Questions tagged [gain]
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 < 1)
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Opamp resistor arrangement to get out of its noise
In the balanced line technoloy text, the author mentioned that we can't have a large resistor for R1 in this circuit:
The author said:
For a series-feedback stage, the input impedance can be made as ...
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Effect of antenna direction on antenna gain
I'm studying antenna theory right now, and I have a question about the effect of antenna direction on antenna gain.
My assumption of the antenna direction is like below:
Since the Rx antenna cannot ...
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Common emitter transistor amplifier working in simulation but not in reality
I'm currently learning about transistor amplifiers. I've designed this CE amplifier circuit that should yield an ac voltage gain close to 100.
I assume my calculations where right, as it seems to ...
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How to find the gain of an inverting amplifier in terms of feedback?
I have been struggling to answer this question from The Art of Electronics where it asks me to find the closed loop gain of a non-inverting amplifer in terms of feedback and says that the derivation ...
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Discrepancy in theoretical vs measured gainbandwidth in LTSPICE ideal OTA
I am using a very simple model to show the unity gainbandwidth of a closed loop sample and hold with a closed loop gain of 2. One would expect an ideal OTA to have a GBW independent of rout as GBW is ...
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Calculating SPL in octaves from .wav file recorded with microphone in Python
I made a recording of my environment with a microphone with the following specs:
The recording has a sample rate of 44.1 kHz and a bit depth of 16. I use:
y, sr = librosa.load(latest_file, sr = 44100)...
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Voltage regulator equation
I'm designing a circuit using this buck regulator (AOZ2253TQI-20) from Alpha & Omega. Data sheet here, http://www.aosmd.com/res/data_sheets/AOZ2253TQI-20.pdf
The data sheet doesn't specifically ...
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NPN BJT emitter current only from base
I'm working with a BC637 transistor. I want to deliver a 48 V, 2.5 mA signal to my load (diagram below.) I have the load connected through the emitter pin (19.2k Ω resistor.)
I was under the ...
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Quantifying signal loss - should we use power gain or voltage gain?
We're researching communication with electrical signals through the human body (also called body coupled communication). We want to quantify the signal loss between a transmitter and receiver attached ...
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A/B power amplifier: difficulty getting a full output voltage swing
I have been designing an A/B voltage amplifier using the TIP31C/32C power transistors (schematic shown below.)
I have a significant loss in voltage gain which I haven't able to negate.
Is this ...
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Basic Variable Loundess Audio Amplifier
I am a beginner, looking to make an extremely basic variable loudness (gain) audio amplifier. I have a general idea of how a class A amplifier works, but I am not sure how to make one variable.
This ...
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Ideal behavior of op-amps [duplicate]
I have been studying about op amps and there is something I can't get my head around. The thing is, when assuming an ideal op-amp, one of the restrictions we obtain is that the voltage in both the ...
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How to find antenna gain?
Given:
Transmit power 1 W
Receiver sensitivity -95 dBm to -85 dBm
Frequency 2.4 GHz
distance 2 km
I have used Friis equation to compute it. I will use 2 similar antennas.
$$ P_r = P_t + G_t +G_r - F ...
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About Negative Gain in Bode Plot regarding the Op-amp Circuit Design and its Relationship with the Feedback Resistor
I am new to the circuit simulation and now I am using Tina to simulate a op-amp circuit for a photodetector. I have some questions regarding the bode plot.
Below is the circuit design, based on the ...
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Can this analog voltage be scaled and shifted to the new range using op amps with only ±12V power supplies?
I have an analog voltage signal which is in the range [+2.1875 V ... +2.8125 V], centered around 2.5 V. I would like to scale and shift this signal so that it is mapped to the range [-3V ... +3V], and ...
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LTSPICE: Dirty gate voltage and low gain - Hartley oscillator using MOSFET
I'm designing a Hartley oscillator using a MOSFET, but I have some issues. I've chosen L1 as 3 times L2 to obtain a gain of 3, however, it's more like 2.4.
