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See image. I have tried to decipher what i think is correct. I've done it in two parts, marked in red and blue and then added the two currents at node P to find Vout. Need to know if i am correct. Also for the part marked in red. Do you consider the op amp or do you ignore it since it's voltage is zero and use it as a series circuit? And where do you connect the battery in this circuit? Must you analyse the circuit at 0.1, 0 and -0.1? Any and all help is much appreciated. Thanks.

http://i1362.photobucket.com/albums/r687/JasonMcG1/Circuit_2_zps0f2325ee.jpg

Jason M

First, draw your circuit in CL and run a DC Solver simulation on it, showing you the various voltages and, if you want, currents around the circuit.

The you can set up a 0.1V pk-pk 1kHz sinewave at Vin and run a Time Domain Simulation on it.

That will show you what the circuit does and give you some insight into how the maths works that describes it. Then you can sanity check your sums against the simulation.

Assuming CL converges OK (not always a given) then what it shows you will be correct and if your sums disagree then you have made an error in your sums.

Second, take more care with your arithmetic and Ohms Law. For example, in red at the top left of your circuit: 9V across 10k is 0.9mA not 90mA!

You ask: "Do you consider the op amp or do you ignore it since it's voltage is zero and use it as a series circuit?"

There are 4 opamps in the circuit. Please clarify your question.

You ask: "where do you connect the battery in this circuit?"

Read the circuit. There are two batteries and exactly where they are connected to clearly shown in the diagram.

You ask: "Must you analyse the circuit at 0.1, 0 and -0.1?"

The assignment clearly states: "determine Vout with -0.1V dc at Vin"

Note that the supply pins on CL opamps are not polarity sensitive. You can set either supply pin to any voltage and the other to any other voltage and the model will correctly pick up which is the highest voltage supply limit and which is the lowest.

So if you set one pin to -5V and the other to +5V then the model will run with a high output limit of +5V and a low limit of -5V, irrespective of which supply pin is connected to the +ve and the -ve supply voltage.

In general, if you set either pin to Va and the other to Vb where Va > Vb then the model will operate with a high limit of Va and a low limit of Vb.

This is true even if Va > Vb > 0 or 0 > Va > Vb.

Try editing the supply pin voltages.

Simulate > Time Domain > Run Time-Domain Simulation

https://www.circuitlab.com/circuit/75e48w/opamp-supply-pins-01/

http://i1362.photobucket.com/albums/...psac535a8d.jpg

So I've calculated Vout to be 23.9V.

Need help with what to do in part ii..

@JasonMcG,

i) Your link is broken

ii) Sorry but until you have drawn and attempted to simulate your circuit in CL as described above and you have made it unlisted or publically available, you are unlikely to get any further help in this forum.

How do i make the circuit publically available?

https://www.circuitlab.com/circuit/xys87p/screenshot/540x405/

i) Your link is broken.

ii) "How do i make the circuit publically available?"

https://www.circuitlab.com/blog/2012/06/07/unlisted-circuits-easier-sharing-of-schematics/