[John Sarik] keeps cranking out new ideas for his digital Sudoku project. This time he’s using 7-segment displays for each digit. The game play works the same as the Nixie Tube version, but this makes things quite a bit easier to build. The board above is one of the nine modules that make up the game. They each use three shift registers to drive the nine 7-segment displays. With the help of five resistors all of the multiplexing is addressed via the serial input on those chips.
9!!?!? wow
minuturised it would make a great key fob!
I really like the layout on this one. Well thought out.
Too bad Freescale’s MC14489B is almost $5 in onesies. It’s a 5 digit 7 segment display driver that talks over SPI. The advantage is that the digit drive transistors are scanned from an internal clock so you don’t have to constantly drive out an SPI signal. That and you can ditch the transistors and cut the number of ICs to 2.
@chango Thanks for the IC recommendation. It’s hard to find drivers that aren’t designed for 4,6 or 8 digits. For this design I wanted to see what I could make just using parts available from SparkFun. Get back to basics so to speak.