Stepper motor internal structure and working principle

Real-time monitor the running status of the safety and control of the whole system is very

important,TMC428 provide stateful inspection function.Each processor to send packets to TMC428,TMC428 returns the data to the microprocessor.Most of the motor drive circuit with a serial port are provided with different state (not work,work,etc.) and error sign (short circuit,open circuit,the high temperature).Such,TMC428 can at any time to provide the movement parameters and working mode of motor current and status.From the motor driver Daisy chain back to the TMC428 packet is 48 bits long.TMC428 put it in two 24 bit register.In this way,the microprocessor can directly read the information in the register.Combining TMC428 and TMC236 stepper motor drive control system.TMC236

internal integration HVCMOSFET constitute the complete bridge driving circuit,it adopts constant

current chopper drive way to drive the bipolar two-phase stepper electric vehicle motor motor,and has the characteristics of low power consumption,high efficiency.As shown in figure 3 is three TMC236 3 shaft,motor drive and the TMC428 control principle diagram.Using special of step motor motion controller and driver circuit system with peripheral circuit is simple,strong anti-jamming capability and high reliability etc,can reduce the development cost control circuit.The whole system in addition to the power supply only five IC,therefore,small volume,simple control,particularly applicable to 3 axis when step motor driver.Experiment proved that the control of step motor drive high positioning accuracy,plus,deceleration performance is good,at the same time,the start-stop,inversion is also very good performance.

TMC428 is made up of each unit regispumpster and on-chip RAM.Its internal including

two external serial interface,waveform generator and the pulse generator,micro step unit,multi-port

RAM controller and the interrupt controller.TMC428 generally from the microprocessor control

instruction,the microprocessor is through the sending and receiving fixed length packet of TMC428

registers and RAM to read and write operations.TMC428 register and the function of the on-chip RAM is different.Registers are used to store the overall motor configuration parameters and motion

parameters,and on chip RAM to store the drive serial interface configuration and micro step

table.Refers to the drive motor the population parameter TMC236 in Daisy chain configuration.Motion parameters including the current position of the motor,target location,maximum speed,maximum

acceleration,current ratio,waveform generator and generator parameters,and subdivide microstep resolution,etc.On chip RAM including 64 addresses the data space,each address data can be stored 24 bits wide,before a 32-bit address data is to drive Daisy chain configuration of serial communication

data wholesalemotor.blogspot.com

packets,the 32-bit address data for micro step subdivision table.Drive the serial interface is the

communication interface between TMC428 and Daisy chain drive.From TMC428 to drive between the length of the serial data packet is configurable,so as to adapt to the different types and manufacturers of circuit composed of SPI ring structure,the maximum length of data for 64 - bit.After initialization,TMC428 and stepper motor drives the communication between the is done automatically.Different types of drives can be mixed with SPI interface connection with TMC428 constitute a Daisy chain structure.TMC428 with most manufacturers of stepper motor driver circuit compatible.

It can be directly connected with SPI mouth stepper motor drive,also be able to connect additional devices commonly used parallel port driver.Even with a step,direction of input of stepper motor driver can also by TMC428 control.TMC236 stepper motor drive circuit is very simple to connect

into serial Daisy chain structure,using the TMC428 3 axis stepper motor control system can play a

better TMC428 control characteristics.After the initialization,TMC428 can automatically send packets

to each TMC236 Daisy chain,that is to say,the driver serial interface after initialization can work automatically and without the participation of the microprocessor.As long as the position and velocity can be written into the specified register control motor.TMC428 multi-port RAM controller can manage data access sequence.In this way,the microprocessor can read/write registers at any time

and on chip RAM data.Through waveform generator can handle is stored in registers in the motion parameters and calculate the motor speed curve.Pulse generator is calculated according to the waveform generator speed to generate the step pulse.Stepper pulse generating TMC428 drive serial interface will automatically send packets to stepper motor drive Daisy chain to drive the stepper motor.When using microstep control,micro step started processing unit according to the step pulse

produced by the pulse generator,at the same time according to the selection of micro step resolution

steps to produce the whole,half step and micro pulse,and gave the Daisy chain drive by driving a

serial port.