First of all, I can't understand why the ...
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solving purely resistive DC circuit using input output impedances and gain
I want to solve the following example circuit not using node analysis or other methods but calculating input impedance/output impedance and gain of the circuit. The circuit has no AC source and is ...
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Op amp circuit gain analysis with multiple voltage source inputs [closed]
I've been doing small signal gain calculations, but I'm just stumped on this question. I want to solve this question on my own so any tips on how to analyze op-amp circuits with 2 voltage sources ...
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Thoughts on this single-stage BJT amplifier?
I've been self-studying electronics and am currently trying to design a high-gain single-stage BJT amplifier. Here is what I have so far:
Q1 serves as a current source "active load" for ...
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Does the antenna design equate to the range?
There are a ton of different antennas out there, here specifically I'm talking about directional antennas.
Options include Yagi-Udas, parabolic, LDAP, etc. antennas. All of these have somewhat of a ...
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Way of calculating Gain of Yagi-uda antenna at a particular location
Suppose that I have a 9-element Yagi-uda Antenna. My goal is to calculate the gain function of the antenna as function of zenith and azimuth angles, i.e. \$G\left(\theta, \psi\right)\$. As far as I ...
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Using an oscilloscope to measure the gain of an op-amp circuit (with capacitors)
I have an upcoming laboratory exam where we have to construct an op-amp circuit (from our experiments the circuits were always varied and probably will be a bit more difficult on our exam.)
We are ...
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Voltage gain of a differential amplifier with tail resistor
Suppose the following differential amplifier:
simulate this circuit – Schematic created using CircuitLab
To calculate the differential gain, I take advantage of node P being an AC ground and I ...
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Gain Value For Modified Differential Amplifier Circuit
I am trying to analyze the following differential amplifier circuit and am wondering how to calculate overall gain (it will be fed with two copies of the same audio waveform 180 degrees out of phase ...
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Output voltage at different output optical chopper frequencies
I have a circuit as shown in the figure and I am using it to extract output voltage of thermopile (to determine the time constant of thermopile ) at different output frequencies. The optical chopper ...
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How to increase CE amplifier gain to 12?
The gain needs to be increased to 12, currently it is at 10 but I cannot seem to increase this any more. The circuit topology cannot change, but the component values can - except R4, the 56 kΩ ...
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Friis Free Space Equation for Received Power
According to Friis Equation the received power is directly proportional to the square of the wavelength or inversely proportional to square of the frequency. But is this not misleading. There is ...
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Antenna radiation plot and negative gain values
In general, how to interpret the negative gain values on antenna radiation diagram plot? I have attached an example.
My guess is that they represent some value relative to some reference value. If so, ...
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Stable 94 dB gain op-amp amplifier
I would appreciate suggestions or best practices for designing a stable amplifier. My goal is to design a 94 dB gain low-noise op-amp amplifier for a 100 kHz signal with a bandwidth of 10kHz.
At this ...
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Gain of photodetectors
I found this in a lecture about "Optical Wireless Communications." It is slide 15.
Does anyone have idea how gain was computed?
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Voltage Gain Expression
I had a homework problem where I was supposed to find an expression for H(ω) = Vo/Vs of the op-amp shown below:
However, when I found my own expression, it turned out to be a very messy fraction that ...
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Why is the output of an Op-Amp given by the open loop gain multiplied by the input differential voltage
When designing op-amps at the transistor level, the op-amp output is given by:
vout = Aol(vinp - vinm)
where vout, vinp and vinm are small signal changes in the output and input voltages.
How come ...
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Why does gain of my INA2332 change with increase in input voltage?
I'm building an IoT circuit for sensing resistance change using Kelvin's 4 wire.
I have implemented a constant current source that supplies my two sensors connected in series with 50 mA. The output ...
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Problem with parasitic capacitor in feedback path in inverting circuit
I want to meet following conditions:
Gain: 27.74 dB
Input source resistance: 6800 Ohm
Bandwidth: 15Khz (I actually need to have a flat response until 10khz and I do not care about the rest of it)
I ...
