What is Class B?
IEC60730 Annex H Standard
IEC60730 Annex H Standard documents the requirements for electronic controls. It contains detailed tests and diagnostic methods to ensure the safe operation of embedded control hardware and software for household appliances.
IEC60730 Annex H has 3 software classifications for automatic electronic
Class A - Not intended to be relied upon for the safety of the equipment.
humidity controls, lighting controls, timers.
Class B - Intended to prevent unsafe operation of the controlled equipment.
Examples: thermal cut-offs and door locks for laundry equipment.
Class C - Intended to prevent special hazards, like explosion of the controlled
Example: automatic burner controls, gas fired controlled dryer.
For Microcontrollers, the IEC60730 Annex H explains the detail of the tests and
diagnostic methods to ensure safe operation of embedded control hardware and software for household
Why Class B?
From Oct 2007, home appliances to be sold in Europe have to comply with IEC60730 standard. Class B applies for the majority of home appliances, e.g. cookers, dishwashers, refrigerators, dryers, cloth washers, fans…
How does Infineon support Class B?
For its XMC and XC800 families Infineon is providing Software Library routines,
which can be used for microcontroller internal supervisory functions and for self-diagnostics.
Furthermore this Software Library routines fulfill the requirements according to the Class B standard and were approved by VDE (reference number 5007865-9999-0001/112626).
What is the customer benefit?
The safety features of the microcontrollers offer significant competitive
advantages. In particular, the embedded flash module with its hardware error correction (ECC), and
the invariable memory tests which are done without the need to implement the time consuming
CRC-memory checker routines. The ECC can correct single bit error and can inherently signal such
events to the application with every flash access. This increases CPU performance, frees-up memory
space and makes user software easier and safer.
The microcontrollers come with a sophisticated clock supervisory feature. The clock control with it’s on-chip oscillator and PLL, can detect clock faults such as the loss of lock, or double and half frequency. If clock failure occurs, the system is automatically brought into a safe-state and a signal is sent to the event application.
The features described make an application safer without additional cost and overhead.
How to implement?
A dedicated Software Library provides self test routines which the user can call
at system startup or periodically at system run time.
A quick start step by step testing guide on Software Library will be provided to the user.
Download Class B Library