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23 the vendor, third-party tools, and available software modules are factors in making a specic selection, in addition to the hardware functions of the IC itself. Note that these controllers are generally not the same as motor drivers, which are the MOSFET/IGBT drivers/devices that control motor power, for two reasons. First, these power devices must be sized to the motor, independent of the controller. Second, the high-density complementary metal-oxide-semiconductor- based process technologies used for these digital controllers are very different than the processes for power devices. For smaller motors, however, it is possible to integrate the controller with the driver and power device. Despite the fundamental differences, the term "controller" often refers to the power-device functional blocks, which can lead to confusion in keyword searches. Some examples of motion control ICs show the spectrum that these devices span. STMicroelectronics Low-Voltage STSPIN stepper motor drivers integrate in a small QFN 3x3 package both the control logic and a high-efciency power stage (Figure 9). The integrated controller implements PWM current control with xed OFF time and a microstepping resolution up to 1/256th of a step. These devices offer a complete set of protection features including overcurrent, over temperature and short-circuit protection and are optimized for battery power applications. One of the issues with stepper motors, even when used in micro stepping mode, is that their output motion can vibrate as they start or stop their step motion. While not a problem in many situations, it can be a concern in the handling of delicate objects like glassware, or if it induces system resonances. Therefore, the STSPIN motor drivers allows the user to tailor the rise/fall (slow decay + fast decay) of the current drive and establish rise and fall transitions for this current to minimize vibration (Figure 10). At the top end of the motion-control pyramid are advanced units such as those in the STSPIN32F0, (Figure 11), which combines a 32-bit ARM ® Cortex ®-M0 core STM32F0 microcontroller and a three-phase, half-bridge gate driver in a tiny 7x7mm QFN package. The STSPIN32F0 delivers the exibility and power of a microcontroller-based drive with the convenience, simplicity and space-efciency of a single IC. Key features and benets this motor control solution from STMicroelectronics offers include on-chip operational ampliers and comparator to support a wide variety of motors and algorithms bring exibility and scalability to the applications. Also included are on-chip generated power supplies for the MCU and external circuitry. The STSPIN32F0 also benets from an extensive development ecosystem including the STEVAL-SPIN3201 board, software tools, rmware libraries and middleware on top of the popular motion-control algorithms such as Field-Oriented Control (FOC) and 6-step control to streamline rmware development. Additional capabilities of the STPINE32F0 also include types and number of input/output, and housekeeping functions like timers, comparator, and thermal protection. Target applications of the STSPIN32F0 include 3-phase motors, power tools, fans, and small white goods as well as some high- end applications like robotics, 3D printers and drones. Figure 9: The STSPIN220 is a stepper motor driver integrating a microstepping sequencer (up to 1/256th of a step), two PWM current controllers and a power stage composed of two fully-protected full- bridges. (Source: STMicroelectronics) Figure 10: In application, the STMicroelectronics STSPIN220 implements two independent PWM current controllers, one for each full bridge. The decay sequence starts turning on both the low sides of the full bridge. When 5/8ths of the programmed OFF time (tOFF,SLOW) has expired, the decay sequence performs a quasisynchronous fast decay leading to optimal micro-stepping current regulation. (Source: STMicroelectronics)

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