Hi Yue Tang,
For 200W, a single phase CrM PFC followed by a half bridge LLC would work (UCC28051 + UCC25640x). Something similar to PMP5761: http://www.ti.com/tool/PMP5761 . Another approach would be to look at a single stage CCM flyback (UCC2863x).
Best…
Hi Edward,
Thanks for bringing this opportunity to us. PMP5761 has some similarity to your customer's spec: http://www.ti.com/tool/PMP5761 . This is a 40Vac to 90Vac with 84W output
Since your customer needs 200W and ability to work at lower input voltage…