For some reason, I'm obsessed by lowering the amount of pins I'm using to run 4 digits 7 segments LED display common anode (or cathode). I came up with the conceptual idea of using a 595 shift register to feed a CD4511 decoder.
The shift register would feed 4 bit (BCD) to the CD4511 - connected to the led display - and four bit to the common anode or cathode to close the circuit. Then I would multiplex something like:
BCD - 4 Cathodes 0001 0001 (writes 1 on digit 1) 0001 0010 (writes 1 on digit 2) 0001 0100 (writes 1 on digit 3) 0001 1000 (writes 1 on digit 4)
This would allow to daisy chain to add displays without increasing the number of pin used.
My first assumption is that there is either a better way to do it or that it does not work but, I'd like to understand how or why,
Thanks for your input,