Hi all -

I have to design a CMOS TIA which has to operate up to 400MHz with an AC coupled input (comming from an photo diode) and an input noise current density spec of <= 1pA/sqrt(Hz).

This noise spec seems quite taff!

Any idea what kind of architecture I could choose ?

I also have not seen any TIA differentially connected to the photo diode AC coupled. The only papers I find have a DC  coupling connection (single ended)..

Best regards,

tOM