midterm Flashcards
(134 cards)
1
Q
Where can you find Alternating Current (AC)?
A
all wall ports in home and switches
2
Q
where can you find direct current (DC)?
A
all batteries, computer, chargeable and car
power supply: computer and normal
3
Q
what devices work with AC
A
Light bulbs, fridge, washing machine, kettle
4
Q
what devices work with dc
A
all electronic devices: cameras, laptops, smartphones
5
Q
converting ac to dc requires…
A
all electronic devices have converter (some electronic components) that converts AC to DC
6
Q
_____ convert AC to DC and DC to AC
A
ELECTRONC DEVICES
7
Q
AC ______ direction___
A
changes
from time to time positive to negative and negative to positive
8
Q
DC ____ direction ___
A
stays in same
all the time
9
Q
in our lectures we use __
A
DC
10
Q
DC source is measured in ____ and acts as a ______
A
voltage
storing room or tank
11
Q
DC source in series (ex,two 1.5 V batteries, results in ___)
A
3 volts (add voltage)
12
Q
DC source in parallel (ex, three 1.5 V batteries, results in ___)
A
1.5V (no addition
13
Q
Explain Tank Example
A
tank filled with water, 3 main elements
source: tanks its self (ie tank/ storage room)= power supply (volt)
tap: controls the flow of water through the pipe (flow control) = resistance (ohm)
flow of liquid: amount of flow = current (amp)
higher you close the water tap, the less flow of water
aka
higher resistance value, less current
14
Q
write relating eq of I,V,R and A,V,Ohm
A
I=V/R —-> A = volt/ ohm
15
Q
current is __
A
stream of electrons, flows from positive terminal to negative terminal
16
Q
what is a resister
A
allows user to control the
flow of current
voltage drop
no way to design electronic or digital circuit without using resistors
17
Q
refresh how to read reisistors
A
slide 24
18
Q
reversing polarity of battery implies__
A
reversing current direction
19
Q
variable resistor
A
can have its electrical resistance adjusted
20
Q
GND and VCC, and V+
A
gnd = ground (-)
v+ = positive terminal of dc source (+)
vcc = voltage at common collector (+)
21
Q
capacitors
A
store electric energy (voltage)
can act as temporary battery
used to maintain constant power supply and remove ripples in voltage
22
Q
series resistors: same ___ through every resistor but ___ divider
A
current
voltage
23
Q
parallel resistors: same ___ through every resistor but ___ divider
A
voltage
current
24
Q
what is an LED
A
light emitting diode
semiconductor component that emits light whenever current flows through it
25
LED recommended flow of current
LESS THAN 7-20 mA
26
diodes
allow electric current to pass through one specified direction (pos to neg) called forward bias
blocks current in opposite direction *neg to pos) called reverse bias
26
diode
when current tries to travel from neg to pos, diode acts as ____
open switch
27
every diode has ___ limit
diode and LED (light up) if _____ >____
called ___
voltage
applied voltage
voltage limit
Breakdown mode
28
diode has voltage drop if ____V
0.7
29
different types of diodes - slide 14/15
30
switches and push buttons used for
controlling status of circuit -> open or closed
also used to
start
stop
emergency
activation
open /close part of circuit
31
bush buttons and switches can be defines as ____
mechanical switches
32
transistors and MOSFETs can be defined as
electrical switches (powerful swicthes)
33
2 types of transistors and components + draw circuit (slide 5)
NPN -Current away
PNP - current towards
c= collector
b=base
e=emitter
34
type of MOSFET + components
N-channel
g=gate
d=drain
s=source
35
transistors vs mosfet
transistor terminals:
transistors are all about ___
transistors base is ______ to emitter
transistor used for ___ applications
mosfet terminals:
mosfet are all about ___
mosfet gate is ____
mosfet used for ___ applications
c= collector
b-base
e=emitter
current
connected
low current
g=gate
d-drain
s=source
voltage
insulated
powerful and high current
36
sequential circuit composed of
interconnecting combination circuit + storage elements
37
storage elements are
similar to computer memory that stores bits (ones and zeroes)
38
states are
normally combinations of bits
39
next state is dependent on ____ and _____
current state and current input
next state= f(inputs, state)
40
if out puts depends on current input and current state, model is called
outputs=f(inputs, state)
41
if out puts depends on current state, model is called
moore model
outputs=f(state)
42
types of sequential circuits
synchronous
asynchronous
43
types of sequential circuits: synchronous
behaviour defined through knowledge of its signal at discrete instance of time
storage elements observe inout data and update state in response to timing signal (clock pulses)
easy to design and use
more popular/used
44
types of sequential circuits: asynchronous
behaviour defined through knowledge of input signal at any instance of time (continuous time)
very hard to design (different gates give you different propagation time)
45
storage elements can be constructed using _____ in a_____ looop
2 inverters
close
46
it is not possible to ____ stored info - why?
