Low-pass Filter and Critical Frequency

Name:
Alfredo del junco
Date:
2/22/2014

ET 1410 Final Exam

1. 1. An IC op-amp has ________.

a. two inputs and two outputs

b. one input and two outputs

c. two inputs and one output

d. one input and one output

2. In the common mode, ________.

a. both inputs are grounded

b. the outputs are connected together

c. an identical signal appears on both inputs

d. the output signals are in phase

3. If Av(d) = 3500 and Acm = 0.35, the CMMR is ________.

a. 1225

b. 3500

c. 80dB

d. 90dB

4. A certain op-amp has bias currents of 50 μA and 49.3 μA. The input off-set current is ________.

a. 700 nA

b. 99.3 μA

c. 49.65 μA

d. None of these

5. A certain non-inverting amplifier has a Ri of 1.0 kΩ and an Rf of 100 kΩ. The closed-loop gain is ________.

a. 1001

b. 1000

c. 101

d. 100

For questions 6 through 10, refer to Figure 1.

6. What type of amplifier is shown in Figure 1?

a. Non-inverting amplifier

b. Inverting amplifier

c. Audio amplifier

d. Pulse amplifier

7. Calculate the closed-loop gain.

a. -1

b. -10

c. 2

d. 11

8. Determine the output voltage.

a. -1 V

b. 2 V

c. 11 V

d. -10 V

9. If Ri shorts, the closed-loop voltage gain will ________.

a. increase

b. decrease

c. stay the same

d. become 1

10. If Ri shorts, the input impedance will ________.

a. increase

b. decrease

c. stay the same

d. become 1

11. The BW of an AC amplifier with a lower critical frequency of 1 kHz and an upper critical frequency of 10 kHz is ________.

a. 1 kHz

b. 9 kHz

c. 10 kHz

d. 11 kHz

12. The BW of a DC amplifier with an upper critical frequency of 100kHz is __________.

a. 100kHz

b. unknown

c. infinity

d. 0khz

13. The frequency at which Aol = 1 is called ________.

a. the upper critical frequency

b. the cut-off frequency

c. the