as mentioned in the subject, I have a problem with the Vin Pin on my Arduino Mega.
Background:
My project is a mobile robot with 4 dc motors + sensors + drivers and a mega. Power source is a lipo accu (max: 8.4V min: ~7V). The mega is supplied directly over the Vin and GND Pins - measured voltage: 8.4V. The mega showed strange behaviour and restarted randomly. So I measured the voltage on 5V and GND Pin -> only around 3V (or less). If I supply the mega over the usb-port, everything is fine (Voltage around 4,9V). So I guess, there is something wrong with the voltage regulator on the mega. Some weeks ago, I had a short circuit in the system (around 1s), which let the voltage regulator smoke a bit ... but afterwards it was still working.
I also noticed, that the voltage on 5V rises from 3V to 3,5V if i press the reset button ?! :o
My questions:
Am I right, that the voltage regulator is damaged?
Can I easily (and cheap) swap/fix it or do I need to buy a new Mega? (Power supply over usb is not a option)
Does the dc jack also "use" the voltage regulator?
Other ways to bypass the voltage regulator?
notmyname:
My questions:
Am I right, that the voltage regulator is damaged?
Can I easily (and cheap) swap/fix it or do I need to buy a new Mega? (Power supply over usb is not a option)
Does the dc jack also "use" the voltage regulator?
Other ways to bypass the voltage regulator?
Yes, if it smoked it's functionally dead whatever output it still manages to get.
You can solder a new one - there are probably cheap replacements on ebay or something.
Yes, the power from the DC jack goes through the regulator
Bypass - only if you can supply stable 5V directly to the 5V pin, or get an external regulator of some sort...
... but afterwards it was still working.