## Feedback Factor of Low Noise Amplifier Solution

STEP 0: Pre-Calculation Summary
Formula Used
Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain)
α = (gm*Rs-1)/(2*gm*Rs*Av)
This formula uses 4 Variables
Variables Used
Feedback Factor - Feedback Factor is a critical parameter that determines the stability and noise performance of amplifiers.
Transconductance - (Measured in Siemens) - Transconductance is a measure of how much current the amplifier can produce for a given input voltage.
Source Impedance - (Measured in Ohm) - Source Impedance is the opposition to current flow that the source presents to the load.
Voltage Gain - Voltage Gain s a crucial parameter for low-noise amplifiers as it determines the amplifier's ability to amplify weak signals while minimizing noise.
STEP 1: Convert Input(s) to Base Unit
Transconductance: 2.18 Siemens --> 2.18 Siemens No Conversion Required
Source Impedance: 23 Ohm --> 23 Ohm No Conversion Required
Voltage Gain: 8 --> No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
α = (gm*Rs-1)/(2*gm*Rs*Av) --> (2.18*23-1)/(2*2.18*23*8)
Evaluating ... ...
α = 0.0612534902273634
STEP 3: Convert Result to Output's Unit
0.0612534902273634 --> No Conversion Required
0.0612534902273634 0.061253 <-- Feedback Factor
(Calculation completed in 00.020 seconds)
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## < 14 Low-Noise Amplifiers and Mixers Calculators

Feedback Factor of Low Noise Amplifier
Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain)
Return Loss of Low-Noise Amplifier
Return Loss = modulus((Input Impedance-Source Impedance)/(Input Impedance+Source Impedance))^2
Noise Figure of Low Noise Amplifier
Noise Figure = 1+((4*Source Impedance)/Feedback Resistance)+Noise Factor of Transistor
Gate to Source Voltage of Low Noise Amplifier
Gate to Source Voltage = ((2*Drain Current)/(Transconductance))+Threshold Voltage
Threshold Voltage of Low Noise Amplifier
Threshold Voltage = Gate to Source Voltage-(2*Drain Current)/(Transconductance)
Transconductance of Low Noise Amplifier
Transconductance = (2*Drain Current)/(Gate to Source Voltage-Threshold Voltage)
Drain Current of Low Noise Amplifier
Drain Current = (Transconductance*(Gate to Source Voltage-Threshold Voltage))/2
Voltage Gain of Low Noise Amplifier given DC Voltage Drop
Voltage Gain = 2*DC Voltage Drop/(Gate to Source Voltage-Threshold Voltage)
Load Impedance of Low Noise Amplifier
Load Impedance = (Input Impedance-(1/Transconductance))/Feedback Factor
Input Impedance of Low Noise Amplifier
Input Impedance = (1/Transconductance)+Feedback Factor*Load Impedance
Output Impedance of Low Noise Amplifier
Output Impedance = (1/2)*(Feedback Resistance+Source Impedance)
Source Impedance of Low Noise Amplifier
Source Impedance = 2*Output Impedance-Feedback Resistance
Drain Resistance of Low Noise Amplifier
Drain Resistance = Voltage Gain/Transconductance
Voltage Gain of Low Noise Amplifier
Voltage Gain = Transconductance*Drain Resistance

## Feedback Factor of Low Noise Amplifier Formula

Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain)
α = (gm*Rs-1)/(2*gm*Rs*Av)

## What are the drawbacks of using feedback in LNAs?

There are also some drawbacks to using feedback in LNAs, including:

Reduced bandwidth: Feedback can reduce the bandwidth of an LNA. This is because feedback can cause reflections of signals, which can distort the signal and reduce the amplifier's bandwidth.
Increased instability: Feedback can make an LNA more susceptible to oscillation. This is because feedback can create a positive feedback loop, which can cause the amplifier to oscillate.

## How to Calculate Feedback Factor of Low Noise Amplifier?

Feedback Factor of Low Noise Amplifier calculator uses Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain) to calculate the Feedback Factor, The Feedback Factor of Low Noise Amplifier formula is defined as a critical parameter that determines the stability and noise performance of amplifiers. It is a measure of the amount of signal that is fed back from the output of an amplifier to its input. Feedback Factor is denoted by α symbol.

How to calculate Feedback Factor of Low Noise Amplifier using this online calculator? To use this online calculator for Feedback Factor of Low Noise Amplifier, enter Transconductance (gm), Source Impedance (Rs) & Voltage Gain (Av) and hit the calculate button. Here is how the Feedback Factor of Low Noise Amplifier calculation can be explained with given input values -> 0.061224 = (2.18*23-1)/(2*2.18*23*8).

### FAQ

What is Feedback Factor of Low Noise Amplifier?
The Feedback Factor of Low Noise Amplifier formula is defined as a critical parameter that determines the stability and noise performance of amplifiers. It is a measure of the amount of signal that is fed back from the output of an amplifier to its input and is represented as α = (gm*Rs-1)/(2*gm*Rs*Av) or Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain). Transconductance is a measure of how much current the amplifier can produce for a given input voltage, Source Impedance is the opposition to current flow that the source presents to the load & Voltage Gain s a crucial parameter for low-noise amplifiers as it determines the amplifier's ability to amplify weak signals while minimizing noise.
How to calculate Feedback Factor of Low Noise Amplifier?
The Feedback Factor of Low Noise Amplifier formula is defined as a critical parameter that determines the stability and noise performance of amplifiers. It is a measure of the amount of signal that is fed back from the output of an amplifier to its input is calculated using Feedback Factor = (Transconductance*Source Impedance-1)/(2*Transconductance*Source Impedance*Voltage Gain). To calculate Feedback Factor of Low Noise Amplifier, you need Transconductance (gm), Source Impedance (Rs) & Voltage Gain (Av). With our tool, you need to enter the respective value for Transconductance, Source Impedance & Voltage Gain and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.
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