Can Arduino Output More than 5V
No, Arduino cannot output more than 5V. Arduino is designed to work on 5V, one of the main reasons Arduino cannot give more than 5V is Arduino on board voltage regulators. Input given to Arduino is regulated by these voltage regulators. Arduino 5V linear voltage regulators allow Arduino board to take power more than 5V and these voltage regulators reduce it down to 5V. DC barrel jack and Vin pin are two input sources for Arduino that can take more than 5V, according to datasheet Arduino can handle up to 20V. But Afterall Arduino cannot output more than 5V because of voltage regulators.
To give a better insight of Arduino voltage calculation here are few highlights:
- You plugged a wall adapter into the AC socket and it will convert 220V AC to 12V DC.
- This 12V is input to the Arduino either using a DC barrel jack or Vin pin.
- These 12V are given to a 5V voltage regulator which reduces it down to 5V.
- This regulated 5V is supplied to a processor often called Vcc.
- Microcontroller is designed to work at no more than 5.5V hence it cannot give output more than the input 5V.
Arduino Voltage Regulators
Two types of voltage regulators are used in Arduino Uno and most of the boards:
- 5V (SPX1117M3-L-5) Regulator
- 3.3V (LP2985-33DBVR) Regulator
Both Vin and DC barrel jack voltage is regulated by a 5V regulator, however USB input voltage is by default 5V, so it is directly passed to the output pin. USB voltage is regulated in case of a 3.3V regulator to provide us with 3.3V output. Following diagram shows a graphical representation of Arduino two built-in regulators.
Arduino 5V Voltage Regulator
SPX1117M3-L-5 is the main voltage regulator of Arduino. It can take up to 20V and convert it down to 5V however it’s not recommended to put a lot of pressure on the voltage regulator by applying more voltage than the required optimum voltage.
The sweet spot for a 5V regulator is somewhere between 7-12V. Applying voltage lower than 7V can cause Arduino output voltages to fluctuate because some voltages are lost in heat dissipation while about 0.7 V is taken by diode for reverse current protection. Following table shows a brief description of limits about the 5V regulator.
| Regulator | Min Input Voltage | Max Input Voltage | Max Output Current |
|---|---|---|---|
| 5V | 6.2V | 20V | 1A |
Note: Applying more voltage across Arduino will cause regulators to heat up. Once the heat goes beyond the limit of the regulator it will automatically reset the Arduino board and will keep it off until the regulator reaches its normal state.
Arduino 3.3V Voltage Regulator
In older Arduino boards we need to power them using 3.3V as with change in technology 5V emerges as standard voltage for Arduino boards. Now all new Arduino boards have built-in 3.3V regulators to provide us with required voltage if needed. Also, older boards have too low current limits of up to 50mA but the new 3.3V regulators can go up to a maximum of 150mA. The new LP2985 regulator is a high quality and efficient regulator that can power stuff very easily.
As illustrated above this 3.3V regulator is connected to 5V regulator it reduces down the 5V output regulated voltage to 3.3V. Following table shows Arduino LP2985 regulator specifications.
| Regulator | Min Input Voltage | Max Input Voltage | Max Output Current |
|---|---|---|---|
| 3V | 3.58V | 16V | 150mA |
Conclusion
If we sum up today’s topic then Arduino can not give output more than 5V, maximum it can give is 5V. Microcontroller is the main brain behind Arduino as Atmel described 5V as standard operating voltages for ATmega328p, if we need more than 5V for external devices using Arduino then a separate power supply is recommended else Arduino will not handle this and may reset automatically.
