Question

The input to the below op-amp circuit is the source voltage vi(t) and the response is the voltage across Rư, vo(t). Design this circuit to satisfy the following two specifications: (a) The phase shift at w = 1000 rad/s is 225 degree. (b) The gain at high frequencies is 10. Ri C = 0.1 uF vilo o Rız volt)

Answer 1

circuit as. Here . we have Ric given R2 R2 C=O-INF & volt) we know that in virnucel ground concept v=ut here, u= ut- ov. Now applying KCL at o, or - vit ) & 6-volt) = 0 R2 = Pit loc - - JR, WC jriwc of I Rearranging we have Volt) o it) - jWCR 2 It; WER,

ia here, Shift at w=10oo rad bec ix 225 . phase from ean (9) we can see phose shift in, d= -90°- tan ocR, +225 can also be written an, -138 Now here, ago-tan WR, = -135 i tan IwCP, - 45° and C=0.I Mf= 10 +F. and WC R₂ = 1. putting the values, w = 1ooorad laec we have, 103 x 10 7 XR1 = 1 con . RI=2042= LOKR. Here we can find ja loks. Again here from equanon a we See gain in M= WcRa Sito ² c ² Rp we can see that manimum gain happen when co- oo. Since then, can

m= R20 at w= 0, m= R26 Ric Ri since given m=10., : R210. we have calculated Rg-golz in previos part and hence, R = IOR = 10x Lolch = 100 kr Hence we should have R2-gooka. Now we have final circuitos, loks Q-IMF sooka vist - Volt)