Today we will discuss whether it is possible that we can power an Arduino using a 5V pin or this pin is only for output.
Arduino Power Sources
Most Arduino boards work on 5V supply. To power Arduino we have multiple sources. Three power inputs which is present in most of the Arduino boards are:
- USB Connector
- DC Barrel Jack
- Power Pins (Includes VIN, 5V & 3.3V)
Most of the frequently used source for powering Arduino is USB cable. Using the USB B cable, we can power Arduino from any USB port either using laptops, PC, power bank or mobile charger.
Second source of powering Arduino includes the DC barrel jack which comes in handy to power Arduino with rechargeable batteries in remote projects. Using this barrel jack any external supply or battery can be connected.
And finally, the last source for powering Arduino is using the on-board power pins. These pins include the 5V, 3.3V, and VIN pin. Best thing about these pins is that they act in a dual way. Either we can take power from them or use them in powering Arduino.
Can We Power Arduino Using 5V Pin
Yes! Arduino can be powered using on board 5V or 3V3 pins. These two pins work in a dual way they can act as a source for external peripherals like sensors and modules as well as can be used as a power source for Arduino boards.
These two pins can be used as a power source only when no other regulated supply is connected across an Arduino board such as using a DC barrel jack or USB cable.
We can use the 5V pin in two ways:
- Using external regulated 5V
- Using greater than 5V
Using External Regulated 5V on VIN Pin
We can directly apply regulated 5V on Arduino 5V pins. Before we can power Arduino with 5V pin following safety measures should be observed:
- Do not connect two power sources together
- Always use regulated voltage supply
- While connecting make sure to double check the wires polarity
- Don’t use this source if other sources are available
Using Greater Than 5V on VIN Pin
Arduino can also be powered up using greater than 5V but first we have to regulate that externally using any voltage regulator.
The below image describes the connection of a 9V battery with Arduino 5V pin and in between them a voltage regulator (LM7805) of 5V is used. This regulator steps down the 9V to 5V before it is given to Arduino power pin.
Why 5V Pin Is Not Recommended for Powering Arduino-Warnings
It’s safe to power the Arduino using a 5V pin however it’s not recommended. Because the 5V/3.3V pins are connected to the output terminal of the on-board voltage regulator and if a slight increase in current happens at the 5V pin there will be a large current flow from output terminal of voltage regulator to input terminal resulting in permanently damaged voltage regulator. Also, there is no reverse polarity current protection like in other power sources of Arduino.
Conclusion
Arduino has different sources of power including DC jack, USB connector, VIN Pins and 5V/3.3V pins. All other sources are safe to operate and use however 5V pin is not simple we have to keep the voltage and current requirements in mind before using it. We can use it for powering the Arduino however it’s not recommended to use 5V as input power source.
