How to do AC analysis of a 4 quadrant analog multiplier

[mohdiliyasmalik]

hi
i m designing 4 quadrent analog multiplier. there r four ip terminal in my strecture.
i m giving V1+v1, V1-v1, V2+v2, V2-v2, signal at the input terninals, where V is D.C. bias and v is analog signal. i m gettin correct out put.but i dont know how can i do a.c. analisis of the circuit. i mean apply same ac signal at all the terminal with some dc bias or other?

 

[hmsheng]

Re: analog multiplier

You can't apply same AC signal to all the input ports, or else you will get wrong simulation results. If it is quadrature input, that is vin/0°, vin/90°, vin/180°, and vin/270°, you can use four AC sources with differenct initial phase. Or you can use one AC source and a 90° splitter then two balun to ganerate the for input signals.