Hi, I'm running a chain of TLC chips and I can get the FIRST chip to fail with some kind of internal short from VCC to GND pretty consistently. If I replace that chip, everything continues to work.
It seems to me that the only difference between the first chip and the others is that the SIN is coming from the uP. Are there any conditions where SIN is driven by the TLC? I am using SPI to drive the chips, so SIN is being used a lot for other SPI communications. Since the TLC does not have a "chip select" this clocks random data into the TLC all the time, but that does not matter since it is never latched.
How about when the TLC is not powered, etc?
Speaking of which, can the LEDs be powered (i.e. the "OUT" lines) even if the TLC is not powered? What will happen in this situation.
What is the recommended power sequencing?
TI: Please try to reply ASAP (PM me for why)...
Thanks,
Andrew