Simply the ratio of output signal to input signal, this dimensionless quantity is a measure of the amplification of a signal which may be represented by voltage, current of may even have a digital representation. A very general concept sometimes used to describe attenuation (when gain

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2
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2answers
44 views

Working with current feedback opamps [CFA ]

before entering in to problem: my application is a laser pulse detection, in this process when a laser pulse falls on photo diode it generates current, later stages include a I-V conversion, ...
0
votes
1answer
44 views

Finding Loop Gain (Aβ) of Transimpedance Amplifier

I have been having trouble finding the loop gain (Aβ) of the following transimpedance amplifier: simulate this circuit – Schematic created using CircuitLab To find Aβ, the books I have ...
3
votes
1answer
31 views

LC Oscillator Gain Compression

I am designing an LC Colpits common base Oscillator for the FM broadcast band. The project is going to be extremely low radiated power as I will only be using it in my car. I am currently using this ...
3
votes
1answer
89 views

Non-inverting and inverting gain of differential amplifier

simulate this circuit – Schematic created using CircuitLab From what I understand, the diagram above is of a differential amplifier and I understand them and how they work. But the ...
-1
votes
0answers
45 views

How to design a BJT amplifer with a gain of exact 100? [closed]

How to design a simple BJT amplifer with a gain of exact 100?
0
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1answer
22 views

Relation of Bdc with Ic [closed]

Following is a screen shot from Electronic devices by Floyd which describes that 'hfe' or 'Bdc' depends on 'Ic'... Now question is that Ic also depends on Bdc as by the relation $$ I_c = B_{dc} * I_b ...
1
vote
1answer
113 views

Measuring Open Loop Gain

I have a question about open loop gain. In the circuit below, I want to measure the open loop gain of the error op-amp. I'm curious if the Current Limiting op-amp will affect my gain. What does it ...
1
vote
4answers
68 views

Common Mode Gain BJT Differential Amp

I'm trying to determine the common mode gain and differential mode gain of the follow amplifier. Now I understand what the common mode voltage and differential mode voltages are, but I'm unclear as ...
0
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1answer
37 views

Stability of closed-loop systems at -180 degree frequency

Say e(t) is sine wave and y(t) is sine output. If y(t) has the same frequency as e(t) with phase shift of 180 degrees, we can only get stability of the system, if the gain of open loop at this ...
1
vote
2answers
67 views

T-Feedback Circuit Vo/Vi (Why is my approach wrong)?

Here's what I did. I know it's wrong but I cannot figure out why. Let \$V_s\$ be the voltage at the node between R2, R3 and R4. From the ground to \$V_o\$ terminal there is a voltage \$V_o\$ which ...
0
votes
1answer
35 views

Given input voltage and a set of output voltages of a second order low pass filter, how to calculate the gain of the filter?

I know that voltage gain = 20 log (Vout/Vin) dB, but the slope of the Bode s plot of second order low pass filter is -40dB/decade compared to the first order low pass filter with -20dB/decade. So ...
1
vote
2answers
78 views

Variation of voltage gain with frequency

For a transistor amplifier, the voltage gain (a) remains constant for all frequencies. (b) is high at high and low frequencies and constant in the middle frequency range. (c) is ...
0
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0answers
38 views

Differential Op-amp Circuit Gain Calculation

Having trouble with the second half of this question (b). How do you find the differential gain, when there is no Vout. *Edit: Attempt
0
votes
2answers
103 views

Single Stage Transistor Amplifier

so I have a question to build a single stage transisitor amplifier. I know Rc/Re = gain. And the value of capacitor which is parallel to Re can be found by the formula F = 1/2piRC but I have ...
1
vote
0answers
44 views

Inverting op amp gain using high value resistors and using oscilloscope measuremnts

I built an inverting op amp circuit as shown in above figure using varying values for Rf and Rin. When I used Rf=10kohm and Rin=100ohm, my measured gain (using national instrument's virtual ...
0
votes
2answers
77 views

op amp with single supply - non inverting circuit gain not being produced

I'm trying to boost a 12V signal to around 100-120V using an opamp from a single 12V 5A supply voltage (gain of about 10). I can't seem to get it to work though. Right now I'm just trying to make a ...
0
votes
0answers
37 views

How can I configure HFSS to analyze in frequency sweep?

