now , we have a project of dual-battery source to design, it select the LT4359 for ideal diode and load switch. but it still have some problem during debug:
1) the oring circuit include both of source : one is li-ion battery , another is fuel battery , firstly, li-ion is working and fuel battery will be turned on at 800W,
(li-ion battery =48V , fuel battery =0-75V depended on the load and current, the higher the voltage rise , the heavier the load work),
2) when the voltage of fuel cell is 60V set by microprocessor , it will turn off LT4359 and NMOS, it's easy to be broken with the input NMOS , the current of this time
is only 5-15A, the NMOS is selected the IRLB4030 (IDSS=180A, VDSS=100V) and the SOA is enough
3) it adopt to the back-to-back NMOS to build this circuit and refer to the ADI demo circuitPDFPDF attachment is the schematic drawing and NMOS SPEC
Can you clarify what the exact issue is?
If it is about the NMOS broken during high current, make sure the gate drive is enough to really turn it fully on. Also, at pretty high load current, you may need heat sink on the FETs.
thanks for replaying my email, i use the new type of NMOS: PSMN4R8-100PSE instead of old one ,but input NMOS (back to back) is still easy to be broken on 9A and the SOA is enough to support this (switch channel: 60V@20A), also, the gate drive is fully on using the LTC4359 and can support to 50V@50A for several hours