CuriousTab
Search
CuriousTab
Home
Aptitude
Computer
C Programming
C# Programming
C++ Programming
Database
Java Programming
Networking
Engineering
Biochemical Engineering
Biochemistry
Biotechnology
Chemical Engineering
Civil Engineering
Computer Science
Digital Electronics
Electrical Engineering
Electronics
Electronics and Communication Engineering
Mechanical Engineering
Microbiology
Technical Drawing
GK
Current Affairs
General Knowledge
Reasoning
Data Interpretation
Logical Reasoning
Non Verbal Reasoning
Verbal Ability
Verbal Reasoning
Exams
AIEEE
Bank Exams
CAT
GATE
IIT JEE
TOEFL
Jobs
Analyst
Bank PO
Database Administrator
IT Trainer
Network Engineer
Project Manager
Software Architect
Discussion
Home
‣
Digital Electronics
‣
Logic Families and Their Characteristics
Comments
Question
What should be done to unused inputs on TTL gates?
Options
A. They should be left disconnected so as not to produce a load on any of the other circuits and to minimize power loading on the voltage source.
B. All unused gates should be connected together and tied to
V
through a 1 k Ω resistor.
C. All unused inputs should be connected to an unused output; this will ensure compatible loading on both the unused inputs and unused outputs.
D. Unused AND and NAND inputs should be tied to
V
CC
through a 1 kΩ resistor; unused OR and NOR inputs should be grounded.
Correct Answer
Unused AND and NAND inputs should be tied to
V
CC
through a 1 kΩ resistor; unused OR and NOR inputs should be grounded.
Logic Families and Their Characteristics problems
Search Results
1. The output current capability of a single 7400 NAND gate when HIGH is called ________.
Options
A. source current
B. sink current
C.
I
OH
D. source current of
I
OH
Show Answer
Scratch Pad
Discuss
Correct Answer: source current
2. Why is a pull-up resistor needed when connecting TTL logic to CMOS logic?
Options
A. to increase the output LOW voltage
B. to decrease the output LOW voltage
C. to increase the output HIGH voltage
D. to decrease the output HIGH voltage
Show Answer
Scratch Pad
Discuss
Correct Answer: to increase the output HIGH voltage
3. Fan-out is determined by taking the ________ result(s) of ________.
Options
A. smaller,
B. larger,
C. smaller,
D. average,
Show Answer
Scratch Pad
Discuss
Correct Answer: smaller,
4. Assume that a particular IC has a supply voltage (
V
cc
) equal to +5 V and
I
CCH
= 10 mA and
I
CCL
= 23 mA. What is the power dissipation for the chip?
Options
A. 50 mW
B. 82.5 mW
C. 115 mW
D. 165 mW
Show Answer
Scratch Pad
Discuss
Correct Answer: 82.5 mW
5. If all inputs to a TTL NAND gate are low, what is the ON, OFF condition of each transistor in the circuit?
Options
A.
Q
1
-ON,
Q
2
-OFF,
Q
3
-ON,
Q
4
-OFF
B.
Q
1
-ON,
Q
2
-ON,
Q
3
-OFF,
Q
4
-OFF
C.
Q
1
-OFF,
Q
2
-OFF,
Q
3
-ON,
Q
4
-ON
D.
Q
1
-OFF,
Q
2
-ON,
Q
3
-OFF,
Q
4
-ON
Show Answer
Scratch Pad
Discuss
Correct Answer:
Q
1
-ON,
Q
2
-OFF,
Q
3
-ON,
Q
4
-OFF
6. The time needed for an output to change from the result of an input change is known as:
Options
A. noise immunity
B. fan-out
C. propagation delay
D. rise time
Show Answer
Scratch Pad
Discuss
Correct Answer: propagation delay
7. Why are the maximum value of
V
OL
and the minimum value of
V
OH
used to determine the noise margin rather than the typical values for these parameters?
Options
A. These are worst-case conditions.
B. These are normal conditions.
C. These are best-case conditions.
D. It doesn't matter what values are used.
Show Answer
Scratch Pad
Discuss
Correct Answer: These are worst-case conditions.
8. The term buffer/driver signifies the ability to provide low output currents to drive light loads.
Options
A. True
B. False
Show Answer
Scratch Pad
Discuss
Correct Answer: False
9. Using the schematic diagram of a TTL NAND gate, determine the state of each transistor (ON or OFF) when all inputs are high.
Options
A.
Q
1
-ON,
Q
2
-OFF,
Q
3
-ON,
Q
4
-OFF
B.
Q
1
-ON,
Q
2
-ON,
Q
3
-OFF,
Q
4
-OFF
C.
Q
1
-OFF,
Q
2
-OFF,
Q
3
-ON,
Q
4
-ON
D.
Q
1
-OFF,
Q
2
-ON,
Q
3
-OFF,
Q
4
-ON
Show Answer
Scratch Pad
Discuss
Correct Answer:
Q
1
-OFF,
Q
2
-ON,
Q
3
-OFF,
Q
4
-ON
10. When is a level-shifter circuit needed in interfacing logic?
Options
A. A level shifter is always needed.
B. A level shifter is never needed.
C. when the supply voltages are the same
D. when the supply voltages are different
Show Answer
Scratch Pad
Discuss
Correct Answer: when the supply voltages are different
Comments
There are no comments.
Enter a new Comment
Save
More in Digital Electronics:
Boolean Algebra and Logic Simplification
Code Converters and Multiplexers
Combinational Logic Analysis
Combinational Logic Circuits
Computers
Counters
Describing Logic Circuits
Digital Arithmetic Operations and Circuits
Digital Concepts
Digital Design
Digital Signal Processing
Digital System Projects Using HDL
Ex-OR and Ex-NOR Gates
Flip-Flops
Integrated-Circuit Logic Families
Integrated Circuit Technologies
Interfacing to the Analog World
Logic Families and Their Characteristics
Logic Gates
Memory and Storage
Microprocessor Fundamentals
MSI Logic Circuits
Multivibrators and 555 Timer
Number Systems and Codes
Programmable Logic Device
Shift Registers
Signals and Switches
The 8051 Microcontroller