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Q: TLC5941 - TEST pin by 1754684
customer is replacing the TLC5946 with TLC5941 in his applications: the main difference I noted was the TEST Vs XHALF...
because we want to save the PCB, the TEST pin would be driven by a MCU (since it was in the previous version - XHALF of TLC5941)...
the question is: at the power on, when MCU is still not driving the TEST pin "high" could be there some issue during this little time in which TEST is "low" (for the TLC5946??
many thanks in advance
Vincenzo
A: Re: TLC5941 - TEST pin by 10449
The TLC5941 TEST pin must be actively pulled to a logic H during normal operation. It is ok for the TEST pin to be low during startup as long as it is pulled high before the microprocessor programs the TLC5941. The datasheet states that TEST must be connected to VCC, but it is also acceptable to drive it to a logic H with a microprocessor if you ensure it is a logic H before programming the TLC5941.