DPA Switch input voltage
Posted by: nsrprasad
on
DPA series is specified for 75V DC input maximum. From the block diagram, only L pin seems to be influenced by this input. Can we somehow manage the Lpin so that the input voltage range can be extended to 85V DC.
It would depend in part on what topology you choose. With a flyback, you may be able to choose a lower reflected voltage, which while increasing the peak primary current, and requiring a higher voltage output rectifier, also might make a higher Vin possible. With a forward topology, you will be bound by needing to reset the transformer core completely during the off time of the DPASwitch, which will limit your operating duty cycle. A larger duty cycle will require a higher off-time reset voltage, possibly exceeding the rating of the DPASwitch internal mosfet. You may also need to soft-clamp the L pin to allow higher operating voltage without tripping input OV shutdown.