Microchip Technology Inc

Home Appliance

Class-B Safety Software

Modern home appliances have made once tedious tasks simple to accomplish. What once took hours of exertion can now be accomplished with a few presses of a button. Modern appliances are in large part electronically controlled. Electronic controls enable higher efficiencies, additional functionality and an improved user experience. But what happens if something goes wrong? Safety specifications, such as IEC 60335, are used to ensure manufactures have designed their products to operate safely. IEC 60335 defines safety standards at a system level. IEC 60730, which is referenced by IEC 60335, addresses safety of electronic controls in appliances. Currently IEC 60730 is mandatory for appliances sold in Europe and widespread adoption is likely. IEC 60730 Annex H defines safety requirements for electronic controls and acceptable measures to address faults/errors are defined in Table H.1 (H.11.12.7 in edition 3).

Microchip has developed a library of low-level software routines and hardware peripherals that simplify meeting IEC 60730 requirements for Class B Safety. Each product family (PIC16, PIC18, PIC24, dsPIC DSC and PIC32) has functions specifically designed work efficiently with the available resources. Application Note AN1229 describes the Application Programming Interface (API) functions that are available in the Class B Safety Software Library and how to incorporate them in your project.

Microchip ARM Cortex M0+ devices are supported by the free Hitex Class-B Library. Download is available from the Hitex site at the following link: Microchip Hitex ARM Class-B Library.  VDE Certificates are available in the documents tab below.

There are several advantages to using the Class B Safety Software Library. First, it reduces development time. Each function has been optimized and thoroughly tested based on each architecture and available resources. Second, it reduces the time and cost required to certify the end appliance. By providing test certificate to the testing agency the requirements covered by the Class B Safety Software Library do not have to be retested. Finally, Microchip Application Engineers can provide guidance on how to effectively implement software safety.

For more information please email class-b@microchip.com

Getting Started

Key Features

  • CPU register test
  • Program counter test
  • Variable memory test
  • EEPROM/Flash memory test
  • Clock test
Components Covered by the Class B Safety Software Library
MCU Circuit Component Fault/Error
1 CPU Registers Stuck
2 Program Counter Stuck
3 Interrupt handling and execution No interrupts or too many interrupts
4 Clock Frequency Clock failure or incorrect frequency
5 Memory testing (Flash/EEPROM) All single bit faults
6 Memory testing (RAM) DC fault
Tabs / Home Appliance
Software Libraries
VDE Certification
UL Certificates

Software Libraries

Title File SHA-1 Fingerprint
8-bit PIC16 ClassB Ver 3.01 8-bit PIC16 ClassB Ver 3.01.zip Zip 20f3982f98912a2bb4f99584455d3d711556714f
8-bit PIC18 ClassB Ver 3.00 8-bit PIC18 ClassB Ver 3.00.zip Zip c39548819cfb7da086616cfdb8dada8694fc19dd
8-bit PIC16 ClassB Ver1.02* 8-bit PIC16 ClassB Ver1.02.zip Zip 67a60b230bd110939ec4b2ea3591da1431c32bda
8-bit PIC18 ClassB Ver1.7* 8-bit PIC18 ClassB Ver1.7.zip Zip db618e9aafd4ab4c96ae5c11e6681b468e869f5d
16-bit PIC24 dsPIC ClassB V2.40 16-bit PIC24 dsPIC ClassB V2.40.zip Zip b3f2ff9ede7bfe9e817b2539fc5c6388396c451d
32-bit PIC32 ClassB Ver1.0 32-bit PIC32 ClassB Ver1.0.zip Zip 2786afda82fe677af8fe5fd7a8613f4fc93c90e9
AVR XMEGA Class B library AVR1610.zip Zip 4a73344c409af2efd18ab8e78249f31c1f2e0c80

* Note: Updated versions of the 8-bit PIC libraries are available above and are highly recommended for use in any new designs.  Please use Ver 3.01 for PIC16 designs and Ver 3.00 for PIC18 designs. For questions please contact class-b@microchip.com


SHA-1 Fingerprint
MPLAB® X CRC Calculator Test Project
CRC Calculator
CRC Calc 1.1.zip
Class B Safety Software Library for 8-bit PIC16 PIC® MCUs
Class B Safety Software Library for PIC MCUs and dsPIC® DSCs
Using a Hardware or Software CRC with Enhanced Core...
PIC® MCU Safety Features and Certified Class B Library
Class B Hardware Support and Software Libraries for PIC MCUs - Customer Presentation.pptx
AVR1610: Guide to IEC 60730 Class B Compliance with XMEGA doc42008.pdf PDF b2d14c987fe5d1e4c5a9b6ad11302cf31c869a32 

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