Synchronization of ringing choke converters

[japlytic]

Depending on the design, some ringing choke converters can be synchronized from an external source - a common example were the "live chassis" TV sets, mainly from the 70s to 80s of which the converter was synchronized to TV Horizontal frequency.

I've even seen a ringing choke converter which the synchronization signal is electrically isolated by an overwind on the flyback transformer in a Casper TM5158A monitor (the circuit diagram should show this winding is actually isolated).

Syncrhonizing ringing choke converters should be done with caution, since a frequency which is out of range (or something incorrectly designed) can cause failure of the converter.

[ben7]

Re: Synchronization of ringing choke converters

Syncrhonizing ringing choke converters should be done with caution, since a frequency which is out of range (or something incorrectly designed) can cause failure of the converter.

I had a feeling that is so .. :P

[fzabkar]

Re: Synchronization of ringing choke converters

Depending on the design, some ringing choke converters can be synchronized from an external source - a common example were the "live chassis" TV sets, mainly from the 70s to 80s of which the converter was synchronized to TV Horizontal frequency.

Yes, I've seen those, although I've never really understood why this was done. Would the B+ capacitor be charged by the SMPS at the same time as the pulse from the horizontal output stage is discharging it, and would this then minimise the ripple?