Questions tagged [op-amp]
An op-amp (operational amplifier) is a high gain analog voltage amplifier with differential high impedance inputs, and a low impedance output. A basic building block in signal processing, like as amplifier or active filter.
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How to offset PWM output so it would also have negative amplitude?
So PWM goes from 0 to 5V. How could I do -2.5 - 2.5V? Basically I am asking how to add offset to PWM signal. Should I use operational amplifier? How would I use it? I never had to deal with them, but ...
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Signal clipping in Arduino Serial Plotter
I would like to understand why did Arduino clipped the input signal as shown in the attached diagram? As far as I know, Arduinos are able to read analogue voltages up to 5v, that is 1023. But for some ...
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Mesure sensor voltage by 328p and OP Amp in parallel
I am designing a circuit to measure the temperature via a thermistor via the ADC pin on a 328p and I am looking for some advice. As a failover I am also using an OP Amp as a comparator, to see whether ...
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Reading ground signal from circuit
I am trying to detect whether a signal is high or low from an ESU LokSound 5 decoder for HO locomotives. My idea was to use one of the auxiliary pins used to drive an LED (AUX 3 in my case).
The ...
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Controlling op amps amplification ratio by arduino
Is there any option how to control amplification ratio of operational amplifier by some logic signal which can be produced by arduino? I am talking about some clasic op amp like lm356 or ui741 in ...
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Stable amplitude of amplified signal
Is there any circuit with opamp where can be (by arduino) set constant output amplitude which doesn't depend on input signals amplitude?
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Arduino IDE on Attiny45: What kind of power does a chip need?
I have this little AtTiny45 which I'm loading a program with Arduino as ISP.
My goal to use this chip along with a op amp, a piezo buzzer and a press button, and have it automatically sleep between ...
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Noise in Analog Read Serial from an instrumentation amplifier(ina122p)
I am trying to read the values from a simple EMG circuit (with an INA122P) using the analogRead() and plotting in the plotter using an Arduino nano v3. I am powering the ina1222p from the 5v pin of ...
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I am facing a problem of firing multiple interrupts on nodemcu 1.0 on single rising edge pulse.what is problem and what are the solutions?
I am working on a project which involves counting the drops falling in a drip chamber of a IV fluid gravity based therapy bottle(saline bottle).I am using IR trans-receiver at the drip chamber to ...
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Does using multiple HX711 amplifiers change the supply voltage of an Arduino?
I’m creating essentially a load cell using an Arduino Nano and an HX711 amplifier. However, I want to have two HX711 amplifiers running off the same Arduino. Will that change the supply voltage since ...
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HX711 - Inconsistent Readings
simulate this circuit – Schematic created using CircuitLab
Wiring is based on the scheme presented below -
(Reference: https://electronics.stackexchange.com/a/174580)
I am using Arduino Mega ...
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op amp circuit single sourced from arduino power
Getting an audio signal from a 3.5mm jack amplified (non-inverted) and fed into analog in pin on a Mega 2560. I am having problems using a potentiometer as a variable resistor to adjust gain. I'm also ...
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Arduino Nano Midi to cv convertor interesting issue
I created the circuit in this schematic on protoboard,
and the code,
https://github.com/elkayem/midi2cv
I use a dual opamp and a single dac, because i only need note and velocity.
The opto i use is, ...
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Oscillating Analog Readings
I am using a JIC 139 UV Sensor (datasheet) with an Arduino Mega 2560 and should be reading smooth curves as I bring a UV source to towards the sensor. Instead, my curves are increasing and oscillating....
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Amplify Piezo Sensor
I am trying to amplify a piezo sensor per the instructions found at the link below. I am not trying to trigger a buzzer only print to the serial monitor whether the vibration was detected or not. I ...
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