Hey again...i'm doing an exercise involving only one ideal opamp, and the goal is to find the current i0 (across the RL resistor), and show that the expression of that current is function of all resistors except RL and of the voltage Vref.
My aproach to this is to define a current across R1 doing Vref/R1 bearing in mind that the voltage on the -ve terminal of the opamp is 0. But then it strikes me: "well, if the expression for the current i0 doesnt depend on RL, there has to be a voltage on the +ve terminal too, just so we can apply KCL in the node between R2 and RL"... Well, i dont know if im thinking right or not, what i know is that im running around in circles with equations that dont make any sense.
Said that, i must confess (although this exercise look very easy to do) i need some guidance in this.
Thanks in advance, and im sorry if my doubts seem noob in some way, but the way my professors teach these elementar notions is (unfortunately) inversely proportional to the difficulty of some of the assingments they ask us to do.
P.S: Btw, How would i do to calculate the voltage Va, function of all the resistors in the circuit (including RL) and Vref??
Cheers
My aproach to this is to define a current across R1 doing Vref/R1 bearing in mind that the voltage on the -ve terminal of the opamp is 0. But then it strikes me: "well, if the expression for the current i0 doesnt depend on RL, there has to be a voltage on the +ve terminal too, just so we can apply KCL in the node between R2 and RL"... Well, i dont know if im thinking right or not, what i know is that im running around in circles with equations that dont make any sense.
Said that, i must confess (although this exercise look very easy to do) i need some guidance in this.
Thanks in advance, and im sorry if my doubts seem noob in some way, but the way my professors teach these elementar notions is (unfortunately) inversely proportional to the difficulty of some of the assingments they ask us to do.
P.S: Btw, How would i do to calculate the voltage Va, function of all the resistors in the circuit (including RL) and Vref??
Cheers
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