4 Conclusions

This application note presented a stepper motor drive solution using the AVR EB family of microcontrollers. The new TCE and WEX peripherals can generate the necessary drive PWMs with internal configurations to reduce code complexity. Microchip provides new hardware supporting the connection and demonstration of a stepper motor, comprising the AVR EB Curiosity Nano, Multi-phase Power Board, and an AVR EB CNANO to MPPB adapter, which can be ordered from the Microchip website.

The application drives the stepper motor in three modes: Full-Step, Half-Step and, Micro-Step, with acceleration and deceleration ramps and dynamic current management. A further use case application has been created to drive two stepper motors sequentially.

Possible enhancements:

Implementing functional safety for stepper motors by constantly measuring voltage, current, and temperature is a proactive approach to ensure the system operates within safe parameters. Functional safety refers to a part of the overall safety that depends on a system or equipment operating correctly in response to its inputs, including the safe management of likely operator errors, hardware failures, and environmental changes.

A method of controlling the acceleration and deceleration of stepper motors to create a smooth motion profile is known as an S-curve acceleration profile, an S-shaped ramp.

To implement an S-shaped ramp, the stepper motor controller needs to be capable of generating the complex motion profile and adjusting the current to the motor coils accordingly, which typically requires more advanced control algorithms and may involve the use of micro-stepping to achieve the desired level of motion smoothness.