An amplifier can be used to adapt the range of the signal to a requirement, to make it more robust for transmission, or to satisfy interface requirement (like input/output impedance)

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2
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1answer
39 views

Modding a Fender princeston chorus, having issues reading this part of the schematic

I am trying to add some wires for the left or right channel of this fender amp, and having trouble understanding the schematic here: There are 2 1/4" phono jacks on the front that are input no 1 ...
1
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1answer
34 views

What should be the output voltage for Virtual Ground to occur in Inverting OpAmps?

If I give 1v as an input to this inverting opamp, the output should be -10v just to make the difference between the input terminals 0. But when I solve the circuit using KCL for 1 volt input I get ...
-9
votes
1answer
61 views

Vs of an amplifier [closed]

Could anyone tell me what is the value of Vs in the image below? The input is a PWM with a frequency of 15kHZ and 0-3.3V level 50% duty cycle.
0
votes
1answer
49 views

I have one central 300w power supply running at 5v. How can I split this into 3 equal “ports” that use 20amps each

I have one central 5v 300w power supply. I want to basically split the power among 3 different ports instead of blowing the whole 60 amp load. How can I share the power evenly. Thanks!
0
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1answer
51 views

Can I use arduino to feed this circuit instead of an external power source?

I am following this tutorial to connect the output from my guitar with arduino. I'm wondering: is it possible not to use the batteries, and to feed the circuit with the 5V output pin provided by ...
-5
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0answers
26 views

How to wire speakers to amp [closed]

I have two 4 ohm speakers that I want to wire to an old Kenwood KA-5020 amp. What happens in terms of impedance if I wire the left speak to the Right (A) and left speaker to Right (B)? Other than it ...
1
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1answer
43 views

Cost Effective Solution to using PAM8403 as a headphone amp

I've just bought a PAM8403 pre-built circuit board for $1 on eBay, I was going to use it to drive a set of headphones but I neglected to consider that this is a Class D amplifier and will not take ...
0
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0answers
21 views

Biasing an SPD with a current source

While looking for an approapriate way to bias an APD (a SPAD), I've been suggested to use a simple constant current source (by means of a depletion MOSFET and a resistor) instead of voltage regulator. ...
4
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3answers
529 views

Expressing Gain in Decibels?

1) Why does power gain use a coefficient of 10 unlike the other two? 2) Why can't power gain be negative?
2
votes
4answers
297 views

Switching resistances in op-amp amplifier

I am building an inverting amplifier with an op-amp to attenuate a signal (ie: gain < 1) and I would like to be able to change the gain electronically by connecting multiple resistors to a switch ...
2
votes
1answer
55 views

Turning on circuit when headphones are inserted

I'm using a split supply, using 2x 9V batteries for a headphone amplifier. In lieu of an on off switch I'd like to just turn on or off when I put in the 3.5mm jack. Unfortunately the female jacks I've ...
0
votes
1answer
49 views

Difference Amplifier Design

I have two signal voltages V1 ranging from 100mv to 600mV and V2 ranging from 100mv to 600mv. I want to implement a difference amplifier using this opamp 601 which is a single supply CMOS. My Vdd ...
1
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0answers
36 views

Region of Operation of MOSFET and current cutoff frequency

The current cut-off frequency for a MOSFET is defined as the frequency at which current gain (ratio of drain to source and gate to source current) is unity. Can we use MOSFET as an amplifier at ...
1
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1answer
42 views

TDA 2030 emmiting voltage to Line in

i've build 15w amp from TDA 2030 but currently i measure from input line to ground (measure are performed from audio jack), reaching 400 mV, my question is: -is that normal? how i can remove it? even ...
0
votes
3answers
84 views

Instrumentation Amplifier Level Shifter

I am working on a temperature measuring circuit using a pt100. The input of my instrumentation amplifier (AD8226) is between 80-200mV. The Gain is set to 20.84 so I get an output range of 1.7-4.2V. I ...
-1
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2answers
69 views

Differential amplifier advantage in IC manufacturing

Differential amplifier will overcome need of blocking, coupling, and bypass capacitor present in normal amplifier made from single transistor. Hence, all IC contains majorly this differential ...
0
votes
3answers
53 views

How to convert noise to noise density in mic pre amps

I am trying to compare two low noise mic pres for the lowest noise, and I am looking at the TI1012 and MAX9814 MAX9814: ♦ Low Input-Referred Noise Density of 30nV/√Hz TI1012: Output Voltage Noise ...
0
votes
2answers
76 views

differential amplifier will cancel DC present at input

In differential amplifier, it is written that "only AC signal will be amplified and DC part at the input will be canceled and hence there is no need of DC blocking capacitor". I am not getting this ...
5
votes
3answers
325 views

How can an op-amp act as a precision diode?

I read in an article on application of op-amp that it can act as a precision diode. Precision diode is an ideal diode having very much less forward voltage drop. I am not able to understand this ...
0
votes
1answer
50 views

filters for in-amp, difference amplifier, and non-inverting op amp

I am new to this matter and would like to learn how could I determine the right filters to use for my circuit. I have read some tutorials about active and passive filters but can't get the right ...
-1
votes
0answers
39 views

Designing an inverting amplifier with a given gain, open loop gain and gain bandwidth product

How do I design an inverting amplifier with a given gain, open loop gain and gain bandwidth product? For example 12dB gain, 86dB open loop gain and a GBP of 500kHz? Using the gain formula I can ...
1
vote
1answer
75 views

Why does non-inverting input of non-inverting amplifier need a path for DC to ground [duplicate]

Wikipedia says that, but doesn't give any explanations. The non-inverting input of the operational amplifier needs a path for DC to ground; if the signal source does not supply a DC path, or if ...
2
votes
1answer
88 views

Would an RF amplifier be required for an indoors antenna connected via coaxial cable to an outdoor directional antenna (900/1800 MHz)

Sorry, couldn't make the question title any shorter without losing meaning. So, I'm looking to build an outdoors yagi antenna that's connected to another indoors antenna via coaxial cable. The ...
2
votes
1answer
66 views

What's the error in this simulated amplifier circuit?

I have attempted to simulate (using Circuit Simulator) an IC amplifier circuit (the LM386-3) based on the schematic reference manual. Here is the schematic: and here is my simulated version: On ...
0
votes
2answers
63 views

Purpose of gate driver in Class D amplifier

Can somebody explain to me why we need MOSFET gate driver in class D amplifier like in the picture below(common class D schematics)? What I don't understand is if we for example have 9V rails, then ...
2
votes
2answers
109 views

Why does this analog front end EVM have 4 pins per channel, instead of 2?

Here is a photo of the ADS1299 EVM from texas instruments. It is an 8-channel low noise analog front end chip. I understand that for each channel, the potential difference between plus and minus are ...
1
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4answers
81 views

Analyzing an op amp circuit (transfer function) that does not match the basic cases

At the following circuit I want to find what it does and basically its transfer function. I've searched a lot but I didn't find any circuit like this. Since it does not match any of the basic types of ...
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votes
1answer
132 views

What is the best suggested way to amplify the voltage and ampere of a signal coming out of a microcontroller and keep wave form as it is?

I am generating semi-pure sine wave voltage signal out of an AVR microcontroller. The thing is I want to amplify this signal (power amplification [voltage and current]) with keeping wave form as ...
1
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1answer
93 views

Electret microphone amplifier - Terrible low frequency response

I have tried to design a amplifier for an electret condeser microphone. It is basically just a common emitter NPN amplifier. The problem is the frequency response of the real circuit. I get the ...
3
votes
2answers
207 views

Car radio output voltage

I am working on an amplifier for a car radio for a friend of mine. He is away for few weeks so I can't measure the radio output. That's why I am asking here, does anyone know, what's the ...
0
votes
1answer
81 views

How do I decrease phase margin of an op-amp?

I have designed a CMOS op-amp circuit like figure The problem is the phase margin is 79. How can I decrease phase margin to 60?
0
votes
1answer
52 views

Question about MOSFET CS amplifier simulation

This is the project statement: I have designed the circuit and it worked well. This is the circuit: It contains 3 voltmeters and 1 ammeter as shown. This is a plot for ...
1
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2answers
75 views

Class D amplifier woofer filter designs

I am working on a 140W class D amplifier for my subwoofer. I am familiar with its topology but have few questions. The music source is a radio that ouputs 200mV peak-to-peak signal containing all ...
0
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0answers
21 views

Load cell Sensitivity

Is there a way that I could exactly know what is the value of the sensitivity of a load cell(mV/V)? The only characteristic I know is its full capacity which is 200kg and written on the sticker. I ...
0
votes
0answers
51 views

Driving a 60W 28Khz Ultrasonic Transducer

I am trying to find a circuit diagram to drive a 28Khz 60W ultrasonic transducer. Preferably, it would be DC run and be able to power the transducer at full power for at least 5 to 10 seconds as a ...
2
votes
3answers
185 views

Analog preprocessing circuit (anti-alias/pre-amp) for driving ADC

Background Similarly to what Jeri Ellsworth did in her C64 Bass Guitar hack I am working on an audio-to-midi converter for my bass guitar. I am also planning to use piezo discs as sensors placed ...
0
votes
1answer
76 views

using AD620 with load cell

I am currently using an AD620 to amplify the signal coming from my load cell. I am supplying it with single supply of 5V and 0V. Below is my preliminary circuit. I am feeding half the supply to the ...
0
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0answers
40 views

Rf amplifier in AM receiver

I have an Analog electronics class project about AM receiver. In the project, it is stated that RF amplifier will be used after antenna. What kind of amplifier is this RF amplifier, voltage, current ...
0
votes
2answers
79 views

No output from Transimpedance Amplifier

I'm trying to set up a transimpedance amplifier reading the response from an avalanche photodiode (Hamamatsu S12572-100P http://www.hamamatsu.com/resources/pdf/ssd/s12572-025_etc_kapd1043e03.pdf) and ...
0
votes
1answer
43 views

Cross-over distortion thanks to short circuit protection

I am trying to build a AB Amplifier for school with some darlington transistors. Everything seemed to go fine until I added the short circuit protection. From that moment a cross-over distortion ...
1
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1answer
60 views

Designing and simulating a common source amplifier circuit

This is the problem: And this is my design for R1 and R2: So, using B2 Spice simulator I made this circuit according to the design: Vin_ and Vout_ are voltmeters. But the problem is that ...
1
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0answers
49 views

Self-oscillation in a commercial RF amplifier

I purchased several 50 ohm (in/out), 35 dB gain photomultiplier tube (PMT) amplifiers from a vendor assuming I could use them to read out the voltages on my PMTs. The amplifiers are AC coupled with a ...
-4
votes
1answer
96 views

How to wire subwoofer to 2.0 channel amplifier

How to wire the sub-woofer amp to existing 2 channel amplifier? I have dual LM386 for left and right channel and I would like to connect a sub-woofer. where should I wire the sub ? Is it in the ...
0
votes
1answer
83 views

AD620 with load cell help!

I have bought a 200kg load cell and an AD620 in-amp. I only want to use 100kg as the maximum weight capacity. I want to power the load cell and the in-amp from the 5v pin of the arduino. The seller ...
2
votes
4answers
202 views

NPN BJT base->emitter resistance is effectively zero?

I've been trying to better understand BJT transistors. In particular I've been trying to understand the inverting amplifier configuration. Wikipedia shows this schematic: Which shows an input ...
0
votes
1answer
65 views

PSPICE Simulation of Cascode Amplifier Not Working

Can anyone please tell me why I am getting the following "floating node" errors. I have fiddled around with the resistors to see if it affects anything, so these are not the actual values. I have also ...
1
vote
2answers
83 views

5-12v ~15w simple class a audio amp & build to 2.1 pc speaker

is there any IC that take 5-12v input and 15 w output class A amplifier for 2.1 ch pc speaker?(can be mono amp) because i've search google and found ic that only take more than 15v DC power supply, ...
0
votes
2answers
72 views

DC output of differential amplifier with active load

I've been looking around for some kind of explanation on how to get the output DC voltage on a single ended differential amplifier with active load like the one in the image It's just that i don't ...
0
votes
0answers
45 views

Common Drain Design Not Meeting Spec

I am trying to design a Common Drain amplifier with specifications below. I have reworked the problem over 10 times now and have not achieved anywhere near an appropriate solution. I have spelled out ...
0
votes
1answer
70 views

Bias-setting on valve amplifier with dual negative bias supplies

This is a general question, although the immediate purpose is to apply it to a Thorens AZ-25 amplifier from the 1960s. Schematic is here. Push-pull valve (tube) amplifier output stages are generally ...