Question

Q 1. An op amp with an open-loop gain of 6 x 105 and Vcc = 10V has an output voltage of 3 V. If the voltage at the inverting input is -luV, what is the magnitude of the noninverting-input voltage? (5 points) Q2. The supply voltage of the op amp in the circuit of Figure 1 is 16 V. If R = 3kN, assign a resistance value to Rf so that the circuit would deliver 75 mW of power to R. (5 points) 50 22 cc = 16 V + 3 V Re RL 4 k923 Figure 1 Q3. For the op-amp circuit shown in Figure 2, (a) Obtain an expression for the current gain G; = illis. (b) If RL = 12k2, choose Rf so that G; = -15. (5 points) Rf LIL RS RL Figure 2 Q4. Design a circuit that can perform the operation ve = 3v1 +4v2 - 503-804, where vi to v4 are input voltage signals. (5 points)

Answer 1

Ao 6x15 vozov, r=-luv rt_2 for op Ame rozton. [ut-w- 3= 6x20 [ut (14)] 3 = 0.6 lut +] Niti z 5 Tuta 4 uv

N+ 34 4kn g2=3ku f = 75mw I given] Shame Vo 7573 No=155 vt - 3V Vox Retakw But Mence 37 = 4 futro tro, + 4 3 15 x 4 R2+4 fit + 4 20 X Rfa 16k u

I tUm is MA ZOV Kchet ist V. ZO Rif voz-kit's]. But ; norzo vo 22 R2 L. RL= - RIUS i t's & 9 ľ=-15, R2=12kw But then - 15 = Rfa 180 12 hifa 18 oku

160 = 36, +42-563-8 V4 Anresting Any inverting Men Rf N vz R2 - fut ht f3 R Re ollo M 43 shf von het ht toku one. Resistance Are Required to, assume without Assuming Reaportance can not design. from AL one Vol Ry 2 from AZ

do2= 23 va 24 Nor = Rt 13 R3 2 from A3 Von & Rit REVO hftRt NO2 Rf RITRE Noit vo vor Noz voz von using O and 2 N3 74 24 Noz ft N К. And ginen Noz 3.0 +442 -5ls Qua

③ and we compare get, Re - 3 R = R = 40 kn ft fz - 2D Rzz ff to = loku 4 fit ²5 = R3= R + R3 - 40 = 8kn क For 4= Rt- 4o-ska 24 therefore Re = toku 12² loku, RIZ 40 kw 3 3 Okw R33 (4=5ku