I have what seems to be a fully functional ArduIMU v2. I can program it via Arduino IDE and see the output on the serial console. Everything seems to be working quite fine but there is a peculiarity that I have not been able to reconcile.
When I measure the resistance between VCC (5V) and GND (ground) I get a reading of 34 Ohms... in fact, the multi-meter catalogs it as a short circuit. Furthermore, if I measure the current consumption of the board, once it finishes the ground start routine, I measure roughly 145mA. The peculiarity here is that if there WAS a short, I would expect 147mA due to the short in addition to the power consumption of the 3.3 regulator, sensors, ATMega, etc. yet all I measure is 145mA.
Does anybody know why there's I'm reading such a low resistance between the power rails, yet have what seems to be a functional board?
Measuring the resistance across 5V and GND on several pins for one of our ArduIMU's here at the store, the resistance is hundreds of kilo ohms. It could be a faulty capacitor on your board, shorting but not fully. If you have something with a very low resistance on the board, it will work, but it will draw a lot of current.
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