I have tinyduino loggers assembled from:
Processor board + accelerometer board + sdcard shield + protoboard connected to a DS3231 RTC
these units run fine from USB, and also from 2xAA unregulated power supplies connected to the external power pads on the processor boards
However when I try to power them (on the connections previously tested as good) using the Sparkfun's NCP1402 3.3V step up regulator (
https://www.sparkfun.com/products/10967) All I see is one little blip from the led on the processor board, when the power supply is connected, and then no further operation. The output from the voltage regulator seems to be stable at 3.3v when the tinyduino is connected to it.
I am not sure if this is some kind of inrush current problem causing a low voltage blip from from the regulator (causing brownout on the tiny), or excessive ripple from the sparkfun board, etc? Any suggestions on things for me to try?
Has anyone else run the tinyduinos from a boost regulator? I have sensors that need a regulated power supply for stable readings, so I am hunting around for solutions.