change
problem: when you turn on circuit you cannot guarantee what value of Q - value depends on stored capacitance of previous usage
47
capacitors
store voltage
take out discrepancies
48
inductors
help avoid fluctuation in current
49
types of capacitors
ceramic
electronic
carbon film
tantalum
50
transformers
Ns>Np
step up transformer
51
transformers
Ns
step down transformer
52
transformers only act ____ to ___
AC to AC
53
Transformer voltage typically between
5-10 V
54
junction diode
small electric field develops across thin layer of depletion region due to diffusion of electron if it passed the required voltage difference (0.6-0.7V)
55
zener diode
known as__
key is ___
change in __ is related to change in __
has ____ resistance
known as voltage regulator diode
key is breakdown voltage
current
voltage
dynamic
56
transistor
___ current at ____ allows ___ current to flow between ____and ____
small
base
more
collector
emitter
57
transistor
___ current at base ____ current amount at collector to E
increase increase
58
transistor is current ___
amplifier
59
FET
Field effect transistor
enhancement mode metal oxide semi conductor
depletion mode MOSFET
junction field transistor (JFET)
60
MOSFET - N channel
amount of voltage at ___ will modulate ______
does not ___at circuit
gate
channel resistance
draw any current
61
MOSFET - N channel
current flow between __ and ___ based on the amount of ___ applied at ____
drain
source
voltage
gate
62
MOSFET
purpose
types
components
__ control device
input resistance is ___
dissipates ___ heat
switch speed is ____
__ sensitive to temp
amplify and switch
n channel and p cahnnel
g,s,d
voltage
high
more
high
less
63
BJT
purpose
types
components
__ control device
input resistance is ___
dissipates ___ heat
switch speed is ____
sensitive to ___ temp
amplifies and switch
npn and pnp
b,c,e
very low
less
low
high
64
relay
electromechanical switch
needs to be replaced frequently
all coil = DC
take 9-12V
65
amplifier
senors(transducers) - analog signal
small (mV or mA)
noisy (filter cut noise)
to handle offset
66
purpose of amplifiers
amplify signal
handle noise
control system
filter design
67
ideal amp can supply
infinity gain
68
ideal amp
there is a _____ voltage (pointing ___and __) and ____ ( __ value)
supply
up and down
source
maximum
69
numbering systems
# digits and list of digits
decimal-0123456789
binary-01
hexidecimal-0123456789ABCDEF
octal- 01234567
70
buffer
a=1 y=
a=0 y=
1
0
71
not gate
a=0 y=
a=1 y=
1
0
72
and gate
a=0 b=0 y=
a=1 b=0 y=
a=0 b=1 y=
a=1 b=1 y=
0
0
0
1
73
or gate
a=0 b=0 y=
a=1 b=0 y=
a=0 b=1 y=
a=1 b=1 y=
0
1
1
1
74
universal gate
NAND Gate
nor gate
75
Nand gates
a=0 b=0 y=
a=1 b=0 y=
a=0 b=1 y=
a=1 b=1 y=
1
1
1
0
76
nor gate
a=0 b=0 y=
a=1 b=0 y=
a=0 b=1 y=
a=1 b=1 y=
1
0
0
0
77
xor gate
a=0 b=0 y=
a=1 b=0 y=
a=0 b=1 y=
a=1 b=1 y=
0
1
1
0
78
xnor gate
a=0 b=0 y=
a=1 b=0 y=
a=0 b=1 y=
a=1 b=1 y=
1
0
0
1
79
decoders
made of logic circuits
converts n-bit to m-bits
80
decoders
n less than or equal to m
every valid input will result in a unique output
81
encoder
reverse process of decoder
convert mbit input to nbit output
81
multiplexers
helps to select info from one of inputs (2^n) using selectors (n) and pass it to (1) ouput
82
to design multiplexer 4-to-1 need
1 decoder
2 input AND gates
multi-input OR gates
83
demultiplexer
select info from input (one input) and directs to one of 2^n outputs using selectors
84
ss
rs
us
set state
reset state
undefined state
85
negative edge triggered d flip flop
d flip flop is composed of __ latches which are
q changes only at ____ of synchronizing or control clok (clk)
2
first is called master and second is called slave
negative edge
86
negative edge triggered d flip flop
triangle next to clk refers to ____
bubble or small circle with triangle refers to _____
edge triggered
negative edge triggered
87
positive edge triggered d flip flop
q changes only at ____ of synchronizing or control clok (clk)
positive
88
JK FLIP-FLOP
designed using _____
d flip flop and logic gates
89
T flip flop design using ___
d flip flop and logic gates
90
applications of flip flops
shift registers: parallel,serial,data storage: serial and parallel
counters:count # of pulses
91
what are registers
made of set of flip flops
used to store and manipulate info
92
n bit register made of ___
n set of flip flops
93
simple register has
flipflops connected to a common clock signal, no extra logic components are involved in he design
94
registers: d flip flop with active low
4 bit register with active low clear signal
___ flip flops next to each other
each has ____
all have ____
4
data line I0,I1,I2...
