0195136047.pdf

266 ANALOG BUILDING BLOCKS AND OPERATIONAL AMPLIFIERS

−

+

200 Ω

va

100 Ω 500 Ω

100 Ω

vb

v

i 1

i 2

v

vo

Figure P5.4.13

−

+

vi

vo

RF

CF

R 1 C 1

Figure P5.4.16

−

+

vo

vS

R

A

B

i

i

C

+15 V

−15 V

Figure P5.4.18

−

+

vo

vS = 5 V

3 V

C = 0.2 μF

R S

1

A

B

+15 V

−15 V

40 kΩ

Figure P5.4.19

5.4.18Consider the inverting integrator circuit shown in
Figure P5.4.18. LetC= 0. 4 μF andR= 0 .1M.
Sketchvofor a period of 0.5 s after the application
of a constant input of 2 V at thevSterminal.
Assume thatCis discharged at the beginning of
the operation.

5.4.19An integrator with positive voltage on a noninvert-
ing input is shown in Figure P5.4.19. Sketchvofor
60 ms afterShas been opened.

5.4.20Addition and integration can be combined by the
summing integrator circuit shown in Figure
P5.4.20. With the given component values and
input waveforms, sketchvowhenSis opened at
t=0.

5.4.21Refer to the noninverting amplifier circuit of Fig-
ure 5.4.2. LetR 1 =10 k, R 2 =30 k, andvi
be a sinusoidal source with a peak value of 1 V.
Sketch the waveforms ofviandvo.

*5.4.22Develop an analog computer simulation diagram

to solve the differential equation

d^2 y(t)

dt^2

+ 12

dy(t)

dt

+ 5 y(t)= 10

withy( 0 )=2 andy( ̇ 0 )=0.

5.4.23If the solution to the differential equation of Prob-

lem 5.4.22 is to be obtained over 0≤t≤1 ms,

but one wants to expand this over an interval of 1 s,

redraw the analog computer simulation diagram.

5.4.24An integrator as shown in Figure 5.4.18(d) is to be

designed to solve

dy(t)

dt

+ 2000 y(t)= 0

withy(0)=5. IfRiis chosen to be 10 k, findCf.

5.4.25DetermineIin the circuit shown in Figure P5.4.25.