff probe, single channel) I get nothing
I also found the bootstrap diode was short circuited after the first power-up and replaced it. The weird thing is that I tested a handful of chips and they're all the same, so either they're fake or I'm doing something wrong.