FanTray: monimod uC doesn't go into full power down even if shutdown with shdn_n line
The reason is that uC still gets power through I/Os. Therefore now we pull i2c lines to "0" when restarting Monimod. However, still it seems that it's getting ~1.4V through I/Os where OPAMPs are connected. When we tested with a fantray where OPAMPs IC7, IC8, IC9 were not soldered, power cycling worked perfectly and voltage on the uC was dropping to 0V.
Even if the power cycle seems to work (all fans stop), in radiation tests, this remaining voltage is not enough to fully power cycle the uC core and it stays stuck until full crate power cycle is performed.