Does anybody try use HS nldmos as LS nldmos for your BUCK converter design?

[CHIPMUNK_kevin]

Hello ，

For BUCK converter design ，does anybody use isolated high side nldmos as isolated low side nldmos ？

If this works ？

Thnaks in advance .

 

[dick_freebird]

Not unless I could identify some benefit to the isolation
there (such as, maybe you're concerned about ground
bounce and the inductive nature of the gate drive loop).
But otherwise all you do is eat area unnecessarily.

 

[CHIPMUNK_kevin]

Thanks dick_freebird.

In our project , we usually use isolated LS nldmos for our project .This is because isolated LS could reduce the substrate noise greatly during dead time , especially for large load current application ,for example >5A, isolated is a must .By now , I know some company use the non-isolated nldmos LS in their design for 2A/3A BUCK converter , but for more high current , isolated is a must .

I ask this question is because we plan to use a new process , but they only supply isolated HS nldmos in their 1st PDK , so I want to know if I could use the isolated nldmos HS as isolated nldmos LS .

Thanks so much .