I have an idea of slicing a 5V supply to a pyroelectric sensor circuit, and putting a time/annual switch in between.
Why?
I need a hard reminder for recalibrating that sensor 4 times a year, but I am able to put such a switch in a tight space only so size is an issue.
Sensor is a part of a big system, and when left without power will set a flag and therefore remind me to recalibrate it.
System is turned on 1-2 times a week, so the RTC will have to keep track of time while on battery.
Why do it like this? - well to learn something more about EE, especially PCB manufacturing since I'm a total noob here.

Idea goes like this: RTC keeps track of date, MCU checks if it is that time of the year (I2C) and if yes switches off the relay.
Primary concern is the switching off moment from my noob point of view, that is why I added 100uF cap to help out (noob gut instinct).
Also I want a fail-safe design, meaning if anything is bad with the circuit (pcb, soldering, elements...) my pcb will forward 5V to the sensor, so basically I want NC relay, but since they are slim picking just went with a SPDT.

Choice of elements is based mostly on the stock at a local store, far from DigiKey/Mouser, but I get it in a few hours.

Attached is the schematic and pcb layout.
All critiques are welcomed, especially negative ones, but please elaborate on why something is bad here.

Thanks!
View attachment 125887 View attachment 125888

 

Somehow I messed up upload of PCB layouts in the first post and can't correct it, two layers:

 

I see this as basically a 91 or 92 day timer. My first question is how does the START time get set?

That fancy RTC needs to be set somehow.

 

Well for now yes it is a 90ish day counter, but the MCU allows more options for some future mods.
Regarding RTC setup, I'll either add I2C pins to the board or use a soic16 clip and then externally setup the time over I2C. I'll use it for periodic checks also.
Well that is the idea.