matin-kh
Member level 3
problem with gilbert VGA
hi
at firs excuse me as i'm persian my english is not good enough ;-)
in the gilbert vga below what is the Vcm?I know that is common mode voltage but my question is that we have to initialize it??how much is that?
and the other question is if i want to have a vga with a specific frequency how can i calculate the frequency for this circuit?
i want to simulate it in the Hspice from wich point i can start my simulation i mean how can i get the w/l of transistors, i know i have to calculate something like dynamic range and wideband but i don't know how i can calculate the theory wideband of the circuit?
thank you so much
hi
at firs excuse me as i'm persian my english is not good enough ;-)
in the gilbert vga below what is the Vcm?I know that is common mode voltage but my question is that we have to initialize it??how much is that?
and the other question is if i want to have a vga with a specific frequency how can i calculate the frequency for this circuit?
i want to simulate it in the Hspice from wich point i can start my simulation i mean how can i get the w/l of transistors, i know i have to calculate something like dynamic range and wideband but i don't know how i can calculate the theory wideband of the circuit?
thank you so much
