Hello E2E Community,
we are observing the following error on multiple RI-STU-MRD2 modules:
Some modules "hang" after power-on. Outputs OKT, SYNC and STAT are permanently high, board is not "operating".
The error is random and only happens with some boards (10 out of 40) and only sometimes (1-2 out of 20 starts/power on).
It looks like some boards have a problem if wireless sync is enabled by default (pull-up on WLS pin). If disabled (pull-down on WLS) the problem does not occure (so far).
If a board "hangs" pulling WLS to GND does not solve the problem. But reducing supply voltage from 5V down to 3V gets the board going again.
Testsetup is as follows:
Supply DC-DC low drop out linear 5V supply
VSL, VSP with common decoupling capacitor 100nF
/RDEN pull-up
CRDM pull-up
WLS as described above
Kind regards,
Patrick