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Test
Your EQ #146— Answer
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Answer
4
The
output of the first opamp is
VO1 = (1 + R1/R2) V1 [1]
Assuming the differential input voltage Vd = 0 (i.e. V–
= V+) and applying KCL (Kirchoff's Current Law) at the
inverting terminal of the second opamp, we get
(VO1 – V2)/R1 = (V2 – VOUT)/R2
Rearranging
the above equation and using equation [1] to substitute
for
VO1,
VOUT = (1+ R2/R1)(V2 – V1)
Therefore,
the circuit is a subtractor.
Contributor:
Naveen PN
Published: September-2002
