Originally Posted By: tfabris
what I'm trying next is just ordering a different Pololu voltage regulator that is pin-compatible but outputs 6v for the Arduino VIN pin.


Sounds good. Except you'll want 6.5V (minimum) output, not 6V. Per the design recommendations in the datasheets linked above.

Originally Posted By: ams117 datasheet
The dropout voltage of the device is guaranteed maximum 1.3V

Which means it guarantees correct operation (of the Arduino board's 5V regulator) under all conditions only when the input voltage is at least 1.3V higher than the desired output voltage. So for a 5V output voltage, it requires 6.3V or higher as input.

It will "happen to work" with lower input voltages at room temperature, with a light load. But as you seem to be concerned with the huge swings in temperature that regularly occur inside a vehicle, one really needs to keep it fully in-spec.


Edited by mlord (12/01/2018 12:05)