Here is the top level spec:
Input voltage Range: 6 VDC to 36 VDC; ( off a battery )
Output Voltage: 12 VDC , +/- 5 %
Output Current: 5 Amps
Efficiency: > 90 %
Design is very $$ cost sensitive
Maximum Board Size: 2in x 2in , (somewhat negotiable!)
What topology should I use ? ;
it will most likely be a two stage design using Buck-Boost or SEPIC on the primary side ( boosted to 50-60VDC) follwed by a synchronous buck down to 12 VDC , with at least 1800VAC isolatiuon (automotive application requiremnet)
any ideas on how to carry out detailed circuit design, equations, magnetics, schematics ect
your help will be gretaly appriciated .....