Tuesday, January 28, 2020

Seven segment display clock using Neon indicators.

Looking for a project to learn KiCad.

I love the color of neon and this design will use 5 per arm.

5 x 7 x 6 = 210.

I think I have 400 of them in a bag someplace.  Will use 6 latching BCD to seven segment ICs
CD74HC4511E . CD to Seven-Segment Decoder / Driver / Latch, HC Family, 7 Output, 10 mA, 4.5 V to 5.5 V, DIP-16
and discrete transistors to provide the high voltage drive.

The driver transistors are 20 bucks per hundred. The ripple counters are about ten bucks. I already have some high voltage power supplies.

DC-DC Boost Converter 8~32V to 45~390V High Voltage Charging Booster

I should see plenty of change out of a hundred bucks.

It will use 4 BCD GPIOs and 6 clock signals ...oops forgot the decimal points. Make that 11 output pins on the Arduino. Or I could go really agricultural and use an Arduino Mega with its 54 pins and drive each segment directly.

The challenging bit will be programming the Arduino. Deriving a timing reference and laying out the PCB in KiCAD.

I was trying to think of some artistic way of mounting the neons. Perhaps a copper wire trellis? Nothing seemed interesting. Just regular PCB makes sense and isn't getting too clever clever.