Electronics

Question 1

thevenin’s theorem

Answer 1

Any linear circuit containing several voltages and resistances can be replaced by just one single voltage in series with a single resistance connected across the load

Question 2

thevenin’s algorithm

Answer 2

Find the Thevenin source voltage by removing the load resistor from the original circuit and calculating the voltage across the open connection points where the load resistor used to be.

Find the Thevenin resistance by removing all power sources in the original circuit (voltage sources shorted and current sources open) and calculating total resistance between the open connection points.

Draw the Thevenin equivalent circuit, with the Thevenin voltage source in series with the Thevenin resistance. The load resistor re-attaches between the two open points of the equivalent circuit.

Analyze voltage and current for the load resistor following the rules for series circuits

Question 3

Converting to phasor

Answer 3

given a sine function: -90 degrees to convert into cosine
CONVERT to RMS: take max/sqrt(2) = Vrms
I = V/R

Question 4

laplace transform

Answer 4

pg 55, math section

Question 5

(a/b)/(c/d)

Answer 5

ad/dc

Question 6

laplace transform with time delay:

te^(-at)*u(t-1)

Answer 6

-we can write the equivalent equation with time delay
(t-1+1)e^-a[t-1+1]*u(t-1)

-lets factor out the e^-a term:
[(t-1)e^-a(t-1)u(t-1) + e^-a(t-1)u(t-1)]e^-a

-the time advance (t-1) means that the value is put in the front, and we can change the 2 terms to respective LT pairs
e^-(s+a) [1/(s+a)^2 + 1/(s+a) ]

Question 7

shifting properties of delta function:
S f(t)delta(t-T)dt = f(T)

Answer 7

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Question 8

Diode Analysis

Answer 8

Assume all on, check currents; if i1 >0 works and i2 >0 works then done

check D1 On and D2 off:
for Diode on: i >0
for voltage off concerning only voltages (forget about resistors in series for KVL): if v <0 then DONE

Question 9

MOSFETS:
N Channel:

in Saturation?
Vgs > Vt
Vgd < Vt
In Triode:
Vgs > Vt
Vgd >Vt

P- Channel:

Vsg - Vsd = Vdg

Answer 9

l

Question 10

Power Electronics

Answer 10

Chopper (DC to DC)
Inverter (DC to AC)
Rectifier (AC to DC)
Cyclo-converter (AC to AC)

Question 11

Percent Error Formula

Answer 11

(Iactual - Imeasured)/(Iactual)

Question 12

Max Power Transfer (AC!)

Answer 12

ZL = Z*th
Short Voltage Sources
Open Current Sources

Question 13

Van, Vbn, Vcn

Answer 13

Line voltages (Vab, Vbc, Vca) lead phase voltages (Van..) by 30 degrees and are greater than a factor of sqrt(3)

Question 14

given a delta - wye : network

Answer 14

given Vab, we know that Van lags by 30 and is smaller by a factor of sqrt(3) ; Ian = Van/ Zph

Question 15

given wye - delta network: convert load to wye

Answer 15

Zdelta/3 = Zwye;

Question 16

power losses

Answer 16

Ploss = Psource - Pload

Question 17

Single Phase Power: P =VIcos(theta)

3-Phase Power: P = 3*VIcos(theta)

Question 18

Addressing modes: unique ways in which address of an operand is given in an instruction

Answer 18

register addressing mode- used when operands are in registers
immediate addressing mode - used when operands are stored part of instructions i.e. constants
direct addressing mode- used when operands are provided in memory addressing modes

other examples include indirect addressing mode, memory deferred addressing mode, scaled addressing mode

Question 19

complier

Answer 19

complier- language processor that converts high level language (source code) into machine language

Question 20

interpreter

Answer 20

interpreter- language processor that converts high level language (source code) inter an intermediate (low level lanugage) for execution

Question 21

the difference between an interpretter and complier is that as opposed to an interpreter a complier translates the program into machine language before execution

Answer 21

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Question 22

assembler

Answer 22

assembler- language processor that converts assembly language (source code) into machine language (object code) for execution

Question 23

control unit

Answer 23

control init is part of computer’s CPU (central processing unit) it directs the operation of memory unit, arithmetic logic unit and I/O units by interpreting instructions

Question 24

I/O unit

Answer 24

the I/O unit comprise devices used to enter and extract details to and from a computer

Question 25

ALU

Answer 25

Arithmetic Logic Unit- responsible for making mathematical and logical operations

Question 26

batch data processing

Answer 26

involves processing high volume data in groups / batches. It is an efficient way of processing quarterly banks statements, payroll, school reports, etc.

Question 27

real time data processing

Answer 27

it involves continuous data processing. it is an efficient way of processing stock quotation, customer services. etc.

Question 28

RAM

Answer 28

random access memory - typically volitle and BIOS is loaded into RAM only after computer boots

Question 29

ROM

Answer 29

Read only memory - nonvolatile and BIOS is gnerally store din RIM which is used to boot the computer

Question 30

USB Mass storage Device

Answer 30

typically used as secondary memory storage device for porable data storage options

Question 31

Encryption

Answer 31

Encryption - A data conversion process which prevents unauthorized personnel from accessing it.

Question 32

encoding

Answer 32

Encoding - A data transformation process involving changing data format for another system.

Question 33

hashing

Answer 33

Hashing - Transformation of string into shorter fixed length value representing original string.

Question 34

decoding

Answer 34

Decoding - It is the opposite of encoding and converts encoded data to its original format.

Question 35

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Answer 35

Instruction pipelining increases instruction throughput. It neither decreases the instruction execution time nor
does it allow new types of instructions.

Question 36

microprocessors

Answer 36

Program counter register - contains address of next instruction to be executed.

Stack pointer register - contains address of last executed instruction.

Instruction pointer register - contains address of the current instruction being executed.

Accumulator register - contains results of arithmetic and logic operations.

Question 37

microprocessors cont

Answer 37

Microprocessor-A single Integrated Circuit (1C) accepting & executing code instructions for processing data and controlling associated circuitry in a computer system
Microcomputer - An interconnected group of Integrated Circuits (ICs), l/Os and memory systems used for data processing and other applications.

Microcontroller - An integrated system of a single 1C, l/Os, memory system and associated circuitry accepting & executing coded instructions in computer system.

Question 38

cont

Answer 38

Address Bus - carries physical address for reading/writing.
Data Bus - carries data between different units of a computer system.
Control Bus - connects CPU with other components.