Interferential Therapy Unit
Move to microcontroller increases functionality and flexibility
Technologies used


Industrial sector (PRODCOM code)
    331 Electrical Equipment
This report describes the development of a Microcontroller based Interferential Therapy Instrument used in physiotherapy for the treatment of inflammatory conditions and sports injuries. The instrument works by applying two sinusoidal current waveforms directly to the patient through surface electrodes. The project was carried out by SNS Bioengineering Developments Ltd., an English SME with 4 employees, of whom 2 are Electronic Engineers.

The aim was to develop a new product, using a microcontroller, to replace a previous product which used conventional analogue and digital circuitry, simplifying the product design, thereby reducing manufacturing costs and allowing SNS to compete with lower cost imports. Furthermore, the new product is a more flexible device with greater functionality, e.g. automatic detection of remote control when fitted, addition of pre-settable treatment regimes, treatment timer, control of new display. The microcontroller used is a PIC 16C924, an 8-bit device with built in A/D converter and LCD drive circuitry. The software was written in Assembler.

The first user had no previous experience of microcontrollers. The project took 13 months to complete, which was 3 months longer than originally planned. The over-run was caused mainly by late delivery of the LCD, which was manufactured in the Far East. The prototype development cost was 54 K of which the FUSE investment was 26K and industrialisation costs were 7 K. The payback of the FUSE investment is expected to be 3 years and the return on investment, over the 5-year lifetime of the product is estimated to be approximately 600%.

The application experiment will be of interest to companies working in medical electronics, who are considering a move to Microcontroller technology.

SNS Bioengineering Developments Limited
54/56 Lant Street
London SE1 1QP
United Kingdom

Detailed information

You can also benefit from microelectronics

Microcontroller technology provided SNS Bioengineering Developments Limited with the means of improving its products and enhancing its market position. You can also achieve significant benefits by acquiring the right microelectronics technology and utilising it in your product or manufacturing process. You can get help from FUSE to realise this.

FUSE is a technology transfer programme, funded by the European Commission to stimulate the wider use of microelectronics technologies by European enterprises to increase their competitiveness and enhance their economic growth. The demonstrator described here is one of many examples in the public FUSE portfolio covering the whole spectrum of microelectronics technologies and spanning a wide range of applications and industry sectors.

FUSE provides you with:

  • Best practice in acquiring specific microelectronics technologies and conducting full development projects through the FUSE portfolio of real life demonstrator documents.
  • Local training and expert support to plan your innovation realistically and help you conduct your project successfully.

Further information and support relating to this and other demonstrators can be obtained from the addresses below.

Further information   Guiding Technology Transfer Node
For further information and support regarding this case study, please contact a Technology Transfer Node (TTN) in your region.
Homepage: http://www.fuse-network.com
University of Hertfordshire
Erdc, College Lane
AL10 9AB Hatfield
United Kingdom