Battery powered PIR and temp/humid sensor

[tomkxy]

@Haakon Regarding the PIRs: There are a couple of postings in the Internet or I think even in this forum. For example, have a look here: http://randomnerdtutorials.com/modifying-cheap-pir-motion-sensor-to-work-at-3-3v/

[LastSamurai]

@tomkxy How did you power it though? I wanted to use a battery (or several ones) that might fall under 3.3V when used. So I decided to use a step-up converter but that seems to introduce too much noise, so I get false positives from the pir. From a stable 3.3V source it worked just fine.

[tomkxy]

@LastSamurai I powered it through 3.3v step up with one AA battery. I cannot confirm that I get false positives.

[martinhjelmare]

@tomkxy

What range on the PIR do you get on 3.3 V?

[tomkxy]

Around 4 meters. However, this puppy is sitting in my entrance which is rather narrow.

[LastSamurai]

@tomkxy said:

@LastSamurai I powered it through 3.3v step up with one AA battery. I cannot confirm that I get false positives.

Nice, what PIR and what step up did you use? Hopefully I can get the same ones too ;)

[tomkxy]

I used this one one which is rather expensive. I do not remember, however whether I bought really at Sparkfun or some other place. That were one of my first purchases when I started with all that crazy stuff :-)

[Mark Swift]

Hi @tomkxy

I'm going to add one of these sensors myself, looks like you've done the hard work...

Could I ask what board you are using, perhaps a simple schematic too if you find a moment? I have a bunch of Nano's, some light sensors (BH1750) and temperature sensors (DS18B20's) - I presume I can swap over the code as required. Thankfully I also have a number of those exact step ups!

[tomkxy]

@Mark-Swift I used a ProMini 3.3v. Unfortunately, I have no schematic. Since I used breakout boards anyway this is not a big deal. You connect those boards to your power, ground and a digital pin or on SCA, SCL pins. I don't know what the power consumption of the Nano's is. So that is something you have to try out.

[alexsh1]

@tomkxy it is a few mA while sleeping. This means that it has to be modified (no VDO and no LED) - consumption drops to a reasonable 160uA or even below.