Lecture 8 (Excluded) Flashcards
Very high gain amplifiers with very wide bandwidth, very
high input impedance (typically a few megaohms) and low output impedance (less than 100
ohms).
Operational Amplifiers
Ideal op-amp
has infinite voltage gain, infinite input impedance, and zero output
impedance
the ________ of an op amp is a differential amplifier, and it contains a number of amplifier stages to achieve a very high voltage gain.
input
Two inputs of op amps
Non-inverting input (with + sign) and inverting input (with – sign)
Op amps could have ______ outputs.
one or two
Op amps typically use a _____ power supply.
positive and negative
It provides amplification between the difference of the two input voltages
Differential Amplifier (Input Stage)
It provides additional gain
Voltage Amplifier (Gain Stage)
It provides better power output
Push-Pull Amplifier (Output Stage)
The term _______ refers to its capabilities to perform mathematical operations (Add, subtract, differentiate and integrate) as its main applications
operational
An input of op amps wherein one input is connected to the ground.
single-ended input
both input pins have
input signal.
double-ended input
It is the ability of an op amp to reject the common signals at its inputs.
Common mode rejection
The differential connection of op amps typically _____ noise significantly.
reduce
Desired signals can appear on only in __________ while unwanted signal appear in ____________
differential mode, common
mode
An op-amp provides a very high gain for differential-mode signals and _______ for common-mode signals.
zero gain
It exhibit a very small gain (less than 1), while providing a high open-loop differential voltage gain (several thousands).
practical op-amps
The good measure of an op-amp’s performance in rejecting unwanted common-mode signals is thru _______.
CMRR
It is an op amp specification which indicates the voltage gain of an op amp when there is no feedback resistor.
Open loop voltage gain
The gain of the op amp circuit when there is a feedback resistor.
Closed loop gain
It is defined as how much current change occurs in the input offset voltage for each degree change in temperature.
Offset voltage drift
The typical value of the voltage drift is in the range of ______ per
degree Celsius.
5μV to 50μV
Op-amps with a higher nominal value of input offset voltage exhibits a ________ drift.
higher
The dc current required by the input of the amplifier to properly operate the first stage of an op-amp
Input bias current.
Total resistance between inverting and non inverting input as. It can be measured by determining the change in bias current for a given change in differential input voltage.
Differential Input Impedance
The total resistance between each input terminal and ground It can be measured by determining the change in bias current for a given change in common-mode input voltage.
Common-Mode Input Impedance
It is the absolute value of the difference of the input bias currents
Input offset current
It is measured across the output terminal of the op-amp.
Output impedance
It is defined as the maximum rate of change of the output voltage in a step input voltage. It is dependent upon the high-frequency response of the amplifier stages within the op-amp
Slew rate
Since op-amp doesn’t have coupling capacitors, its low frequency response extends down to _____
(dc).
0Hz
It is the process of returning the output voltage of amplifier to the input with a phase angle that opposes the input signal.
Negative feedback
It also provide stable voltage gain, and control of the input and output impedances and amplifier bandwidth.
Negative feedback
It is the voltage gain with external feedback circuit.
Closed-loop voltage gain
It indicates how the voltage gain changes with frequency
Frequency response
It indicates how the phase shift between the input and output signal changes with frequency.
Phase response
