Mixed signal controller for an experimental magnetotherapy device

The article presents the design of a controller for an experimental magnetotherapy device. The controller realizes precise, digital generation of a 3-phase sinusoidal signal with a frequency of 1 Hz to 5 kHz and slowly variable frequency modulation of 1 Hz to 5 Hz, which is a novelty in the field of magnetotherapy. The structure and operation of the analog filter path and the regulation of the amplitude and the DC component are discussed. A fast STM32F334 microcontroller was used to generate the signal, and an ATmega2560 microcontroller was used to operate the user interface with a color touch display. Laboratory and therapeutic tests confirmed proper operation of the controller.