This circuit is a simple driver for seven segment display without using any IC.
It can display 10 numbers, from 0 to 9 depends on the position of the header jumper.
Parts List:
LED (35pcs)
SMD transistor 1AM (7pcs)
SMD Diode M7 (21pcs)
SMD Resistor 470 ohm (7pcs)
SMD Resistor 10K (7pcs)
Header Jumper (10pcs)
Male pin (2x10)
Battery Connector
Circuit:
You can use the traditional common cathode 7-segment display (0.8 inch or bigger) instead of 35 pieces of 5mm LEDs !
You can order this PCB from here:
https://www.pcbway.com/project/shareproject/W158454ASS94_Gerber_big_7segment_17037bec.html
Video:
