0195136047.pdf

PROBLEMS 261

5.2.6Determinevo/vifor the circuit shown in Figure
P5.2.6 if the op amps are ideal.

5.2.7Findvo/vifor the circuit shown in Figure P5.2.7 if
the op amp is ideal.

5.2.8Consider the inverting amplifier of Example 5.2.1.
Let a voltmeter be connected (negative voltmeter

terminal at terminal 3) between terminal 3 and

ground to measure voltages accurately between

1 and 10 V. LetRi = 1kandvi =10 V

(dc). Determine the relation between voltage in-

dication andRf, noting that this circuit is an elec-

tronic ohmmeter capable of measuring the value

ofRf.

−

+

vo

vi A

RF 1

R 1

R 2

RF 2

C B −

+

Figure P5.2.4

−

+

va

vo

1

2

Ideal

op amp

R 2

vi

R 3

R 4

R 1 Figure P5.2.5

−

+

vo

vi

1000 Ω

2000 Ω

500 Ω

2000 Ω

−

+

500 Ω

Figure P5.2.6

vo

vi

ii v

1 v 2

R 1

R 2

R 3

+

RS −

i 1

i

Figure P5.2.7