Uploaded April 2024 | Updated September 2026, 2 weeks ago
I first had an issue with very low output even up to 100V and this was because of my feedback. Using the PLL circuit helped resolve that problem and now it works similar to the first build I made using the dual full bridge of 60N65's. I forgot to just add phase lead to the driver but that would also probably work. I wouldn't think the extra 90ns or so of delay the extra stage of drivers I added would make that big a difference but maybe it does.
I can't say it runs good at 300khz, but it runs. The bigger topload also helped. Aside from that actually shielding the PLL circuit completely was also necessary. I think since this build ended up so heavy I'm just going to leave it as a screwaround rig and use the miniblocs on another build I try to make smaller. I guess I can try to wind a lower frequency secondary and set this one with the bricks up for primary feedback at ZCS and try to really push it. I might also just hard switch it higher and higher just to see what happens.
I'll learn my lesson for the next one and actually source an enclosure before I start building it. Plan will be about 15,000uF in smaller caps. I think I'll also try a small GDT for the buck this time so its driver is completely isolated and I'll have some negative drive.
The brick PN is 2MB1200U2F-120 and I got them from old VFDs.
I first had an issue with very low output even up to 100V and this was because of my feedback. Using the PLL circuit helped resolve that problem and now it works similar to the first build I made using the dual full bridge of 60N65's. I forgot to just add phase lead to the driver but that would also probably work. I wouldn't think the extra 90ns or so of delay the extra stage of drivers I added would make that big a difference but maybe it does.
I can't say it runs good at 300khz, but it runs. The bigger topload also helped. Aside from that actually shielding the PLL circuit completely was also necessary. I think since this build ended up so heavy I'm just going to leave it as a screwaround rig and use the miniblocs on another build I try to make smaller. I guess I can try to wind a lower frequency secondary and set this one with the bricks up for primary feedback at ZCS and try to really push it. I might also just hard switch it higher and higher just to see what happens.
I'll learn my lesson for the next one and actually source an enclosure before I start building it. Plan will be about 15,000uF in smaller caps. I think I'll also try a small GDT for the buck this time so its driver is completely isolated and I'll have some negative drive.
The brick PN is 2MB1200U2F-120 and I got them from old VFDs.
