Competitive Examinations, Scholarships
Hardware design interview questions
Hardware design interview questions
Give two ways of converting a two input NAND gate to an inverter
Given a circuit, draw its exact timing response. (I was given a Pseudo Random Signal Generator; you can expect any sequential ckt)
What are set up time & hold time constraints? What do they signify? Which one is critical for estimating maximum clock frequency of a circuit?
Give a circuit to divide frequency of clock cycle by two
Design a divide-by-3 sequential circuit with 50% duty circle. (Hint: Double the Clock)
Suppose you have a combinational circuit between two registers driven by a clock. What will you do if the
delay of the combinational circuit is greater than your clock signal? (You can’t resize the combinational circuit transistors) (more…)
VLSI and hardware engineering interview questions
VLSI and hardware engineering interview questions
Explain why & how a MOSFET works
Draw Vds-Ids curve for a MOSFET. Now, show how this curve changes (a) with increasing Vgs (b) with increasing transistor width © considering Channel Length Modulation
Explain the various MOSFET Capacitances & their significance
Draw a CMOS Inverter. Explain its transfer characteristics
Explain sizing of the inverter
How do you size NMOS and PMOS transistors to increase the threshold voltage?
What is Noise Margin? Explain the procedure to determine Noise Margin
Give the expression for CMOS switching power dissipation
What is Body Effect?
Describe the various effects of scaling (more…)
Embedded systems interview questions
Embedded systems interview questions
Can structures be passed to the functions by value?
Why cannot arrays be passed by values to functions?
Advantages and disadvantages of using macro and inline functions?
What happens when recursion functions are declared inline?
Scope of static variables?
Difference between object oriented and object based languages?
Multiple inheritance - objects contain howmany multiply inherited ancestor? (more…)
Computer architecture and design interview questions
Computer architecture and design interview questions
What is pipelining?
What are the five stages in a DLX pipeline?
For a pipeline with ‘n’ stages, what’s the ideal throughput? What prevents us from achieving this ideal throughput?
What are the different hazards? How do you avoid them?
Instead of just 5-8 pipe stages why not have, say, a pipeline with 50 pipe stages?
What are Branch Prediction and Branch Target Buffers?
How do you handle precise exceptions or interrupts?
What is a cache?
What’s the difference between Write-Through and Write-Back Caches? Explain advantages and disadvantages of each.
Cache Size is 64KB, Block size is 32B and the cache is Two-Way Set Associative. For a 32-bit physical address, give the division between Block Offset, Index and Tag. (more…)
RF and radio engineering interview questions
RF and radio engineering interview questions
What’s a PCB? Printed Circuit Board.
Name some band definitions. L-Band - 1-2 GHz, S-Band - 2-4 GHz, C-Band - 4-8 GHz, X-Band - 8-12 GHz, Ku-Band - 12-18 GHz.
What’s the definition of gain? The signal going into the device is smaller than the signal going out.
What’s a definition of an amplifier? It’s a device that exhibits gain.
Insertion loss? The signal going in is greater than the signal that’s coming out.
Thermal impedance? A measure of how hot the device gets with varying electrical input.
What’s the relation between dB and change of signal? +3 dB is 2 times bigger, +10 dB is 10 times bigger.
What’s an octave? The bandwidth characterized by higher band being twice as much as lower band (100-200 MHz). (more…)
Hardware and software design questions
Hardware and software design questions
Asked by a famous microprocessor manufacturer.
What is Finite Automata
What is a Turing machine?
How many processors are there in a pentium microprocessor? In Sparc?
Difference between RISC and CISC
Is RISC always fast?
What is a real time system?
Name some real time OSs.
Is DOS a real time OS?
What is a kernel,shell?
What is binary search, traversal, hashing?
Write a code to count the no. of 1’s in a binary representation of a number. (more…)
Telecommunications interview questions
Telecommunications interview questions
A well-known telecommunications company uses this pop quiz for oral and written examinations of applicants for engineering positions.
1. A 2MB PCM(pulse code modulation) has…
a) 32 channels
b) 30 voice channels & 1 signaling channel.
c) 31 voice channels & 1 signaling channel.
d) 32 channels out of which 30 voice channels, 1 signaling channel, & 1 synchronization channel.
Ans: c
2. Time taken for 1 satellite hop in voice communication is…
a) 1/2 second
b) 1 seconds
c) 4 seconds
d) 2 seconds
Ans: (a)
3. Max number of satellite hops allowed in voice communication is:
a) only one
b) more han one
c) two hops
d) four hops
Ans: ©
4. What is the maximal decimal number that can be accommodated in a byte?
a) 128
b) 256
c) 255
d) 512
Ans: ©
5. Conditional results after execution of an instruction in a micro processor is stored in…
a) register
b) accumulator
c) flag register
d) flag register part of PSW(Program Status Word)
Ans: (d)
6. Frequency at which VOICE is sampled is…
a) 4 KHz
b) 8 KHz
c) 16 KHz
d) 64 KHz
Ans: (a)
7. Line of sight is…
a) Straight Line
b) Parabolic
c) Tx & Rx should be visible to each other
d) none of the above
Ans: ©
8. Purpose of PC(Program Counter) in a MicroProcessor is…
a) To store address of TOS(Top Of Stack)
b) To store address of next instruction to be executed.
c) count the number of instructions.
d) to store base address of the stack.
