BillQ
Junior Member level 1
For an amplifier simulation
I run a DC sweep analysis and got the DC transfer curve Vout vs. Vin, then I can calculate the gain A from the slope of the transfer curve
I also run an AC analysis and plot directly the gainB=Vout/Vin.
For B at very low frequency, the amplifier should also operate at near DC condition. But the two values A and B(f~0) are completely different
I am wondering these two are just completely different analysis, AC refers to the small signal gain, but DC refers to the large signal gain. So maybe I should no compare them at all. Is my understanding correct?
Added after 40 seconds:
Just now I also checked the ac output voltage in magnitude.
Its voltage is even several KV, but my supply voltage is limited to 3.3V
Does it mean that I don't need to care about the AC output magnitude, but only the resulted ratio Vout/Vin in the AC simulation
I run a DC sweep analysis and got the DC transfer curve Vout vs. Vin, then I can calculate the gain A from the slope of the transfer curve
I also run an AC analysis and plot directly the gainB=Vout/Vin.
For B at very low frequency, the amplifier should also operate at near DC condition. But the two values A and B(f~0) are completely different
I am wondering these two are just completely different analysis, AC refers to the small signal gain, but DC refers to the large signal gain. So maybe I should no compare them at all. Is my understanding correct?
Added after 40 seconds:
Just now I also checked the ac output voltage in magnitude.
Its voltage is even several KV, but my supply voltage is limited to 3.3V
Does it mean that I don't need to care about the AC output magnitude, but only the resulted ratio Vout/Vin in the AC simulation