I have an Uno and a Mega, and I decided to measure the voltage on the "3.3V" and "5V" power pins. On both boards, the "3.3V" power pins report 3.3V. But the "5V" power pins give strange readings: on the Uno, the "5V" reports 3.3V (as if it was the "3.3V" power pin), on the Mega I get 3.99V. Should I…

5V voltage on "5V" power pin? (Mega, Uno)

BabyGeezer June 6, 2019, 1:12am 2

have you got anything else connected ?
and i assume you are using a multimeter ?

Topic		Replies	Views
Nano input voltage IDE 1.x	6	1864	July 13, 2021
5V Regulated Power Supply: + to VIn or 5V Pin? Motors, Mechanics, Power and CNC	5	9286	May 6, 2021
Arduino Mega TX USB Voltage Question IDE 1.x	3	615	May 5, 2021
Getting only 3.3V at the 5V pin on an Uno IDE 1.x	4	1938	May 5, 2021
Powering the Uno via VIN with 5V Hardware	16	623	July 16, 2022