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1. A settable flip-flop's normal starting state when power is first applied to a circuit is always the ________ state.

Options

A : reset

B : set

C : toggle

D : dual

2. What is the difference between setup time and hold time?

Options

A : Setup time occurs after the active clock edge, hold time occurs before the active clock edge.

B : Setup time occurs before the active clock edge, hold time occurs after the active clock edge.

C : Setup time and hold time both occur at the active clock edge.

D :

3. Which of the following circuit parameters would be most likely to limit the maximum operating frequency of a flip-flop?

Options

A : setup and hold time

B : clock pulse HIGH and LOW time

C : propagation delay time

D : clock transition time

4. Is the propagation delay from the clock to the output for the 7476 the same as the delay from the set or reset to the output?

Options

A : yes

B : no

C :

D :

5. Decoupling capacitors should be tied from V CC on one device to ground on a different device.

Options

A : True

B : False

C :

D :

6. The purpose of a pull-up resistor is to keep a terminal at a ________ level when it would normally be at a ________ level.

Options

A : LOW, float

B : HIGH, float

C : clock, float

D : pulsed, float

7. Why does the data sheet for the 7476 only give a minimum value for the clock pulse width (both HIGH and LOW)?

Options

A : nominal value

B : best-case condition

C : worst-case condition

D :

8. A Schmitt trigger:

Options

A : has two trip points

B : is a zero crossing detector

C : has positive feedback

D : has two trip points and positive feedback

9. A Schmitt trigger has V T + = 2.0 V and V T ? = 1.2 V. What is the hysteresis voltage of the Schmitt trigger?

Options

A : 0.4 volt

B : 0.6 volt

C : 0.8 volt

D : 1.2 volts

10. Why should a LED be pulled LOW from a logic gate rather than pulled HIGH?

Options

A : LOW-level current is smaller.

B : LOW-level current is larger.

C : HIGH-level current is larger.

D : LOW-level current is smaller and HIGH-level current is larger.

1. Define a race condition for a flip-flop.

Options

A : The inputs to a trigger device are changing slightly before the active trigger edge.

B : The inputs to a trigger device are changing slightly after the active trigger edge.

C : The inputs to a trigger device are changing at the same time as the active trigger edge.

D :

2. Which of the following flip-flop timing parameters indicates the time it takes a Q output to respond to a C p input?

Options

A : t s , t h

B : t PHL , t PLH

C : t w (L), t w (H)

D : f max

3. The main concern when using a pull-down resistor is:

Options

A : the low power dissipation of the resistor

B : it will keep a floating terminal LOW

C : the high power dissipation of the resistor

D : it will cause false triggering

4. What is the major advantage of the J-K flip-flop over the S-R flip-flop?

Options

A : The J-K flip-flop is much faster.

B : The J-K flip-flop does not have propagation delay problems.

C : The J-K flip-flop has a toggle state.

D : The J-K flip-flop has two outputs.

5. The ________ circuit overcomes the problem of switching caused by jitter on the inputs.

Options

A : astable multivibrator

B : monostable multivibrator

C : bistable multivibrator

D : Schmitt trigger

6. The output of a standard TTL NAND gate is used to pull an LED indicator LOW. The LED is in series with a 470-? resistor. What is the current in the circuit when the LED is on?

Options

A : 7.02 mA

B : 8.51 mA

C : 10.63 mA

D : 5.32 mA

7. One example for the use of a Schmitt trigger is as a(n):

Options

A : switch debouncer

B : racer

C : astable oscillator

D : transition pulse generator

8. When the inputs to a flip-flop are changing at the same time that the active trigger edge of the input clock is making its transition, this condition is called:

Options

A : racing

B : toggling

C : slave loading

D : pulse timing

9. A series RC circuit can be used to generate a power-up (automatic) reset signal.

Options

A : True

B : False

C :

D :

10. A Schmitt trigger has a positive feedback circuit and experiences a phenomenon called hysteresis .

Options

A : True

B : False

C :

D :

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