I'm trying to generate a plot Gain(dB) vs Freq(MHz) with HFSS. I do know that it can be obtained clicking to "Create Far Field Report->Rectangular Plot" then select Phi and Theta, and all frequencies. ...
0
votes
1answer
86 views

Effect of Small and Large Signal Transconductance on the Colpitts Oscillator

I've been following Ron Quan's book: Build Your Own Transistor Radios and I've come to the section where Ron is analyzing the oscillator circuits used in his designs. In particular, he discusses the ...
1
vote
2answers
56 views

Approximate Gain vs Frequency Curve for an RC circuit

I'm trying to draw an approximate gain vs frequency curve for this RC circuit: I can solve for specific points, i.e. when \$\omega=\frac{1}{RC}\$ the Gain scale will be at -3dB but I'm not sure ...
0
votes
1answer
49 views

Amplifier Gain and Offset (Positive m and Negative b)

My question is regarding gain and offset of an amplifier. simulate this circuit – Schematic created using CircuitLab I've used various references however I believe the circuit I want to ...
1
vote
1answer
120 views

decreasing base current on saturated npn transistor

I would like to know if decreasing the current at the base on a saturated transistor(as in the attached photo) will cause the transistor gain to increase and by that, to maintain the collector ...
4
votes
3answers
537 views

Op-amp circuit has lower gain at low frequencies

I'm trying to design an amplifier, which amplifies line level audio to 5 Vpp, so I can sample it with a microcontroller. My plan is to do this in two steps: amplify the signal to 5 Vpp and ...
0
votes
1answer
42 views

pga gain formula

Background: I am dealing with reverse engineering a software. And trying to understand a formula in the code. I found a formula that reads: ...
0
votes
0answers
46 views

a question about gain equation of low pass filter

This webpage says: For a passive low pass filter, The gain equation is the RC potential divider equation: Here, They say: The frequency response of the circuit will be the same as that for the ...
2
votes
1answer
135 views

Mic preamp, fixing noise and gain issues

I'm trying to fix a preamp (made by a colleague) that's noisy and somehow not amplifying enough. I should say right away that this project is pushing the edge of my electronics knowledge so I have a ...
2
votes
1answer
115 views

Why Bandwidth Affects Response Speed

This is a follow-up question to (this question). Here is the amplifier section in question: In the answer, the author (@Brian Onn) gives the following explanation: "Slow vs. fast is not about ...
3
votes
1answer
115 views

Gain tuning issues of op-amp

I am currently building a simple gain stage with an op-amp (MAX414CPD+-ND) following this circuit diagram simulate this circuit – Schematic created using CircuitLab By adjusting the 10K ...
1
vote
1answer
71 views

Forced beta too small

Let's take an example in which the recommended beta for a transistor's(NPN) saturation is 10.If you use a forced beta smaller than 10,will the transistor still be saturated succesfully?Can hFE be ...
0
votes
0answers
58 views

Ziegler Nichols PI Tuning : Integral gain too high

I am tuning my PI controller in MATLAB using Ziegler Nichols method in which my plant is the car Engine and I have to stabilize the engine speed to lets say 900 when throttle is not pressed. In order ...
0
votes
2answers
68 views

How is the solution for \$\alpha\$ and \$\beta\$ current gain of a BJT derived?

I'm just an enthusiast, and not too good at maths; I'm exploring constant current source circuits, in doing so I came across two equations for BJT current gain: Could someone help me understand how ...
0
votes
1answer
79 views

A confusion on the current gain of an NPN transistor

In above screenshot V2 is increasing ramp voltage from 0 to 12V, which accordingly increases Ib. Transistor is an NPN type. Ic(q1) is the collector current. Vce = V1 is a constant 1V. So it means ...
-3
votes
2answers
99 views

No plot for DC current gain in datasheet

Here is the data-sheet: https://www.fairchildsemi.com/datasheets/2N/2N4401.pdf I want to use a 2N4401 NPN transistor in active region for amplification, and I want to know its beta(DC current gain) ...
1
vote
0answers
137 views

Did I mess up my lab experiment ? (active low pass filter)

This is the table of the readings and I have worked out the gain which is $$\frac{Vout}{Vin}$$ and I got all 5 at the beginning ... but I also remember that the values of the resistors in the feedback ...
3
votes
1answer
93 views

Wien bridge sinusoidal oscillator

simulate this circuit – Schematic created using CircuitLab I would check that in the Wien bridge sinusoidal oscillator the gain A_V=1+(R5+R4)/R3) is actually A_V=3 as the Barkhausen ...
0
votes
2answers
89 views

finding the gain of a two stage voltage amplifier

i currently do not know how to approach this question, in terms of simplifying the circuit and which formulas to use in order to find the gain
3
votes
2answers
60 views

average of dBs or dB of average?

In several papers, books etc. I have encountered to expression of "average gain of the path is ... dB", now I wonder this is the average of dBs or dB of averages? The sources have not mentioned ...
1
vote
1answer
67 views

unfamiliar gain equation of differential amplifier

I am examining op amps and I found this pdf very helpful: http://www.aicdesign.org/SCNOTES/2010notes/Lect2UP230_(100327).pdf In this tutorial, the op amp circuit topology is given as this: and ...
0
votes
0answers
47 views

midband gain calculation of feedback amp

I cannot wrap my head around this. how did they calculate the gain of Q1? can anyone explain the big picture? the math is already shown but I cannot see the breakdown of it. rpi1=2.3K and rpi2=1.23k ...
0
votes
1answer
46 views

Finding the voltage gain at low frequencies

can anyone explain how the second expression for the gain is obtained? they multiplied or divided the first equation and came up with second one.
0
votes
2answers
128 views

designing a variable gain amplifier

I want to build a variable gain amplifier. My first thought was to build two feedback resistors and switch one or the other off with a MOSFET. However, the MOSFETs have shunt diodes which are going ...
0
votes
2answers
65 views

What is the relation between the gain and range of a data-acquisition amplifier?

A data-acquisition amplifier has different ranges. The board amplifiers a voltage sample and ADC converts it to a digital code. There is probably a reference voltage inside the board so it compares ...
4
votes
1answer
285 views

Why Increasing Collector Voltage Reduces Collector-base Capacitance

I'm looking at some transistor radio circuits and the book I'm following makes the following statement with regard to AC gain: "By raising the DC voltage at the collector, the internal collector-base ...
1
vote
1answer
86 views

CE Amplifier voltage gain is not as calculated

Am trying to learn from what i read by simulating a common-emitter-amplifier using 2N3055A that has Bdc(DC Current Gain) of 20 - 70. I fallowed the steps below but the Voltage gain is not even close ...
1
vote
3answers
82 views

RF FETs - how exactly are they different from regular FETs?

I've browsed through DigiKey and there are these RF FETs. Are they for final stage amplification? Say you have an opamp that doesn't go for the final desired voltage, so one uses these FETs as Common ...
1
vote
3answers
146 views

Gain equation of cascode common emitter amplifier with an LC tank

I'm trying to find the gain equation of the circuit presented below. I know that for a cascode common emitter amplifier without resistor RE and with a current source instead of the LC tank, the ...
1
vote
0answers
187 views

Designing a Multistage Amplifier

I have to design a BJT multistage amplifier to meet a specification provided by my professor. The first stage is to be a differential amplifier, and the second stage is to be a common collector ...
1
vote
1answer
353 views

Why does the voltage gain of a transistor-based amplifier vary with input frequency?

Why does the gain of a MOSFET-based common-source amplifier depend on the frequency, and why does it vary the way it does? I did an experiment with a common source amplifier and recorded the gain ...
2
votes
1answer
90 views

Operational Amplifier gain bandwidth product

If the gain bandwidth product of an operational amplifier is a constant and |Vout/Vin| is also a constant does that mean that the operational amplifier will not function for all but 1 frequency? ...
0
votes
1answer
141 views

Audio Amplifier Design Questions

Consider the following system-level diagram of an AM receiver: I'm currently focusing on the baseband amplifier stage, which is used to amplify the audio signal. Its corresponding schematic is: ...
0
votes
2answers
166 views

Gain and offset adjustment with voltage reference?

I am building an instrument that relies on a precision sensor module. The sensor is factory-calibrated, and outputs 0-10Vdc. I believe the factory calibration to be better than anything I can attain, ...