Deck 6: Basic Op-Amp Circuits, Special-Purpose Op-Amp Circuits, the Operational Amplifier, Transistors and Applications

Question 1

Figure 20-1

-Refer to Figure 20-1 (a). If R₁ = R₂ = 30 k? and the closed loop gain is 450, the value of the external gain-setting resistor R_G is:

A) 13.4 ?.
B) 134 ?.
C) 134 k?.
D) none of the above.

Answer 1

134 ?.

Question 2

The voltage gain of an OTA can be calculated using the formula:

A) A_V= g_mR_L.
B) A_V= 2 Rf/R_i.
C) A_V= R_f/R_i.
D) A_V= (R_f/R_{i) +} 1.

Answer 2

A_V= g_mR_L.

Question 3

Figure 19-2

-If the inputs are 1.2 V, -0.5 V and 2.4 V in Figure 19-2(b), what is the output voltage?

A) -4.1 V
B) -6.2 V
C) 6.2 V
D) 13 V

Answer 3

-6.2 V

Question 4

Figure 19-3

-If V_IN= 70 V_P in Figure 19-3, the output voltage at f_CO equals ________.

A) 49.5 V_P
B) 0 V_P
C) 13 V_P
D) 44.2 V_P

Question 5

The output of an op-amp differentiator depends on the values of ________ and ________.

A) R_IN, C_F
B) C_IN, C_F
C) C_IN, R_F
D) R_IN, R_F

Question 6

Figure 18-1

-If R_f = 1.2 M? and A_V = 120 in Figure 18-1(c), R_i equals ________.

A) 100 k?
B) 120 ?
C) 1 k?
D) 10 k?

Question 7

Figure 18-1

-V_RF equals ________ in Figure 18-1(c).

A) V_CC
B) V_RI
C) V_IN
D) V_OUT

Question 8

Figure 18-1

-If R_f = 150 k? and R_i = 2.2 k? in Figure 18-1(c), the voltage gain equals ________.

A) -69.2
B) -68.2
C) -1
D) infinite

Question 9

Figure 18-1

-If R_f = 1.2 M? and R_i = 47 k? in Figure 18-1(b), the voltage gain equals ________.

A) 25
B) 26
C) 26.5
D) 25.5

Question 10

Figure 18-1

-If R_f= 100 k? and A_V = (-833) in Figure 18-1(c), R_i equals ________.

A) 10 k?
B) 1 k?
C) 100 k?
D) 120 ?

Question 11

Figure 18-1

-If R_f = 5 k? and R_i = 10 k? in Figure 18-1(c), the voltage gain equals ________.

A) -5
B) -2
C) 0
D) -0.5

Question 12

Voltage gain can be found by A_V = V_IN ÷ V_OUT

Question 13

On transistor spec sheet, the key difference between ?_DC and ?_DC is that:

A) ?_DC represents I_C/I_B; ?_DC represents I_C/I_E.
B) ?_DC represents I_E/I_C; ?_DC represents I_B/I_C.
C) ?_DC represents I_E/I_C; ?_DC represents I_C/I_E.
D) ?_DC represents I_C/I_B; ?_DC represents I_B/I_c.