Smallest motor drivers for battery-powered devices

July 07, 2016 // By Graham Prophet
STMicroelectronics has, it asserts, the smallest full-featured motor drivers available, to simplify design and save space in battery-powered and portable applications, while providing accuracy and smoothness of motion, and extending runtime of battery-powered devices.

The series currently comprises the STSPIN220 stepper-motor driver, STSPIN230 3-phase brushless-motor (BLDC) driver, and STSPIN240 with two complete on-chip MOSFET bridges for driving two brushed DC motors. Another device designed to drive a single brushed DC motor with the current capability extended to 2.6 Arms will go in production during Q3 2016. The power stage of each device features efficient integrated MOSFETs that minimize energy loss and heat dissipation. Despite their tiny size, there is no compromise in performance or function. The STSPIN220 can drive stepper motors with position resolution of 256 microsteps per step, enabling extremely smooth motion and fine positional accuracy.


All devices benefit from comprehensive built-in protection features including over-current, over-temperature, and short-circuit protection. These ensure ruggedness and reliability, even in harsh industrial environments, without additional components thereby further reducing cost and complexity.


ST’s claims for the parts include improved energy efficiency including a zero-power mode with lowest standby power consumption to extend. battery life. Controlling the motors at the heart of devices such as portable medical pumps and drivers, personal wellness devices, portable point-of-sale devices, miniature robots, surveillance equipment, precision tools, and portable printers requires considerable engineering know-how. One of the biggest challenges is to combine logic and power components in a single chip on tight space and power budgets.


ST says it has gathered all of these ingredients together in its single-chip motor drivers that meet the needs of the most demanding portable and wearable applications. The combination of low power consumption, small form factor, and outstanding performance of ST’s new motor drivers is set to contribute to the widespread adoption of battery-powered IoT devices. Measuring 3 x 3mm, these devices are claimed as the smallest single-chip motor drivers available.


The drivers operate from a supply voltage as low as 1.8V and support power-saving design with standby current of less than 80 nA for a zero-power state when the motor is