Quiz 2. Analog Signals Flashcards
______ stop the flow of current.
resistors
______ need changing voltage to produce current
capacitors
_______ need a changing current to produce a voltage
inductors
Ohms Law?
I=V/R
Kirchoff’s voltage law
sum of voltage sources and losses should equal zero in a circuit loop
Krchoff’s current law
sum of current sources and losses should equal zero at a circuit junction (first law)
Power.
give equation. and what number law is this?
P=VI=RI^2
DC-resistor/capacitor:
rules to memorize
fully discharged capacitor is equivalent to short circuit
fully charged capacitor is equivalent to an open circuit
Figure out:
In a RC circuit given, assume the capacitor is initially fully discharged.
What is the current and i and output voltage when:
- the switch is first closed
- at steady state (long time)
- in between these two stages
(FIGURE THIS OUT)
If a signal level is to low what can u use?
amplification
_________ of the signal-Voltage or current or current to voltage
conversion
_________ of a signal- conditioning non linear sensor output to be linear
linearization
______ out noise based on frequency- small AC voltages superimposed onto signals which are typically AC or DC voltages
fitler
___________-drain only a minimal amount of current from a measurement circuit with the measuring device
impedance matching
what is analog filtering
it is a process which changes the relative amplitude of, or eliminates altogether, frequency components of a signal
General information:
filtering can be though of as kind of frequency dependent attenuation, where the signal output of the filter will be attenuated (reduced) at a specified frequency range
General
cut off frequency
- is used to describe the frequency where the filter begins to operate significantly on an incoming signal
- actual point is where output is attenuate by 3dB when compared to the input
what are the basic types of frequency?
low-pass –> keep signals lower than fcl
high pass–> keep signals bigger than fch
band pass –> keep signals between fch and fcl
the cutoff frequency describes
the frequency threshold after which higher frequencies are blocked
if we add two similar filters we get a quicker frequency cut off. this is called a ___ order system.
although this may give better frequency cut off, the components need to be selected carefully to avoid overshoot in the time domain– recall the pendulum and spring
2nd order
__________ is a high-gain dc
differential amplifier. It is basically an integrated circuit
chip with transistors. It has two inputs, negative terminal
v1 (some times called inverting input) and positive
terminal v2 (sometime called non-inverting input) and
one output v0. The effective input to the amplifier is the
voltage difference of the two inputs v1-v2.
Operational amplifier (OPAmp)
current flow into the input of the op amp is zero
– almost true in FET op amps where input currents can
be < pA, but this is not always true in bipolar highspeed
op amps where tens of μA input currents are
found.
Op amp gain is assumed to be infinite
Drives the output voltage to any value to satisfy the
input conditions.
– In reality, saturation occurs when the output voltage
comes close to a power supply rail, but reality does
not negate the assumption, it only bounds it.
voltage follower is often used _____________________
for the construction of buffers for logic circuits
input impedance of the op amp is very high, giving __________________________________
Input impedance of the op amp is very high,
giving effective isolation of the output from the
signal source. You draw very little power from
the signal source, avoiding “loading” effects. This
circuit is a useful first stage
