DaTajm is a wristwatch based on a PIC16F1824 powered by a single CR1216 lithium coin cell. I’m using a sandwich of three PCBs. The topmost pcb (0.8mm thick) have 12 leds and a resistive touchpad on the top side and all the other parts on the bottom. The middle pcb (1.6mm( is just a spacer for the battery. The bottom pcb have a contact for the positive pole of the battery and a soldered cable up to the top pcb.