This is a first test run of my future clock with only two digits I've made so far. Each segment is made of two 1000mcd LED's in serial pointed against each other, blocks are common anode connected, and CD4511 is used to convert BCD to 7-segment and drive ULN2003A to light the led's. I'm using the A,B,C,D lines as a common bus shared by all 4511's and LE (latch enable) as a sort of parallel addressing driven by the output of 74HC42 BCD-to-decimal converter, which is controlled by only 3 pins of uC, so there are only 7 pins of the uC used :)
Judging from the video, it's a nice, even distribution of light within each segment, but I think you need some "shielding", e.g. in the form of black paper or tin foil, to prevent light from lit segments to leak into adjacent unlit segments.
AssemblerGuy 9 months ago
what happens when you eventually get a dead led?
is there an easy way to replace it?
Inuyasha44320 3 years ago
cool
jaa93997 4 years ago
I'm trying to make a large 4 digit 7 segment display. Would you consider posting a DIY or a HOWTO?
mtomaino76 4 years ago