Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [dc-amplifier]

10 questions
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Minimum voltage for DC amplifier

Based on Detecting a low pulse from an electromagnet induction, I was planning to amplify a DC sine/sqaure wave, however the peak is less than 50mV. What is the smallest voltage peak that can be amplified using a DC amplifier?
Sherby
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Are direct coupled audio amplifiers still produced?

I am searching for an inexpensive option to drive a magnetic coil with a frequency in the range of 1 Hz to 1 kHz. DC audio amplifiers, such as a Crown 300A-DC Series II or a Mitsubishi DA-A15DC, are perfect for this purpose. However, is there still…
Felix
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Does Transistor NPN only amplify Positive charge?

I know my question might be a bit "stupid", as I am now a student. I created a circuit like this ... But it does not work. (I mean the DC Motor does not turns.) simulate this circuit – Schematic created using CircuitLab (The DC Motor I can't find…
Walt Peter
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What OP AMP spec should I be checking to assure this behavior

Recently, on the advice of others on another thread, I tried to migrate a dual supply OP amp circuit to single supply version. I needed a quad OP AMP, and the logic was that since my final circuit only needed to provide 0 to about 3.5 VDC, an LM324…
Randy
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DC amplifier to turn sensors analog signal into 0-5V

I'm using a controller that needs a 0 to +5V input to activate an actuator on the output side. Normally, a potentiometer of 10k is used to delver 0-5V on the input (left drawing). For my application, I need to control it with a sensor that acts as a…
MarcC
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Current sense amplifier working principle

i am running a bldc motor Infineon TLE9879 chip. Now i want to measure the current flowing through the motor. so i use the current sense amplifier where the motor current is converted to a voltage by means of a shunt resistor RSH(0.005 ohm). I want…
litun bls
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Transistor letting 12Volts through collector->emmiter withouit being damaged

I have made a simple digital amplifier using 2N4401 Philips switching transistor. simulate this circuit – Schematic created using CircuitLab I have tested this amplifier on 5 VDC and it has worked (though the effect was very weak). However, if I…
Tomáš Zato
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Why doesn't a normal npn transistor with common emitter configuration, in active mode, not behave as a DC amplifier?

If a normal npn BJT transistor amplifies the base current (DC) to beta+1 times (the emitter current = (beta+1)*(the base current), why can't we call it a DC amplifier?
Mansi
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AC/DC amplification

I'm kind of new to this and hope someone with more experience can give recommendation or even a schematic suggestion. I have one function generator (Agilent) and one DC source (Agilent). The signal generator is set to send out a signal of 180KHz…
AKE
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How to build a DC amplifier using opa552

I am working on a project which requires me to amplify a dc supply volatge of 2v to 20v. I used the opa552 op amp with an input resistance of 100 ohms and a feedback resistance of 1k ohm (i.e., Rf/Rin = 10 is the gain). However I wasn't successful…
Sowmya Vidiyala
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