Electronic systems 5EJ508/9 Tutorial Sheet 1: Op Amps Revised tw 21 1. a) Calcul

Question

Electronic systems 5EJ508/9 Tutorial Sheet 1: Op Amps Revised tw 21 1. a) Calculate the voltage at al amplifier outputs, in terms of the input voltages V, and V, b) What are the two outputs Vr and Ve if V 8mV, and V, E-2mv. 2. In the circuitshown, V1 and V2 are each sinusoidal signals of 5 kHz, and in phase. V has an amplitude of 1.5V, and V2 an amplitude of 2. Assume the "high output of the comparator is 5V, and the "low" output is 0V. a) What is the voltage at Va? b) Sketch clearly the waveforms at Va and Vo (assume the phase angle is zero). Repeat this question by simulating with Multisim.

Explanation / Answer

1. The solution for this question is given below: (Although since the image quality is not very good, the values are best approximated)

Opamp 1 and 2 are unity gain buffers and hence V1=Vx and V2=Vy.

Opamp 3 and 4 are forming Non-inverting amplifier each and applying KCL, their output will be:

V3=Vx(1+9/1)=10Vx and V4=Vy(1+9.5/.5)=20Vy

Opamp 5 and 6 form inverting adders and as in case of inverting adders the output will be

V5=-(40)((V3/10)+(V4/20))=-(40)(Vx+Vy) So, V5=-40(Vx+Vy)

V6=-(80)(V3/20+V4/20)=-(80)(Vx/2+Vy) So, V6=-40(Vx+2Vy)

Finally, Opamp 7 and 8 are inverting amplifiers and hence

V7=-(100/20)V5=-5(-40)(Vx+Vy)=200(Vx+Vy)=1.2 volts

V8=-2(-40)(Vx+2Vy)=80(Vx+2Vy)=0.32 Volts

Related Questions

Navigate

• Browse (All)
• Browse E
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.