Hi Kamal,
Here are the electrical specifications for the transformer. As Robert said, we do not specify the actual winding construction. GCI is the supplier for the transformer (part number G135049LF) on this reference design. GCI is happy to provide samples…
Hi Arion,
The varistors are there for surge protection, and do not play role in the actual power conversion. I don't think you will find any varistors that are significantly smaller, but if you already have surge protection elsewhere in your system you…
Hi Roy,
The only concern I see about sinking current would be at start up. The TPS40170 disables the low side FET during start up into a pre-biased output, so it will not be able to sink current during startup. Once startup is complete, it should be able…
Hi Sergio,
I agree with Robert that using our latest generation active clamp controller, UCC28782, will greatly reduce the amount of components because it integrates much more of these functions. To answer your questions:
1. Q100, Q101 and D101 eliminate…
Hi Mark,
I can't say for sure, because the schematic and BOM have the fuse holder listed rather than an actual part number for the fuse. However, it was likely the 37216300411 from Little Fuse, because it uses that style fuse holder and has an appropriate…
Hi Brant,
Optimizing the efficiency at a different switching frequency will require some tuning of the three items you mentioned (transformer design, FET selection, and timing of the SR FETs.) Lower Rdson is not necessarily better for higher frequency…
Hi Peter,
U3 can be eliminated, as the UCC2897A is capable of driving the primary FETs. Only be careful that the UCC2897A is not too far away from the FETs in the layout.
U1 and U4 are needed. These two drivers buffer the synchronous rectifier FETs from…