Drive a bipolar stepping motor easily with TB67S549FTG and PIC18F57Q43

Stepper 12 Click is based on the TB67S549FTG, a two-phase bipolar stepping motor driver designed to control one bipolar stepping motor with resistorless current sensing owing to the built-in function of Advanced Current Detect System (ACDS) from Toshiba Semiconductor. The TB67S549FTG incorporates low on-resistance DMOS FETs, which can deliver a 1.5A maximum current with a motor output voltage rating of 40V and integrated protection mechanisms such as over-current, over-temperature, and under-voltage lockout for error detection (LO LED indicator). It supports full-step to 1/32 steps resolution for less motor noise and smoother control, with a built-in Advanced Dynamic Mixed Decay (ADMD) function that helps stabilize the current waveforms. Thanks to the many steps that TB67S549FTG supports, motor noise can be significantly reduced with smoother operation and more precise control. It is suited to various applications such as office automation and commercial and industrial equipment. The current value in the PWM constant-current mode is set by the reference voltage obtained by the MCP1501, a high-precision voltage regulator. Also, the current threshold point of the TB67S549FTG, alongside MCP1501, can be set manually using an onboard trimmer labeled VR.

In addition to the I2C communication, several GPIO pins connected to the mikroBUS™ socket pins are also used to forward the information to the MCU associated with the PCA9555A port expander. The PCA9555A also allows choosing the least significant bit (LSB) of its I2C slave address by positioning SMD jumpers labeled as ADDR SEL to an appropriate position marked as 0 and 1, alongside its interrupt feature routed to the INT pin of the mikroBUS™ socket. The CLK clock signal, routed to the PWM pin of the mikroBUS™ socket, shifts the current step and electrical angle of the motor with its every up-edge, while the Enable pin, labeled as EN and routed to the CS pin of the mikroBUS™ socket, controls the state of the output A and B stepping motor drive channels. The normal constant current control is started by turning the motor drive ON (HIGH level), while by setting the motor drive OFF, the outputs are turned high impedance because the MOSFETs are set to OFF (LOW level). Besides, all circuits can be stopped using the Sleep function and thus enable power saving mode. A simple DIR pin routed to the AN pin on the mikroBUS™ socket allows MCU to manage the direction of the stepper motor (clockwise or counterclockwise), while the RST pin of the mikroBUS™ socket

initializes an electrical angle in the internal counter to set an initial position. Achieving an initial position is indicated via onboard orange LED labeled as MO. A specific addition to this Click board™ is a multifunctional switch that allows the user, by selecting a particular switch, to set appropriate features such as 1 – Sleep Mode Activation; 2, 3 – Motor Torque Setting; 5 – Decay Control; 6, 7, 8 – Step Resolution Setting. In addition to this physical way of setting these functions, the user can select them digitally via the I2C interface. The Stepper 12 Click supports an external power supply for the TB67S549FTG, which can be connected to the input terminal labeled as VM and should be within the range of 4.5V to 34V, while the stepper motor coils can be connected to the terminals labeled as B+, B-, A-, and A+. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

PIC18F57Q43 Curiosity Nano evaluation kit is a cutting-edge hardware platform designed to evaluate microcontrollers within the PIC18-Q43 family. Central to its design is the inclusion of the powerful PIC18F57Q43 microcontroller (MCU), offering advanced functionalities and robust performance. Key features of this evaluation kit include a yellow user LED and a responsive

mechanical user switch, providing seamless interaction and testing. The provision for a 32.768kHz crystal footprint ensures precision timing capabilities. With an onboard debugger boasting a green power and status LED, programming and debugging become intuitive and efficient. Further enhancing its utility is the Virtual serial port (CDC) and a debug GPIO channel (DGI

GPIO), offering extensive connectivity options. Powered via USB, this kit boasts an adjustable target voltage feature facilitated by the MIC5353 LDO regulator, ensuring stable operation with an output voltage ranging from 1.8V to 5.1V, with a maximum output current of 500mA, subject to ambient temperature and voltage constraints.