Question

Resistor networks are sometimes used as volume-control circuits. In this application, they are referred to as resistance attenuators or pads. A typical fixed-attenuator pad is shown in the figure. In designing an attenuation pad, the circuit designer will select the values of R1 and R2 so that the ratio of vo/vi and the resistance seen by the input voltage source Rabboth have a specified value. (Figure 1)

Resistors [Ω]
10	100	1.0 k	10 k	100 k	1.0 M
	120	1.2 k	12 k	120 k
15	150	1.5 k	15 k	150 k	1.5 M
	180	1.8 k	18 k	180 k
22	220	2.2 k	22 k	220 k	2.2 M
	270	2.7 k	27 k	270 k
33	330	3.3 k	33 k	330 k	3.3 M
	390	3.9 k	39 k	390 k
47	470	4.7 k	47 k	470 k	4.7 M
	560	5.6 k	56 k	560 k
68	680	6.8 k	68 k	680 k	6.8 M

Problem 3.66 22 | 220 2.2k 22k 220 k 2.2 M Part B 270 2.7 k 27k 270 k 33 330 3.3k33k 330 k 390 3.9 k 39k 390 k 47 470 4.7 k47k 470 k 560 5.6 k56k560 k 68 680 6.8 k68k 680 k 3.3 M Find for RasR r answer in terms of the variables and 2 4.7 M 6.8 M Fiqure of Submit X Incorrect, Try Again: 4 attempts remaining R1 PartC R2 Select the values of R, and R2 so that Rab = RL = 270 Ω and 1, jui = 0.5. Express your answers using three significant figures separated by a comma. Attenuator Pearson se l Pr Copyright © 2019 Pearson Education Inc. All rights reserved. Term olicy permissions Co tact 13 PM 4/20/2019 ere to search 22 220 2.2k 22k 220k 2.2 M Part C 270 2.7 k 27k270 k Select the values of R1 and R2 so that Rab-RL-270 Ω and Vo/Vi-0.5 Express your answers using three significant figures separated by a comma 33 330 3.3 k 33 k 330 k3.3 M 390 3.9 k39 k390 k 47 470 4.7k47 470k4.7 M 560 5.6k56 k 560 k 6.8 M 68 680 6.8 k 68 k 680k n2 Figure

Answer 1

Ri C V2 1 d Ve' givtn Rab: RL

Ri 2 Ri 2V2 R) T2 N2 Voltage across R2 RL Rab 2Rit RL Nin

V2 [RL-2R2 Vo- R14135 Li - 135 135- R 2 2 R2-135-Riこ135-Ri 2 1352R 135 R-R R1, 135 RI -2X 1352-0 Ri--135 J i35, 412メ1352 2. 2 Ri27o, 135 AS, Ri Should be pusitive, Htnce Ri 135 2.

D fom teble RiRL R 3g.8. 치 27口 14.구 1- :/. ErrDY =