The microcontroller uses MCS-51 series 89C51 (one piece), 74LS244 and 74LS373 (one piece each), inverting driver ULN2803A (one piece), and operational amplifier LM324 (one piece)
2-layer PCB 8.89 x 19.05 mm FR-4, 0.8 mm, 1, soldered with leads, white solder mask, black silkscreen