I've design the attached bi-polar op amp.
Required Specs:
400<=Ad<=500
Rid >= 20KΩ
fL3db <=100Hz
Voffset <=.01v
Ro <=200Ω
Vop-p>=2v
RL=200Ω
PS=+and - 10v
(The beta for the 2N2222 in my pspice model is 255)
I've inputed a 5mv peak to peak signal and get 2.47 v out p-p which is a gain of 494, which meets spec. The gain of each stage does not match what I calculate they should be.
Adiffcalc=71
Adiffpspice=34
Againcalc=36
Againpspice=15.9
Atotcalc=2597
Atotspice=594
What formulas should I use to calculated the stage gains.
Second question, I picked R12 to be 680Ω so I would have 15mA collector current, I calculate Rout to be 1.7Ω, is this correct and is it a reasonable value?
I had asked a similar question a few weeks ago and didn't really understand the answer. How do I calculate the maximum peal to peak output voltage that this circuit can generate. I then assume the maximum input voltage would just be the max output divided by the gain?
Thanks for your help.
Required Specs:
400<=Ad<=500
Rid >= 20KΩ
fL3db <=100Hz
Voffset <=.01v
Ro <=200Ω
Vop-p>=2v
RL=200Ω
PS=+and - 10v
(The beta for the 2N2222 in my pspice model is 255)
I've inputed a 5mv peak to peak signal and get 2.47 v out p-p which is a gain of 494, which meets spec. The gain of each stage does not match what I calculate they should be.
Adiffcalc=71
Adiffpspice=34
Againcalc=36
Againpspice=15.9
Atotcalc=2597
Atotspice=594
What formulas should I use to calculated the stage gains.
Second question, I picked R12 to be 680Ω so I would have 15mA collector current, I calculate Rout to be 1.7Ω, is this correct and is it a reasonable value?
I had asked a similar question a few weeks ago and didn't really understand the answer. How do I calculate the maximum peal to peak output voltage that this circuit can generate. I then assume the maximum input voltage would just be the max output divided by the gain?
Thanks for your help.
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