How to measure dc offset in a mixer?!

[pop326]

mixer dc offset

Dear all,

How can I measure DC offset in a Gilbert mixer ?
Could anyone give me a good document of measurement environment ?

please help me, thanks in advance.

 

[huatangzeng]

how to measure dc offset

I also design mixer with Gilbert and have same problem !!!!

 

[tangqin55]

how to measure mixer

it is difficult for u to simulate dc offset of the mixer in schematic design as all circuits and devices are matched. you could set mismatch on some devices, for example, the load resistors(the easiest case) and then simu the dc offset. dc offset is mainly caused by self-mixing, 2nd nonlinearity and mismatch, among which the last one could be simulated.

i have designed a direct-conversion mixer and i think it is unnecessary to simu dc offset of your mixer 'cause double-balanced mixer has little mismatch. you could set mismatch and then simu the ability to reduce dc offset

 

[psmon]

how to measure dc offset from balanced output

Run monte carlo simulations to get mismatches in transistors.