Hello Tilman, this is really a very nice design. I have ordered a pack of PCBs from elecrow, based on your gerber files, and have a few questions:
in your BOM you have listed 5 smd-capacitors and 7 smd resistors, but on the PCB i have solderpads for 6 capacitors and 8 resistors. Can you just explain?
is there a uniflächentaster-model for 2 ways?
i think i have to flash the bootloader first, do you have a tutorial for this, and a sample-sketch for the board?
Thank you very much
Hi @tbowmo, do you mind to explain a bit about the design? I'm interested with your design.
I will use these steps for removing voltage regulator, http://goo.gl/CsZaNg
So the design will be battery > external step up regulator (http://goo.gl/PFt99R - to stabilize 3.3v) > vcc pin ?
with these then I can use my first post design?
Thanks
You can put 100uf on each even 200uf would not be able to handle only one tx, so..
but you need them at least for coin cells.
you would need more capa to handle tx..but the more capa the more time they take for recharging, and the recharging if big, increase internal res of the coin cell and that's not so good too; to prevent this that would need a current resistor limiter..etc a whole balance!
On mine for instance, I have 100uF for coincell, 100uF for PIR and 86uf on radio. Fresh varta coincell 3.02V, after multiple presentation tx 2.85V if I remember, not so bad. but that's an homemade pcb.
Another notes, it's better to use ceramic capacitor (because of leakage, if you want to optimize), and better smd, but that's not your case I think.
@epierre You can use a Peltier element to power this board. Like this one:
http://www.ebay.com/itm/TEC1-12706-12V-60W-Heatsink-Thermoelectric-Cooler-Cooling-Peltier-Plate-Module-/121349774916?hash=item1c41029e44:g:mukAAOSwDNdVrg-U
@4994james or just use internal vcc measurement as described on the same page. That saves you the voltage divider.
I wrote a convenient library to measure vcc internally : https://github.com/Yveaux/Arduino_Vcc
