Microprocessor

Question 1

The range of voltages between VL(max) and
VH(min) are _____.
a. unknown
b. unnecessary
c. unacceptable
d. between 2 V and 5 V

Answer 1

C. Unacceptable

Question 2

In a certain digital waveform, the period is four times the pulse width. The duty cycle
is ________.
a. 0%
b. 25%
c. 50%
d. 100%

Answer 2

B. 25%
T = 4PW
DC = PW/T x 100 %
= PW/4PW x 100%
= 1/4 x 100%
= 25%

Question 3

Which statement is correct?
a. power dissipation in CMOS is essentially constant. It’s extremely high under static
condition
b. power dissipation in CMOS is frequency dependent. It’s extremely low under static
condition
c. power dissipation in TTL circuit is frequency dependent over its range of operating
frequencies
d. power dissipation in TTL circuit is frequency dependent and it’s extremely low
under static condition

Answer 3

B

Question 4

For a CMOS gate, which is the best speed-power product?
a. 1.4 pJ
b. 1.6 pJ
c. 2.4 pJ
d. 3.3 pJ

Answer 4

A. 1.4 pJ, the lower the better

Question 5

The active switching element used in all TTL circuits is the ______.
a. bipolar junction transistor (BJT)
b. field-effect transistor (FET)
c. metal-oxide semiconductor field-effect transistor (MOSFET)
d. unijunction transistor (UJ)

Answer 5

A. Bipolar Junction Transistor (BJT)

Question 6

The bipolar TTL logic family that was developed to increase switching speed by
preventing transistor saturation is:
a. emitter-coupled logic (ECL)
b. current-mode logic (CML)
c. transistor-transistor logic (TTL)
d. emitter-coupled logic (ECL) and transistor- transistor logic (TTL)

Answer 6

A. Emitter-coupled logic (ECL)

Question 7

PMOS and NMOS circuits are used largely in ________.
a. MSI functions
b. LSI functions
c. diode functions
d. TTL functions

Answer 7

B. LSI Functions (large scale integration)

Question 8

In a TTL circuit, if an excessive number of load gate inputs are connected, ________.
a. VOH(min) drops below VOH
b. VOH drops below VOH(min)
c. VOH exceeds VOH(min)
d. VOH and VOH(min) are unaffected

Answer 8

B. VOH drops below VOH(min)

Question 9

An open collector output can ____ current, but it cannot ____.
a. sink, source current
b. source, sink current
c. sink, source voltage
d. source, sink voltage

Answer 9

A. Sink, Source Current

Question 10

A classification of IC’s with complexities of 12 to 100 equivalent gates on a chip is
known as ________.
a. SSI
b. MSI
c. LSI
d. VLSI

Answer 10

B. MSI

Question 11

Which is not an output state for tristate logic?
a. active HIGH
b. active LOW
c. Low-Impedance
d. High-Impedance

Answer 11

C. Low Impedance

Question 12

The application of feedback in digital electronics is:
a. store data
b. for radio station
c. not use
d. for combinational logic circuit

Answer 12

A. Store Data

Question 13

A basic computer does not include:
a. an arithmetic logic unit
b. a control unit
c. peripheral units
d. a memory unit

Answer 13

C. Peripheral Units

Question 14

A basic computer does not include:
a. an arithmetic logic unit
b. a control unit
c. peripheral units
d. a memory unit

Answer 14

C. Peripheral Unit

Question 15

DYNAMIC memory cells store a data bit in a ______.
a. diode
b. resistor
c. capacitor
d. flip-flop

Answer 15

C. Capacitor

Question 15

Select the statement that best describes Read-Only Memory (ROM).
a. nonvolatile, used to store information that changes during system operation
b. nonvolatile, used to store information that does not change during system
operation
c. volatile, used to store information that changes during system operation
d. volatile, used to store information that does not change during system operation

Answer 15

B. nonvolatile, used to store information that does not change during system

Question 16

A major disadvantage of the mask ROM is that it:
a. is time consuming to change the stored data when system requirements change
b. is very expensive to change the stored data when system requirements change
c. cannot be reprogrammed if stored data needs to be changed
d. has an extremely short life expectancy and requires frequent replacement

Answer 16

C. cannot be reprogrammed if stored data needs to be changed

Question 17

In general, the ______ have the smallest bit size and the ____ have the largest.
a. EEPROMs, Flash
b. SRAM, mask ROM
c. mask ROM, SRAM
d. DRAM, PROM

Answer 17

A. EEPROMS, Flash

Question 18

In a DRAM, what is the state of R/W during a read operation?
a. Low
b. High
c. Hi-Z
d. None of the above

Answer 18

B. High

Question 19

Which of the following computer memories is fastest?
a. Cache
b. Primary
c. Mass storage
d. Off line back up

Answer 19

A. Cache

Question 20

Most devices are interfaced to a bus with _______. It’s also a type of circuit used at the interface point of an input port.
a. totem-pole outputs
b. tri-state buffers
c. pnp transistor
d. resistors

Answer 20

B. Tri-state Buffers

Question 21

The process of jointly establishing communication is called:
a. DMA
b. bidirectional addressing
c. multiplexing
d. handshaking

Answer 21

D. Handshaking

Question 22

An I/O processor control the flow of information between:
a. cache memory and I/O devices
b. main memory and I/O devices
c. 1 Two I/O devices
d. cache and main memories

Answer 22

B. Main Memory and I/O Devices

Question 23

Polling is the method used for:
a. determining the state of a microprocessor
b. establishing communication between CPU and a peripheral
c. establishing a priority for communication with several peripherals
d. determining the next instruction

Answer 23

B. establishing communication between CPU and a peripheral

Question 24

The technique of assigning a memory address to each I/O device in the computer system is called: a. memory-mapped I/O b. ported I/O c. dedicated I/O d. wired I/O

Answer 24

A. Memory-mapped I/O