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Poster has been reminded to post schoolwork in the Homework Help forums (moved from EE)
Hi everybody!
This is my first post as I am needing some help in a question I am struggling with. Not looking for answers, just some guidance in the right direction.
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I need to calculate the unknown, highlighted, voltages on the op amp circuits (attached).
Assume all opamps are ideal
See below
I have done the following so far:
a) Inverting
A=Rf/Ri =(100)/10=10
Vi =I1*R1 =0.00001*100000=1 V
Vo=(Rf/Ri )*Vi
Vo =1*10
Vo =10 V
b) Summing
Vo=(Rf/R_1 V_1+Rf/R_2 V_2 )
2=(Rf/R_1 1+Rf/(R/2) V_2 )
c) Noninverting
V1 =V2
V1 =100 mV
V2 =100 mV
d) Current to Voltage
Vo=I1*Rf
Vo =0.0002*10000=2
Vo =2 V
I am struggling the (b). I cant see how to calculate given only one value, and also with (c)
Many thanks in advance, happy to discuss the methods.
Joel
This is my first post as I am needing some help in a question I am struggling with. Not looking for answers, just some guidance in the right direction.
Homework Statement
[/B]
I need to calculate the unknown, highlighted, voltages on the op amp circuits (attached).
Assume all opamps are ideal
Homework Equations
See below
The Attempt at a Solution
I have done the following so far:
a) Inverting
A=Rf/Ri =(100)/10=10
Vi =I1*R1 =0.00001*100000=1 V
Vo=(Rf/Ri )*Vi
Vo =1*10
Vo =10 V
b) Summing
Vo=(Rf/R_1 V_1+Rf/R_2 V_2 )
2=(Rf/R_1 1+Rf/(R/2) V_2 )
c) Noninverting
V1 =V2
V1 =100 mV
V2 =100 mV
d) Current to Voltage
Vo=I1*Rf
Vo =0.0002*10000=2
Vo =2 V
I am struggling the (b). I cant see how to calculate given only one value, and also with (c)
Many thanks in advance, happy to discuss the methods.
Joel
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