Lectures Flashcards
How to calculate Rc in an Inverting Amplifier
Rc = R1 || Rf
How is Rc calculated in a Non-Inverting Amplifier?
Rc = R2 || R1
How to calculate Rc in a buffer ?
Rc = Rs
What is a virtual short
When the voltage of the inverting input of an ideal op-amp will tracks the non-inverting input
V- = V+ - Vdif
What does KCL mean
The sum of the current entering a node equals the sum of the current leaving the node
What does KVL mean
The sum of the voltages around a loop is zero
What is the op Amp Rule
An ideal op-amp with negative feedback so output whatever voltage and current are needed to drive Vdiff to zero
What is the frequency response of an op-amp
Frequency has an internal compensation capacitor to maintain stability, so it won’t oscillate resulting in a low frequency pole in the transfer function
What is gain bandwidth product (GBP)
The parameter that defines the frequency range over which an operational amplifier can maintain a specific gain. It Is the product of the amplifiers gain (Av) and bandwidth (f)
What is the impedance of a non-inverting circuit
Infinite
What is the gain of a non inverting circuit ?
1 + (R2/R1)
What is the input impedance of an inverting circuit
R1
What is the gain of an inverting circuit
-(R2/R1)
What’s voltage gain in dB
20log(Gain)
What is feedback used to control
Open loop gain and bandwidth
What is the output in an integrating op-amp
Voltage which is proportional to the input voltage with respect to time
How is the magnitude determined of an inverting op-amp
By the length of time a voltage is present
How can a integrator be made
By putting a capacitor in the feedback position (R2 in an inverting circuit)
What is impedance
Frequency - dependent resistance (with a phase shift)
What is the voltage calculation for a capacitor
1/(jwC) X I
What is the voltage calculation of an inductor
jwL X I
What is the phase shift in a resistor
0 deg
What is the phase shift of an inductor
90 deg
What is the phase shift of a capacitor
-90 deg
I(wt) = ?
I0 Cos (wt) + jI0 Sin (wt)
Frequency dependant gain H(w) = ?
1/(1 + jwCR)
What is the frequency and capacitance in a open circuit high pass filter
F = 0 Hz, C = infinity (ohm)
What is the frequency and capacitance of a short circuit hight pass filter
F = infinite Hz, C = 0 ohm
What is half time
The time taken by charge on capacitor to double or half