common clock and active low rest/ clear signal
95
registers: d flip flop with active low
limitation
need to store value into register and leave it until we use it or store new value
used in computers and computer clock signal is very fast
solve by introducing load signal using an enabling circuit
96
registers: d flip flop with active low
introducing load signal
prevent clock from reaching register when load input is low as c input will be '1'
97
registers: d flip flop with active low
clock signal will reach ___ if and only if ____
called ____
c input
load input is high '1'
clock gating
98
registers: d flip flop with active low
problem: adding additional logic in clock path will introduce delay
problem: clock elements may be received at different times due to logic circuit in clock path
known as___
result of ___
clock skew
malfunction if flip flops inputs and outputs are dependent
99
registers: d flip flop with enable
possible solution
deign a d flip flop with enable this way we ___
if EN =0 D=___
if EN=1 then D=___
avoid extra logic design in clock path
Q
I
100
SHIFT REGISTER
register is capable of shifting binary info stored in every cell to its neighbouring cell according to preselected direction
101
shift register
all flip flops receive _____. the ____ activate shift of data from one cell to the next
clokc pulses
clock pulses
102
shift registers: serial transfer
datapath of digital system can be ____ or ___ . __ is more common
datapath of digital system said to operate in ____ of info is transferred and manipulated ____
data transferred one bit at a time via shifting bits out of ____ into ____
parallel transfer means___
serial
parallel
serial
serial mode
one bit at a time
source register
destination register
all bits of register transferred at same time
103
computer arch
simple single processor computer
components
cpu
main memory
i/0
system interconnection (system bus)
104
cpu (central processing unit) referred to as a processor and controls
controls computer operation
performs data processing
105
main memory
stores data
106
i/o
moves data to/from computer from/to its external environment
107
system interconnection (system bus)
mechanism that provides communication among CPU, main memory and I/0
108
CPU consists of
control unit
arithmetic and logic unit (alu)
registers
cpu interconnection (data path)
109
control unit
control operation of CPU which means that it control computer
110
arithmetic and logic unit (alu)
performs computer data processing functions
111
cpu interconnection (data path)
mechanism that provides communication through control unit , (ALU) and registers
112
registers
provides internal storage as well as manipulation to CPU
113
WHAT ARE COUNTERS
digital device that used to count number of pulses
used as frequency divider
used to count
up (1,2,3,N)
down (N,N-1,N-2)
inegration of flipflops
114
n bit counter is made of __ set of flipflops also n-nit counter can count up to ___counts / states
n
2^n
115
counters may be classified as _____and ___
asynchronous
synchronous
116
asynchronous counter
made of flipflopswith different Clk pulses for each flip flop
ex: ripple counter (up and doe)
117
synchronous counter
made of flipflops with dame clk pulses
ex up and down counters
118
3 bit ripple counter gives ___possible counts
2^3=8
119
4 bit ripple counter gives ___possible counts
2^4=16
120
2 bit up counter gives ___possible counts
2^2=4
121
3 bit up counter gives ___possible counts
2^3=8
122
power formula
P=VI
P=I^2*R
123
Transformer formula
Vp/Np =Vs/Ns
124
draw buffer and eq
see notes
125
draw not gate and eq
126
draw and gate and eq
127
draw or gate and eq
128
draw nand gate and eq
129
draw nor gate and eq
130
draw xor gate and eq
131
draw xnor gate and eq
132
