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- Question
Two 4-bit binary numbers (1011 and 1111) are applied to a 4-bit parallel adder. The carry input is 1. What are the values for the sum and carry output?
Options- A. ∑4∑3∑2∑1 = 0111, Cout = 0
- B. ∑4∑3∑2∑1 = 1111, Cout = 1
- C. ∑4∑3∑2∑1 = 1011, Cout = 1
- D. ∑4∑3∑2∑1 = 1100, Cout = 1
- Correct Answer
- ∑4∑3∑2∑1 = 1011, Cout = 1
- 1. The hexadecimal equivalent of 15,536 is ________.
Options- A. 3CB0
- B. 3C66
- C. 63C0
- D. 6300 Discuss
- 2. The two digits in the binary number system are ___ and ___.
Options- A. 1, 2
- B. H, L
- C. T, F
- D. 0, 1 Discuss
- 3. The GAL16V8 has:
Options- A. 16 dedicated inputs.
- B. 8 special function pins.
- C. 8 pins that are used as inputs or outputs.
- D. All of the above Discuss
- 4. The output of an AND gate is LOW ________.
Options- A. all the time
- B. when any input is LOW
- C. when any input is HIGH
- D. when all inputs are HIGH Discuss
- 5. The Boolean expression for a 3-input AND gate is ________.
Options- A. X = AB
- B. X = ABC
- C. X = A + B + C
- D. X = AB + C Discuss
- 6. An edge-triggered flip-flop can change states only when ________.
Options- A. the trigger is HIGH
- B. the D input is HIGH
- C. the trigger is LOW
- D. the trigger input changes levels Discuss
- 7. Why is the fan-out of CMOS gates frequency dependent?
Options- A. Each CMOS input gate has a specific propagation time and this limits the number of different gates that can be connected to the output of a CMOS gate.
- B. When the frequency reaches the critical value, the gate will only be capable of delivering 70% of the normal output voltage and consequently the output power will be one-half of normal; this defines the upper operating frequency.
- C. The higher the number of gates attached to the output, the more frequently they will have to be serviced, thus reducing the frequency at which each will be serviced with an input signal.
- D. The input gates of the FETs are predominantly capacitive, and as the signal frequency increases the capacitive loading also increases, thereby limiting the number of loads that may be attached to the output of the driving gate. Discuss
- 8. A gate can drive a number of load gate inputs up to its specified ________.
Options- A. supply voltage
- B. noise margin
- C. fan-in
- D. fan-out Discuss
- 9. The 74139 dual four-line demultiplexer functions as a decoder if ________.
Options- A. the
line is grounded - B. data input is on the line
- C. data input is on the A0 line
- D. the A0 line is grounded Discuss
- 10. A complete alphanumeric code would include 26 lowercase letters, 26 uppercase letters, 10 numeric digits, 7 punctuation marks, and anywhere from ________ to ________ other characters.
Options- A. 5, 10
- B. 10, 15
- C. 10, 20
- D. 20, 40 Discuss
More questions
Correct Answer: 3CB0
Correct Answer: 0, 1
Correct Answer: 8 pins that are used as inputs or outputs.
Correct Answer: when any input is LOW
Correct Answer: X = ABC
Correct Answer: the trigger input changes levels
Correct Answer: The input gates of the FETs are predominantly capacitive, and as the signal frequency increases the capacitive loading also increases, thereby limiting the number of loads that may be attached to the output of the driving gate.
Correct Answer: fan-out
Correct Answer: the
line is grounded Correct Answer: 20, 40
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