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# configuration of this circuit elements with mosfets

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#### electronicman26

##### Full Member level 2
i want to make this circuit elements only with mosfet transistors, please help me how I can do this

Is it correct structure for CCCS with Mosfet?

use this circuit config. It fits better in your circuit

electronicman26

### electronicman26

Points: 2
use this circuit config. It fits better in your circuit
Its a two-port circuit and I want to replace 2 CCCS with Mosfet circuits, but I dont know how I can do it , that two-port remain

How is it possible to realize this two-port circuit?

my thought was to replace each of your Ai1 and Ai2 with the circuit i have given.

Of course the fact that the whole thing is being supplied with a current source creates some problems, so maybe even THAT can be replaced with a 3rd instance of my circuit.

choose an appropriate Vdd etc. The dotted wire of my circuit is what sources the current.

isn't that what you want ?

Oh wait.... your sources Ai1 and Ai2 are functions of i1 and i2 !!!

sorry .... i can't help any further in this homework excercise

let me describe my goal clearly
it is a two-port circuit, and now i want to realize two current controlled current source with circuit elements (preferably with Mosfets), but I dont know how I do this that the two-port remains

How is it possible to realize this two-port circuit?

which 2-port circuit are you referring to ? please post it.

which 2-port circuit are you referring to ? please post it.
Hello
this 2-port:

unable to understand your diagram. What is current Io ? Why would V1 <> V2 ? Looks like a 1-port to me.
sorry.. i cannot help

unable to understand your diagram. What is current Io ? Why would V1 <> V2 ? Looks like a 1-port to me.
sorry.. i cannot help
Io is the current between R1 and R2 (it is clear) , V1 is equal to V2, but what is your problem?

so is R1 shorted to R2 at that point ?

so is R1 shorted to R2 at that point ?
yes as shown in the schematic

I must admit it is confusing. With so many things shorted out there is not much left. The input voltage = the output voltage so it hasn't two ports. The current sources are shorted so can be replaced by a single one. The resistors are shorted so can be replaced by one. You are left with two pins, a current source and a resistor.

I think the wider problem needs to be explained - the question as it stands seems meaningless.

Keith

I must admit it is confusing. With so many things shorted out there is not much left. The input voltage = the output voltage so it hasn't two ports. The current sources are shorted so can be replaced by a single one. The resistors are shorted so can be replaced by one. You are left with two pins, a current source and a resistor.

I think the wider problem needs to be explained - the question as it stands seems meaningless.

Keith
I think current sources cant be replaced by a single one beacuse they are CCCS and not independent, and resistors cant be replaced by one beacuse the Io current be lost
I think in circuit teory it is possible that in 2-port circuits V1=V2, however it isnt important for me to prove that this circuit is 2-port or 1-port, it is a circuit schematic and I want to make it with circuit elements

I think the wider problem needs to be explained - the question as it stands seems meaningless.
The circuit uses at least circuit elements that need explanation. To represent it in common network syntax, the current sense elements have to be replaced by (possibly very small) resistors. The operation already clarifies that the circuit is actually a two-port.

For a MOSFET implementation with current mirrors, the acceptable voltage drop of current sense elements need to be specified.

Most likely it's a homework problem with a certain context (preceeding problems, lecture script, text book etc.). Without knowing the context, it's difficult to guess the intended solution method.

I was ignoring the fact that input and output currents can be different which would make it two port - sorry.

Keith

Most likely it's a homework problem with a certain context (preceeding problems, lecture script, text book etc.). Without knowing the context, it's difficult to guess the intended solution method.
It is an example for two-port chapter of circuit teory, now I want to make CCCS with mosfet and replace CCCS, and now it is my problem that how can I do this?

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I don't see how simple current mirrors can be used instead of a (more or less ideal) CCCS. I would try with a combination of fully differential OTAs.

I don't see how simple current mirrors can be used instead of a (more or less ideal) CCCS. I would try with a combination of fully differential OTAs.
OK, I would be glad you help me to make this circuits with circuit elements, how I replace the CCCS with OTA?

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