Digital Fever

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Rotary LED Blinker

1 Introduction

Basic digital circuit can start with 555 time

While CD4017 Decade counter can drive 10 output  and it can count from 0 to 10 with internal logic

The output waveform shall be,



2 Schematic Drawing

When NE555 time give timer pluse, the CD4017 can drive the LED on the ring one by one. Here is the schematic drawing.


3 PCB and Design

Here is the final result for the PCB and design. NE555 in SOP8 and CD4017 in SOP16

4 Summary

Q1~Q4 are thyristor to allow wider range of input voltage, this part is not show in shematics. D1 is inverted signal for D1~D10 around the ring.

This make the leds blink around the ring  one by one.