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Why is CMRR defined differently in open loop and closed loop configuration of opamp?
I have recently been studying "Linear Integrated Circuits" and I am currently studying about opamp circuits. The books I am referring are Microelectronic Circuits (Seventh Edition) by Sedra ...
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Calculating the theoretical frequency response and static gain of a filter
I'm trying to calculate the theoretical frequency response and static gain of this low-pass filter. As far as my knowledge goes, calculating them using experimental means would be simple, but how ...
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Relationship between antenna impedance matching and gain
This is my first year designing and simulating antennas and I try to understand the relationship between impedance matching and gain. I stumbled upon the term of antenna efficiency which makes perfect ...
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Cut-off frequency of simple transistor circuit with capacitance between input and output
I have the following problem: -
simulate this circuit – Schematic created using CircuitLab
For the amplifier shown in circuit 1, the open circuit voltage gain at low frequencies was calculated ...
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Cascade BJT amplifiers gain calculation
I've been trying to cascade BJT amplifier to get a gain of 800. My input is 10 mV, and I want an output of 8 V. My question is, how does the gain of common emitter amplifiers work? I've created a ...
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Overall Gain for Mixer Circuit
I am working on an audio mixer circuit for balanced studio gear. The circuit consists of two unity gain balanced line receivers (THAT1200), going into a pair of voltage dividers controlled by a shared ...
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how to derive the DC gain of IPS stage?
I am reading Bob Cordell's book,Designing audio power amplifiers. And here is a basic 50-W power amplifier. Q1,Q2 compose a basic IPS circuit.
It shows how to derive the DC gain of IPS part:
The ...
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Why is there a minus on the voltage gain of a common emitter?
In a common emitter amplifier with \$h_{re}\$ and \$h_{oe}\$ unimportant, and a load $$R_{CL} = R_C//R_L$$ I'm studying the gain voltage
$$ A_v = \frac{v_{ce}}{v_g} = \frac{v_{ce}}{v_{be}}$$
So $$i_c =...
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Expected voltage on external gain resistor pre-amp
I want to build an amplifier with digitally controlled gain, using the THAT1510 pre-amp IC.
The IC provides two pins to set the gain, using resistors.
I want to switch between resistors with analog ...
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Gain of transimpedance op amp
I am trying to calculate the gain-bandwidth product of a project where I am reading photodiode output current measurements. I aim to find an op-amp to buy to use as a transimpedance amplifier. The ...
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Input bias current and offset current calculation for an LM741 op-amp
This is my circuit diagram:
The bias current of the LM741 op-amp is 80nA. The offset voltage is 1mV.
The LM741 has relatively large current offsets, voltage offsets and input bias.
I calculated the ...
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What is the small signal gain for this circuit?
The question looked easy at the first sight. I found the quiescent current through the BJTs.
I can say that |Vbe| = 0.7 V for both BJTs. Therefore, current through 1 kΩ below Q1 = 2 mA. Similarly, ...
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Calculating N-type enhanced MOSFET gain with two different equations brings me a different result?
Hi, take a look at this problem from my notebook. Leave alone the fact that the resistor should actually be 1,111.111, it is not related.
If they claim that VGS=2 and Vs is connected to ground it ...
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1-dB compression point is in the range of -20 to -25 dBm
I am reading the Razavi's textbook RF Microelectronics 2nd edition p. 18.
It says
1-dB compression point is typically in the range of -20 to -25 dBm (63.2 to 35.6 ...
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OP-Amp virtual gnd to real gnd gain control [closed]
Can someone please explain why a potentiometer from op-amp virtual ground to real ground control the gain?
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How can we find the voltage gain of a BJT circuit if the Vin and Vout are on different transistors?
I am trying to find the voltage gain of the circuit below. I drew the small-signal model for it (shown below). I know the formula for finding the voltage gain of a common-emitter BJT with and without ...
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