Piezo motor driver#
Piezo motor full#

Linear stepper piezo motors can generate push/pull forces and holding forces of up to 10 N, and the legs can be preloaded to the runner to produce a self-clamping force with high stiffness, even when no voltage is applied.īecause piezo devices produce no magnetic flux, and all parts of the linear stepper piezo motor can be made from non-magnetic materials, they’re well-suited for environments with strong magnetic fields. Travel lengths up to 150 mm can typically be achieved, with maximum speeds up to 15 mm/s. (They can also travel at extremely slow speeds, in the range of a single micron per second, which is a requirement for precision dispensing and measuring applications.) Although the piezo actuators can produce unlimited linear motion, the stroke of a linear stepper piezo motor is limited by the length of the runner. The motion produced with each “step,” or cycle, is only a few microns, but linear stepper piezo motors make thousands of steps per second, so they can generate long stroke lengths at high speeds.

In a linear stepper piezo motor, pairs of piezo actuators work together, like legs, to create a walking motion that advances a longitudinal rod. As this is happening, the next set of legs is extending downward to grip the runner, advance it forward, and then retract. Next, the legs bend sideways, advancing the runner, and then contract to release the runner. When voltage is applied to the piezo motor, one pair of piezo elements (legs) extends downward and grips a longitudinal rod (also referred to as a runner) via friction elements on the ends of the legs.

The four actuators, which can undergo two types of motion - expansion/contraction in length and sideways bending - are activated in pairs, analogous to legs. Linear stepper piezo motors are made up of several (typically four) piezo stack actuators mounted in a row. How do you get a piezo motor to walk? One step at a time. Although their construction and principles of operation are different, all three designs harness the inverse piezoelectric effect - in which a piezo material expands or contracts when electrical energy is applied - to produce linear movement in a longitudinal rod.

Piezo motor driver#

The MAX77501 is available in a 30-bump, 0.4mm pitch, wafer-level package (WLP).ĭesign Solution: Piezo Haptic Driver Extends Portables’ Battery Life ›Piezo motors that produce linear motion include linear ultrasonic piezo motors, linear stepper piezo motors, and piezo inertia motors.

The IC also implements an ultra-low power boost architecture providing the lowest power consumption solution for a haptic actuator driver.īuilt-in undervoltage lockout (UVLO), cycle-by-cycle overcurrent limit, overvoltage and thermal shutdown protections ensure safe operation under abnormal operating conditions. The on-board memory can be dynamically allocated as multiple waveforms storage or as a FIFO buffer. This allows for a rapid 600µs playback start-up time from shutdown.

Piezo motor full#

Memory playback and haptic waveforms real-time streaming modes are supported.Ī 25MHz SPI interface provides full system access and control, including fault reporting and monitoring. It can generate a single-ended haptic waveform of up to 110V PK-PK amplitude from a 2.8V to 5.5V input power supply or a single cell Li+ battery. The MAX77501 is a high-efficiency controller driver for piezo haptic actuators and is optimized for driving up to 2♟ piezo elements.