Like a lot of people I'm building a little transmitter unit with one of those cheap 433mhz transmitters and an ATTiny85, and I am having a problem with the power supply. Actually it is only the power supply, everything else works nicely. But my battery is dead my morning, where 'dead' means under 4v and the circuit no longer works.
I initially tried with three AA batteries to power both RF and ATTiny. That worked but the range was not as good as I need. I got about 30m using 17cm whip antennae on both transmitter and receiver. That doesn't reach my letter box :)
Moving the voltage on the transmitter up to 12v did wonders for the range, but the ATTiny doesn't like more than 5.5v so I put a 7805 and some caps in there (the caps improved the range too) and ran the transmitter directly from the battery and the ATTiny from the 5v battery. That worked really well. But that sucks the battery, which is my current problem.
The battery I'm using is a 23A, about an inch long, alkaline 12v. It keeps the device quite small.
I would delete the 'out of regulation' but keep the 'low batt' signal if I can, I had that working on the earlier 4.5v AA version of this. I think it means I need to change the voltage divider on the left. What I've read is that the LP2953 ought to be smarter about sucking battery, though I also notice in the data sheet they recommend hooking the designated pins to a copper base on the PCB, so if it is dissipating heat that means it is still sucking my battery isn't it?
Given this is my third try at powering this thing any advice is appreciated. The receiver end has another ATTiny85 hooked up to a Beaglebone and that all works nicely.