Question: we have the UCC28780 EVM ( 20v/45W) and its input is for universal AC line( 80 to 265?..50/60 Hz). We tested it & we like the results.
We have a half a dozen modules using that circuit but we have 380V input DC.
Do I need to change any component in the EVM to start testing with 380V DC input? .My thinking is for ac input at 265V, the peak rectified input is approx 375V , right?
So there may not be any changes necessary if we keep output 20V & current 2.25 Amp. Is this correct?
BTW: there was an effort to accommodate the calculations in the Spreadsheet ( sluc644b) for DC input a while ago. Do you know if that is available now?
Some of the values in the Input side really look strange when input is only DC.
Can I send you a file to make sure we got the input values consistent with DC input yet we have to insert the ac type values? Any help in adjusting the input power boundary values will be highly appreciated. Out input will be well regulated PFC output for 380VDC.
But as you can guess, each power form has its own set of values calculated from the spreadsheet but with the same input parameters. Only Rpp value comes out negative. We have mentioned that a while back. Do not if this has a correction now in the spreadsheet.
thnx much.
robin
