21. If the specified linear measuring function is Vout = 1.4g – 4.35 V, the input voltage values of the differential op-amp circuit must be (a) V, = 3.11 V and V2 = V (c) Vị = -3.11 V and V2 = V½ (b) V, = V and V½ =- 4.35 V (d) V1 = – 4.35 V and V2 = V

Discuss what a difference amp is, give equations and details, what is a single-ended and differential signal, what is a 4-20 mA signal, what is common-mode noise and why is a difference amp used?

A certain op-amp has two internal amplifier stages with the following gains and critical frequencies; Av1 = 50 dB, Av2 = 25 dB, fc1 = 1500 Hz, and fc2 = 3000 Hz. Determine the open loop midrange gain in decibels and total phase lag when f = fc1....

(a) An operational amplifier shown in Figure 1. Sketch the real circuit model of the amplifier. As a real op-amp it has the following specifications: Input resistance Output resistance Open-loop gain Rin=1MQ Ro=2002 Ao=100,000 190KQ Figure. 1

a) For an opamp, the input bias current Ib =60uA and the input offset current lio= 10uA Find the input base currents and In b) Design an opamp circuit with the following output: Vo = - Vin/4 + 2 For the circuit given below Given :Vin-0.2V, Vsat= 12V D Identify (name) the circuit (stage 1 and 2) O Find the output voltage Vo and the current through the load 4ka 0 Find Vo if the resistor 2kn opens 10 k Stage Stage 2 Vo Vin

The midrange open-loop gain, "Aol(mid)" of a certain op-amp is 80,000. If the open-loop critical frequency is 1 kHz, what is the open-loop gain, "Aol" at each of the following frequencies? (a)100 Hz (b)  1 MHz

3R The op-amp will only slightly amplify signals: a.when the supply voltages are less than +/- 25V b.that are common on both the inputs c.that are different on both the inputs d.when the supply voltages are more than +/- 25V

Assuming an ideal· op-amp's saturation voltage- UsSAT = +15V. For the- circuit in Figure · if u = 3V, the output voltage of op-amp is (404) i 10

+Vcc Vin VI Vo Vref VN -Vcc Ry RxL Figure Q.A2(e). Inverting Schmitt-trigger circuit. (ii) The operational-amplifier (op-amp) of the inverting Schmitt-trigger in Figure Q.A2(e) has saturation voltages of +Vsat = +11 V and -Vsat = -11 V. The voltage divider circuit has the relationship of Rx = 2RY with the value of RY being 100 kn. Using the relationships derived above: (a) Calculate the values of the upper threshold point (UTP or Vi*), lower threshold point (LTP or Vr). (b) Now, sketch the input-output characteristic of the inverting Schmitt- trigger. Clearly label axes, the threshold voltages and the saturation voltages in your sketch.

Answer the following questions a) What assumption do we make for an ideal op - amp? b) Explain what slew rate is why it is important characteristic for an op amp.