This is a very thin and compact board I designed for recessed contact door/window sensor with vibration/tilt detection.
But it could also be used for:
Mcu : NRF52832 with optional onboard inductors for DC/DC mode for lower power mode
Accelerometer : LIS3DH
Hall Effect Sensor : DRV5032 (for detecting a recessed magnet)
Coincell : CR1632 (with 100uF capa for buffering)
Whip (external wire) antenna
smd pads for reprogramming through SWD
Parts size : 0402
Size : 18mm diameter for 19mm (3/4) drill
Expected battery lifetime : 2 years based on 40*2 events per day
Special thanks to
Copyright Scalz (2017).