Does the Pro Mini flash if underpowered? (1xAA + Step Up)

[chbla]

Hi there,

I'm experimenting with different setups, and for a door sensor tested:

• Pro Mini 3.3V/8mhz clone
• 1xAA (eneloop)
• Adjustable step up converter: https://www.pololu.com/product/2560

I noticed after a while the arduino LED (outer, marked with L) starts flashing at around 1HZ and it doesn't transmit anymore.
The voltage is at 3.3V, battery voltage around 1.4V.

Does anyone know what causes this? Is it maybe not getting enough power?

[chbla]

anyone an idea?

[AWI]

@chbla As long as the mini gets enough voltage (3.3v) it should keep working as expected. We need some more details (wiring, sketch) to help you diagnose.

[chbla]

I figured out it seems to be the voltage regulator - if I connect directly or with a 3.3v power supply, it works... very weird

[gohan]

Is that both a boost-buck regulator? Did you try adding a capacitor to the output? maybe it is a little unstable and the pro mini doesn't like it