Hello Folks. I am trying to solve an amplifier problem.

I believe the DC gain of the circuit below is ( -10k ÷ 1k). Can you please let me know if that is correct?

I also think the AC gain would be [ (- 10k)(1k - 1000j) / (1k) (-1000j) ].

Did I figure out the DC and AC gains correctly?
Thank You

p.s. I am calculating the closed loop gain here, keeping in mind that this is an inverting amplifier.

 

Why did you leave capacitor out?

 

Why did you leave capacitor out?

Cause the problem is asking me to find the DC and AC gains. i figured in the DC gain scenario the capacitor is nothing more than an open wire.

 

I believe your DC is correct. DC will not interrupt, the capacitor will fully charge and, in DC environment, will act as open circuit. Therefore the gain is determine my only R1 and R2, like you have done.

 

I believe your DC is correct. DC will not interrupt, the capacitor will fully charge and, in DC environment, will act as open circuit. Therefore the gain is determine my only R1 and R2, like you have done.

What about my AC gain? Did i figure out the AC Gain correctly? Can you please comment on my AC gain?

 

yes you did the ac correct, but it might be better expressed as G = (R1/R2)(s + 1/R2C2) where s = jw.

 

yes you did the ac correct, but it might be better expressed as G = (R1/R2)(s + 1/R2C2) where s = jw.

I think w might be giving to OP. They just did not tell us what it is. That would explain the -1000j Ohm value of the capacitor. There is no need to go to s domain because w does not change, it is constant and is known to OP.

 

In the s domain representation it is simple to graph the result in a Bode plot form so further analysis can be done visually. A matter of preference I think.

 

No schematic?