By using microcontrollers (MCUs) wisely, design engineers can cut costs and reduce complexity of mechatronic systems. Unfortunately, they often overlook the onboard capabilities of their MCUs, and end up spending more money than is necessary.
Keith Curtis, technical staff engineer for Microchip Technology Inc. , told an audience of Design News Radio listeners that it's easy for mechatronic systems designers to reach for the obvious components -- such as sensors and converters -- even when they may not be needed. The result can be a product that is too complex and costly.
In a wide-ranging half-hour discussion, "Microcontrollers for Mechatronics," Curtis addressed questions about the future of mechatronic control.
"They build it up and find out their not hitting their price point," he said during the
broadcast. "But if you look at what's in the microcontroller, and look at other ways it can be used, there is a way to shave cost out of the design."
Microcontrollers often have capabilities, such as capacitive sensing, that can be used instead of external sensors, Curtis said. He cited an example of a mechatronic system that needs to measure angular velocity. Many designers would employ dedicated sensors to monitor those parameters, and then would need to employ dedicated analog-to-digital (A/D) converters to work with those sensors.
"Everyone says, 'I need a rotary encoder, and then I've got to have an A/D converter to read it,' " he said. "But a lot of MCUs are now coming out with capacitive touch interfaces, so I can do the conversion with the 'cap sense' input. Now I've got a cheap sensor, and (the signal) never goes to analog, and I'm using a built-in peripheral in the micro that was already there."
The same could be said for current control of a motor. Microcontrollers with pulse width modulation capabilities can often eliminate the need for separate sensors to help with current control feedback on motor drives, Curtis said.