Arduino Micro D Pin OPut is 4V, causing relay to not switch correctly.


I am using Arduino Micro 5V , When i program Digital PIN x to swich Relay , It does not work the electricity does nbot pass through, The setup is correct.

I tested with Meter and it shows around 4.1 V flowing.

Tested same setup with Arduino UNO 5V , and VCC 5V worked fine , with 4.9 V flowing.

I this it has something to do with low V in Micro? What can be the solution to make it work.

Though relay shows light toggle but Electricity does not pass.

What relay are you using? Part number? (link to datasheet even better)

How is it wired? Can you draw up a quick schematic (hand drawn + photo is fine, please no fritzing - the people whose input you want despise fritzing). Most relays require too much current to be driven directly (you use a transistor, normally a MOSFET); if it was right on the edge before, switching to the 32u4 might be what did it - the 328p has slightly stronger pin drivers (compare fig 31-355 on pg512 of '328p datasheet with fig 30-20 on pg 378 of '32u4 datasheet) - but if you're right on the edge like that, you may also be exceeding the manufacturer specifications and may damage the chip.

A voltage does not "flow". Current flows.

Can a moderator move this to the proper forum section? This looks like an electronics issue, not an installation/troubleshooting issue to me.