Ans: (b)
9. What action is taken when the processor under execution is interrupted by a non-maskable interrupt?
a) Processor serves the interrupt request after completing the execution of the current instruction.
b) Processor serves the interrupt request after completing the current task.
c) Processor serves the interrupt request immediately.
d) Processor serving the interrupt request depends upon the priority of the current task under execution.
Ans: (a)
10. The status of the Kernel is…
a) task
b) process
c) not defined.
d) none of the above.
Ans: (b)
11. What is the nominal voltage required in subscriber loop connected to local exchange?
a) +48 volts
b) -48 volts
c) 230 volts
d) 110 volts
12. To send a data packet using datagram , connection will be established…
a) before data transmission.
b) connection is not established before data transmission.
c) no connection is required.
d) none of the above.
Ans: ©
13. Word alignment is…
a) aligning the address to the next word boundary of the machine.
b) aligning to an even boundary.
c) aligning to a word boundary.
d) none of the above.
Ans: (a)
14. When a C function call is made, the order in which parameters passed to the function are pushed into the stack is…
a) left to right
b) right to left
c) bigger variables are moved first than the smaller variales.
d) smaller variables are moved first than the bigger ones.
e) none of the above.
Ans: (b)
15. What is the type of signaling used between two exchanges?
a) inband
b) common channel signaling
c) any of the above
d) none of the above.
Ans: (a)
16. Buffering is…
a) the process of temporarily storing the data to allow for small variation in device speeds
b) a method to reduce cross talks
c) storage of data within transmitting medium until the receiver is ready to receive.
d) a method to reduce routing overhead.
Ans: (a)
17. Memory allocation of variables declared in a program is…
a) allocated in RAM.
b) allocated in ROM.
c) allocated on stack.
d) assigned to registers.
Ans: ©
18. A software that allows a personal computer to pretend as a computer terminal is …
a) terminal adapter
b) bulletin board
c) modem
d) terminal emulation
Ans: (d)
A+ and basic PC questions
A+ and basic PC questions
What are the basic expansion card types?ISA and PCI, ISA can be used only on XT, AT and ATX boards. The industry now considers ISA obsolete.
How do you clear CMOS password? Since CMOS is a special chip with its own battery, the best way to clear out a CMOS chip is to disconnect it from its power supply.
Where does the Real mode on the CPU come from? The original 8086, which only had 1 MB of memory. This megabyte is split into low memory for IRQ tables, application memory and high memory.
Where does CPU Enhanced mode originate from? Intel’s 80386 was the first 32-bit processor, and since the company had to backward-support the 8086. All the modern Intel-based processors run in the Enhanced mode, capable of switching between Real mode (just like the real 8086) and Protected mode, which is the current mode of operation. (more…)
Intel interview questions
Intel interview questions
The following questions are used for screening the candidates during the first interview. The questions apply mostly to fresh college grads pursuing an engineering career at Intel.
Have you studied buses? What types?
Have you studied pipelining? List the 5 stages of a 5 stage pipeline. Assuming 1 clock per stage, what is the latency of an instruction in a 5 stage machine? What is the throughput of this machine ?
How many bit combinations are there in a byte?
For a single computer processor computer system, what is the purpose of a processor cache and describe its operation?
Explain the operation considering a two processor computer system with a cache for each processor.
What are the main issues associated with multiprocessor caches and how might you solve them?
Explain the difference between write through and write back cache.
Are you familiar with the term MESI? (more…)
x86 interview questions
x86 interview questions
These interview questions test the knowledge of x86 Intel architecture and 8086 microprocessor specifically.
What is a Microprocessor? - Microprocessor is a program-controlled device, which fetches the instructions from memory, decodes and executes the instructions. Most Micro Processor are single- chip devices.
Give examples for 8 / 16 / 32 bit Microprocessor? - 8-bit Processor - 8085 / Z80 / 6800; 16-bit Processor - 8086 / 68000 / Z8000; 32-bit Processor - 80386 / 80486.
Why 8085 processor is called an 8 bit processor? - Because 8085 processor has 8 bit ALU (Arithmetic Logic Review). Similarly 8086 processor has 16 bit ALU.
What is 1st / 2nd / 3rd / 4th generation processor? - The processor made of PMOS / NMOS / HMOS / HCMOS technology is called 1st / 2nd / 3rd / 4th generation processor, and it is made up of 4 / 8 / 16 / 32 bits.
Define HCMOS? - High-density n- type Complimentary Metal Oxide Silicon field effect transistor. (more…)
8085 microprocessor questions
8085 microprocessor questions
What are the various registers in 8085? - Accumulator register, Temporary register, Instruction register, Stack Pointer, Program Counter are the various registers in 8085 .
In 8085 name the 16 bit registers? - Stack pointer and Program counter all have 16 bits.
What are the various flags used in 8085? - Sign flag, Zero flag, Auxillary flag, Parity flag, Carry flag.
(more…)