AN3181 Datasheet, PDF (10/31 Pages) STMicroelectronics – Guidelines for obtaining IEC 60335 Class B certification in an STM8 application

Compliance with IEC and VDE standards
AN3181
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
ADC/DAC
Analog components depend on device’s application and peripheral capabilities. Used pins
should be checked at correct intervals. Free analog pins can be used for checking user
analog reference points. Internal references should be checked, too.
I/Os
Class B tests must detect any malfunction on digital I/Os. This could be covered by
plausibility checks together with some other application parts (e.g. change in an analog
signal from temperature sensor when heating/cooling digital control is switched on/off).
Interrupts and external communication
Application interrupts occurrence and external communications can be checked by different
methods. One of them could be a control using a set of incremental counters where every
interrupt or communication event increments a specific counter. The values in the counters
are then verified at given time intervals by cross-checking against some other independent
time base.
Timing
Timing could be verified by ensuring that the application routines execution times are correct
and that there are no unexpected delays. A cross-check with a different time base could be
done. Timing control is strictly dependent on the application.
External addressing
External addressing is not used with STM8 microcontrollers.
10/31
Doc ID 17286 Rev 2