Solving for Output Voltage of Op Amp

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The output voltage of the op-amp is calculated using the formula Vo = A(vp - vn), where the inverting input voltage (Vn) is 4mV and the open-loop gain (A) is 2*10^5. With the non-inverting input (Vp) grounded, the calculation yields Vo = -800V, which exceeds the supply voltage limits of ±10V. Therefore, the actual output voltage is limited to -10V due to the power supply constraints. The discussion emphasizes the importance of recognizing that calculated values may be truncated by the op-amp's power supply limits.
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Homework Statement



What is the output voltage for an op amp whose non-inverting input is connected to ground and its inverting-input voltage is 4mv? Assume that the op-amp open-loop gain is 2*10^5 and its supply voltage is Vcc=10V

Homework Equations


Vo= A(vp-vn)


The Attempt at a Solution


The problem gives
Vn= 4mv
A=2*10^5
Vcc=10V
Since it says the non-inverting input is connected to ground, does that mean vp=0?
Vo=2*10^5(0-.004V)
Vo=-800 V
However the answer is suppose to be -10V. What am I doing wrong?
Thanks for helping!
 
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rzn972 said:

Homework Statement



What is the output voltage for an op amp whose non-inverting input is connected to ground and its inverting-input voltage is 4mv? Assume that the op-amp open-loop gain is 2*10^5 and its supply voltage is Vcc=10V

Homework Equations


Vo= A(vp-vn)


The Attempt at a Solution


The problem gives
Vn= 4mv
A=2*10^5
Vcc=10V
Since it says the non-inverting input is connected to ground, does that mean vp=0?
Vo=2*10^5(0-.004V)
Vo=-800 V
However the answer is suppose to be -10V. What am I doing wrong?
Thanks for helping!

Can the output of an op-amp ever exceed its power supply voltages (positive and negative supplies)?
 
Ahh, I see so the max Vo is 10 and min Vo is -10. So is what I did wrong? Do I have the write down that calulated vo= -800 but say the min is -10V.
 
rzn972 said:
Ahh, I see so the max Vo is 10 and min Vo is -10. So is what I did wrong? Do I have the write down that calulated vo= -800 but say the min is -10V.

That's the idea. Do the calculation and then state why in actuality the value will be "truncated" by the limits imposed by the power source.
 
Thank you so much!
 

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