6.4

FAULT indication

The FAULT pin is an active low open drain output indicating fault conditions. This pin is activated when at least

one of the following conditions occurs:

•

Junction over-temperature (TJX >TJSD) of one or more channels of the Process Stage or case shut-down

protection (TC >TCSD) is active

•

Internal communication error.

The communication error is intended as an internal data corruption event in the data transfer through isolation. In

case of communication error, the outputs are initially kept in the previous status and then reset (turned off) at the

first communication error during data transfer of the refresh signal

6.4.1

Junction overtemperature

The thermal status of the device is updated during each transmission sequence between the two isolated stages.

In SCM operation, when LOAD signal is high and SYNC one is low, the communication between the two stages

is disabled. In this case the thermal status of the device cannot be updated, and the FAULT indication could be

different to the actual status. In any case, the thermal protections of the channel outputs in the Process Stage are

always operative.

Figure 15. Thermal status update

ISO808, ISO808-1

FAULT

indication

DS14169 - Rev 1

page 20/38