Arduino Stack Exchange
Arduino Stack Exchange

Questions tagged [voltage-level]

Voltage level should be used for questions that are referring to using hardware together that operates on different voltages (the "concentration" of electricity).

292 questions
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What are the 5V and VIN pins for?

I believe I can supply the Arduino with power in three different ways: Use USB. The design trusts the 5V to be regulated, and does not regulate it in any way. Use a regulated power source, trusted to be 5V, and connect it to GND and 5V. Connect…
Mads Skjern
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How to identify Arduino Mini Pro 5v vs 3.3v

I have many Arduino Mini Pro, every from different seller. Few are 3.3v and most 5v. I had to clean table for Xmas and now I do not have any idea how to identify 3.3v Arduinos. They do not have any marks. I bought them on ebay. I know 3.3v has 8mhz…
Max
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Power supply voltage confusion

I just ran into this article: Arduino: What adapter?. It says that the external power supply should be 9-12V. That really surprises me, since my Arduino Uno can also be powered via USB, which is 5V. Later he talks about a 9V pin. But I can only see…
Mads Skjern
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8
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2 answers

What maximum length of wire can I use to connect a push button to an Arduino?

I am trying to get 8 stop buttons to cause an Arduino UNO to activate a single relay! The stop buttons have been placed 30' to 250' away from the Arduino uno board. Q: How far can you go with 5v and still get signal back? Q: Is there a way to…
The Earl
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Level detection of 3.3V from 5V arduino

A quick question about microcontroller digital level on I/O pins. I have a photo interrupter which is powered at 3.3V which is interfaced to Arduino UNO running at 5V. For microcontroller to detect high or low level is determined by signal higher…
David Norman
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How to switch a low-voltage (1.5V) toy motor with an arduino?

I would like to add an Arduino to control a toy with a 1.5V battery and motor in it. The toy is currently controlled by a SPST switch in series with a single 1.5V AA battery and a cheap motor. I could put in a transistor like How to switch an…
Dave X
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Level shifter with diode - not pulling to zero

I'm interfacing a 3.3 V device (a GPS module with a serial interface) to a 5 V Arduino Nano. The circuit I am using is this: simulate this circuit – Schematic created using CircuitLab I don't have the GPS Module connected at the moment and have…
RedGrittyBrick
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MKR WIFI 1010 Providing 3.3V to breadboard

The Arduino MKR WIFI 1010 product page says "The microcontroller on the MKR WIFI 1010 runs at 3.3V, which means that you must never apply more than 3.3V to its Digital and Analog pins. Care must be taken when connecting sensors and actuators to…
Dan
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Using 5V microphone module with Wemos D1 Mini Pro 3.3V analog pin

I want to read values from this microphone module using Wemos D1 Mini Pro analog pin. Unfortunately, this module operates on 5V, but the analog pin on Wemos has range 0-3.3V. I have tried to use a voltage divider on microphone module output, but I…
jirinovo
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Arduino 101 I/O voltage levels

As per the Arduino 101 schematic. The Arduino 101 has level shifters (TI make LSF0108) connected to the I/O ports I guess these are to make them Arduino compatible(5V) since the Intel Curie Module is 3.3V rated. I have 2 doubts regarding this The…
Miguel Sanchez
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Fan dropping voltage?

I have students using an arduino to control a fan. We have multiple types of fans. We want to turn the fan off/on with digital HIGH. When the 5V fan is plugged into 5V and ground, it runs. When I ground it and attached the power side to a pin set…
Faith
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Programmed 5 Volt output to power a relay

I need to put out 5 volts from an Arduino UNO digital pin. I've read that the pins can do approx. 5 volts, but I need to know if it will actually reach 5. I'm also powering a few other devices from the Arduino. Are the digital pins capable of…
SeanM
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Reading temp data

I have hacked this kettle so that I can turn it on and off remotely via wifi and that is working perfectly. Added this to get a better signal. This is my micro controlling the 5v buttons on the kettle. I keep running into a wall when it comes to…
futurebird
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