Hi,
I have a design with two UCD9248 controllers, where a CPU monitors all voltages, currents and temperaturs by regularly polling the UCD9248 controllers over PMBus. The problem is that the command READ_VIN sometimes fails. When it fails, it is because the UCD9248 clock streches SMBC, violating "Cumulative clock low slave extend time" t(LOW:SEXT). The other commands (PMBUS_READ_VOUT, PMBUS_READ_IOUT, PMBUS_READ_IIN, PMBUS_READ_TEMPERATURE_1 and PMBUS_READ_TEMPERATURE_2) never fails, and READ_VIN only fails sometimes
Best regards,
Lukas