PMP7848: 24~48V input, -77.5V/0.5A output

Part Number: PMP7848
Other Parts Discussed in Thread: LM5155, LM5156

Hi Team,

Good day !

My customer has two questions as below, please advise, Thanks!
(1) I am looking for a negative DC to DC converter (24~48V input, -77.5V/0.5A output). Please advise if you have any solution without using a transformer.
(2) If I want to generate +/-77.5V/0.5A and a +12V/0.2A referenced to -77.5V with a flyback transformer, please advise your suggested part.