Intelligent Triple Stepper Motor Controller With Serial Peripheral Interfaces

The TMC428 is a miniaturized high performance stepper Motor Controller with a low price for high volume automotive and industrial motion control applications as well. Once initialized, the TMC428 controls up to three independent 2-phase stepper motors from each other. The low price makes it attractive also for those applications, where only one or two stepper motors have to be controlled simultaneously. The TMC428 performs all real time critical tasks autonomously. Thus a low cost micro controller is sufficient to perform the tasks of initialization, application specific interfacing, and to specify target positions and velocities. The TMC428 allows on-the-fly alteration of all target parameters. Read-back option for all internal Registers simplifies programming. The TMC428 CAN perform up to 223 steps respectively micro steps fully independent from the micro controller with its internal position Counters The step resolution individually programmable for each stepper motor ranges from full step, half step, up to 6 bit micro stepping (64 micro steps / full step) for precise positioning and noiseless stepper motor rotation. Optionally, the micro step table common for all motors CAN be adapted to motor characteristics to further enhance smooth, low toque ripple application. The TMC428 uses serial Interfaces for Communication with the micro controller and for the stepper motor drivers. The serial Interface for the micro controller uses a fixed length of 32 bits with a simple protocol, directly connecting to SPI TM Interfaces The serial Interface to the stepper Motor Drivers is flexible configurable for different types even from different vendors with up to 64 bit length for the SPI daisy chain. Our own smart power stepper Motor Drivers TMC288 and TMC289 perfectly fit to the TMC428. Without additional hardware, drivers with same serial Interface polarities of chip select and Clock signals may be mixed in a single chain. To mix drivers with different serial Interface polarities, additional inverters (e.g. 74HC04 74HC14 are required. For those driver chips without serial data send back option, the variant of the TMC428 with two additional chip select outputs is proposed. The TMC428 sends data to the driver chain on demand only, which minimizes the Interface traffic and reduces the power consumption. By Unkown