The drive to provide more creature comforts and automate tasks is prompting an increase in the number of small motors that move seats, windows, mirrors, and perform other actions. That is prompting silicon makers to roll out a number of products that meet the power requirements of these motors.
While much of the focus on power handling and motors is aimed at electrified powertrains, the small motors used in both hybrids and conventional petroleum-fueled vehicles are expected to see far higher volumes.
“Some market analysts predict that the average car will have 38 motors by 2016, for a total of 3.8 billion motors,” said Bruce Beyer, Chassis and Safety Product Marketing Manager at Freescale Semiconductors.
At the recent 2012 SAE Convergence conference in Detroit, vendors made several moves to address this increase. For example, Freescale unveiled a series of motor control development kits to help engineers get designs to market quickly.
“Engineers are using more electric motors to replace hydraulics and add features,” Beyer said. “When you have more motors, managing them precisely helps you improve fuel efficiency and reduce battery/alternator requirements.”
Other semiconductor makers also unveiled new chips at the conference. Many of the introductions covered different aspects of power and logic.
“We added 12 models to our Hercules microcontroller line, adding pulse width modulation for motor control,” said Dave Maples, Safety MCU Product Line Manager at Texas Instruments. “That will help people move to brushless motors.”
The shift to brushless motors, which are quieter and use less power than brushed motors, is highlighting the role of sensors. For example, NXP Semiconductors is focusing its design efforts on anisotropic magnetoresistive (AMR) sensors that work with any type of magnet, not just those relying on rare earth materials.
That can help reduce costs. Other sensor makers are using different techniques that they feel will bring big benefits.
“Reduction in size/weight to half that of a classic dc motor is possible,” said Thomas Freitag, Marketing Manager, Actuators Business Unit at Melexis. “Noise reduction is by sine wave control.”
As automakers use more of these small motors, they’re trying to give drivers more features. That ranges from smoother seat movement to higher-power motors such as those used in electronic power steering.
“We have sensors that give the position of the motor anchor so you can get more precise positioning for electronic power steering,” said Bernd Gessner, Automotive Business Unit General Manager of AMS, formerly Austriamicrosystems.