Electronics Flashcards
thevenin’s theorem
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
thevenin’s algorithm
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
Converting to phasor
given a sine function: -90 degrees to convert into cosine
CONVERT to RMS: take max/sqrt(2) = Vrms
I = V/R
laplace transform
pg 55, math section
(a/b)/(c/d)
ad/dc
laplace transform with time delay:
te^(-at)*u(t-1)
-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) ]
shifting properties of delta function: S f(t)delta(t-T)dt = f(T)
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Diode Analysis
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
MOSFETS:
N Channel:
in Saturation? Vgs > Vt Vgd < Vt In Triode: Vgs > Vt Vgd >Vt
P- Channel:
Vsg - Vsd = Vdg
l
Power Electronics
Chopper (DC to DC)
Inverter (DC to AC)
Rectifier (AC to DC)
Cyclo-converter (AC to AC)
Percent Error Formula
(Iactual - Imeasured)/(Iactual)
Max Power Transfer (AC!)
ZL = Z*th
Short Voltage Sources
Open Current Sources
Van, Vbn, Vcn
Line voltages (Vab, Vbc, Vca) lead phase voltages (Van..) by 30 degrees and are greater than a factor of sqrt(3)
given a delta - wye : network
given Vab, we know that Van lags by 30 and is smaller by a factor of sqrt(3) ; Ian = Van/ Zph
given wye - delta network: convert load to wye
Zdelta/3 = Zwye;
power losses
Ploss = Psource - Pload
Single Phase Power: P =VIcos(theta)
3-Phase Power: P = 3*VIcos(theta)
Addressing modes: unique ways in which address of an operand is given in an instruction
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
complier
complier- language processor that converts high level language (source code) into machine language
interpreter
interpreter- language processor that converts high level language (source code) inter an intermediate (low level lanugage) for execution
the difference between an interpretter and complier is that as opposed to an interpreter a complier translates the program into machine language before execution
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assembler
assembler- language processor that converts assembly language (source code) into machine language (object code) for execution
control unit
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
I/O unit
the I/O unit comprise devices used to enter and extract details to and from a computer
ALU
Arithmetic Logic Unit- responsible for making mathematical and logical operations
batch data processing
involves processing high volume data in groups / batches. It is an efficient way of processing quarterly banks statements, payroll, school reports, etc.
real time data processing
it involves continuous data processing. it is an efficient way of processing stock quotation, customer services. etc.
RAM
random access memory - typically volitle and BIOS is loaded into RAM only after computer boots
ROM
Read only memory - nonvolatile and BIOS is gnerally store din RIM which is used to boot the computer
USB Mass storage Device
typically used as secondary memory storage device for porable data storage options
Encryption
Encryption - A data conversion process which prevents unauthorized personnel from accessing it.
encoding
Encoding - A data transformation process involving changing data format for another system.
hashing
Hashing - Transformation of string into shorter fixed length value representing original string.
decoding
Decoding - It is the opposite of encoding and converts encoded data to its original format.
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Instruction pipelining increases instruction throughput. It neither decreases the instruction execution time nor
does it allow new types of instructions.
microprocessors
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.
microprocessors cont
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.
cont
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.
