Disclaimer: This review is based on clicker questions that directly relate to the lectures. The exam...

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Disclaimer: This review is based on clicker questions that directly relate to the lectures. The exam will also contain materials from the labs and pre-labs and it will not be multiple-choice. If a topics isn’t covered in today’s class it doesn’t mean that that topics will not be on the exam. (We can’t cover 14 lectures and 7 labs in 50 minutes.)

Transcript of Disclaimer: This review is based on clicker questions that directly relate to the lectures. The exam...

Disclaimer: This review is based on clicker questions that directly relate to the lectures. The exam will also contain materials from the labs and pre-labs and it will not be multiple-choice.

If a topics isn’t covered in today’s class it doesn’t mean that that topics will not be on the exam. (We can’t cover 14 lectures and 7 labs in 50 minutes.)

The input impedance of an ideal ammeter should be

A) zeroB) infinityC) A well defined non-zero value (e.g. 1 or 1k)D) It should provide a constant currentE) should have a shiny red color

The input impedance of an ideal voltmeter should be

A) zero.B) infinity.C) a well defined non-zero value (e.g. 1 or 1k).D) It should provide a constant voltage.E) It should have a bright yellow color.

What is the output impedance of an ideal voltage source?

A) zeroB) infinityC) a well defined resistance, but not zero or

infinity (e.g. 1 or 1k)D) purely complex (i.e. non-zero reactive)E) potato

What is the output impedance Zout of this circuit?

A) R1 + R2

B) R1 – R2

C) R1R2/(R1+R2)

D) R1/(R1+R2)

E) R2/(R1+R2)

V

R1

R2

A

B

What is the output impedance Zout of this circuit?

A) 1/(1/R1+1/R2+1/R3)

B) R1 + R2 + R3

C) R1R2/(R1+R2)

D) R1/(R1+R2)

E) R2/(R1+R2)

V

R1

R2

A

B

R3

A) 0 VB) 2.5 VC) 3.3 VD) 5 VE) 7.5 V

10V

1MW

1 MW

The input impedance of many scopes is 1 MW. What voltage does a scope with 1 MW impedance measure across the lower 1 MW resistor?

Vin Vout

1k

1μF

What is the cut-off frequency fc (aka. the 3dB-frequency f3dB) of this circuit?

A) 159 HzB) 1 kHz C) 6.3 kHzD) 1 MHzE) None of the above

Vin Vout

1k

1μF

What is the gain G of this circuit at the cut-off frequency fc?

A) 0B) 0.5C) 0.7D) 1E) None of the above

Vin Vout

1k

1μF

Draw a bode-plot of this circuit from 1Hz to 1MHz. Draw the vertical axis as “power gain“ (|G|2 in units of dB) and make sure to label the axes correctly (including tick marks).

For the circuit below, it is observed that Vin >> Vout. The shape of Vin is shown at right. Which of the choices best represents Vout? (Note: Vertical axes are not to scale.)

Vout is:

A) –3 V

B) –6 V

C) –9 V

D) –15 V

E) None of the above

Vin = 3 V

What is the voltage at the inverting input?

A)

B)

C)

D)

R

Rf

V1

VoutR

Rf

V2

𝑅𝑓

𝑅+𝑅 𝑓

𝑉 1

𝑅𝑅+𝑅 𝑓

𝑉 1

𝑅𝑓

𝑅+𝑅 𝑓

𝑉 2

𝑅𝑅+𝑅 𝑓

𝑉 2

E) None of the above

Vin

Vout

The open loop gain of this op-amp is 105 and the open loop bandwidth is 10 Hz. What is the bandwidth of a voltage follower made with this op-amp?

A) 10 kHzB) 100 kHzC) 1 MHzD) 10 MHzE) Can not be determined

What is the (approximate) 3dB bandwidth of the circuit shown below if the transition frequency of this transistor is fT = 200 MHz. (Assume that Vin is appropriately biased, i.e. VBE ≥ 0.6V.)

A) 10 kHzB) 100 kHzC) 1 MHzD) 10 MHzE) Can not be determined

+20 V

0 V

Vout

Vin

2 k

100

16

For Vin as shown, rank outputs 1, 2, and 3 according to peak-to-peak amplitude from largest to smallest

A) 1 > 2 > 3

B) 1 > 2 = 3

C) 2 = 3 > 1

D) 2 > 3 > 1

E) 3 > 2 = 1

If you have a signal with ~1V amplitude but you know that your signal cannot deliver more than 1 nA of current, what device would you use to amplify it?

A) A bipolar transistor amplifierB) A J-FET amplifierC) A MOSFET amplifierD) A diode amplifierE) An inverting op-amp amplifier.

A) 0 VB) 4 VC) 5 VD) 6 VE) 10 V

What is Vout with the gate grounded (i.e. Vin = 0V)?

ID

VDS

VGS = 0V

VGS = -0.2V

VGS = -0.6V

VGS = -1.5V

4mA

3mA

2mA

1mA

5V

+10 V1k

Vout

Vin 0 V

A) 1B) 2C) 5D) 10E) 20

What is the maximum gain of this amplifier?

ID

VDS

VGS = 0V

VGS = -0.2V

VGS = -0.6V

VGS = -1.5V

4mA

3mA

2mA

1mA

5V

+10 V1k

Vout

Vin 0 V

20

For a triangular input voltage (from -10V...+10V), the output of circuit 2 is:

A) identical to that of circuit 1B) different; Vout2,pk-pk > Vout1,pk-pk

C) different; Vout2,pk-pk < Vout1,pk-pk

D) different; Vout2,pk-pk = Vout1,pk-pk

circuit 2circuit 1

Vin =  –1 V. No load is attached to the circuit.

Vout is:

A) -2 V

B) +2 V

C) -5 V

D) +5 V

E) None of the above

A bipolar junction transistor (BJT) is

A) a current controlled current amplifier.

B) a voltage controlled current amplifier.

C) a current controlled voltage amplifier.

D) a voltage controlled voltage amplifier.

E) none of the above.

VinVout

You want to make a bode-plot of a piece of wire of length L.At 1 MHz you find that the phase between Vout and Vin is about 90°.

So how long does it take for an electric signal to travel from one end of the wire to the other?

A) No time at all.B) ~ 100 nsC) ~ 250 nsD) ~ 500 nsE) ~ 1 μs

L

N4

A ● 0 =

A) 0B) 1C) AD) A

N5

A ● 1 =

A) 0

B) 1

C) A

D) A

N6

A ● A =

A) 0

B) 1

C) A

D) A

N7

A ● A =

A) 0

B) 1

C) A

D) A

N8

A ● (A+B) =A) 0B) 1C) AD) BE) A ● B

29

For the specified Vin, the following three output signals Vout

were observed.

The graphs above, from left to right, could have been collected using circuits:

A) 3,4,1

B) 3,4,2

C) 1,4,3

D) 3,2,1

E) none of the above

z1 and z2 are two complex numbers with:𝑧1=|𝑧 1|𝑒𝑖 𝜃1 𝑧 2=|𝑧 2|𝑒𝑖 𝜃2, and

A)

B)

C) (

D) (

E) none of the above