HI
I'm troubleshooting some RF problems with digital LEDs (single wire DIN DOUT cascade) . The design of the product is lacking much engineering rigour, but its what I have to work with from the client.
The designer has used an opamp to drive several meters of cable with a string of cascaded digital LEDs on, them a total RFI and EMC nightmare
ie a) low speed opamp cant make square waves, so it starts off bad, and b) no shields anywhere, RF gets into it very easily and muds up the edges.
QUESTION : The date bit rate in the datasheet is given as 1.25uS typical. (800kHz)
This is what it is running at. If it ran at 1/10th of that, or 1/100th of that, will the chips still work?- IE are they edge triggered, or is there some asynchronous timing activity internally
SLowing the clock would permit the opamp to make decent looking waveforms. and permit some scope for EMI filtering from 10-200 MHz RF.
I cant just try it, have to go back to the client to get a change. There isnt time budget for me to dick around with the led's myself. Hmm maybe I can program up my AWG to do this...... That might work
-glen