HOW DOES IT WORK?

Brushless 15 Click as its foundation uses the TB9061AFNG, an automotive pre-driver that incorporates a sensorless controller for driving a 3-phase full-wave brushless DC motor from Toshiba Semiconductor. A 3-phase motor is driven by the PWM output signals, with the duty cycle determined by the PWM signal from mikroBUS. This input PWM signal is measured, calculated, and corrected in the logic circuit. The TB9061AFNG generates a 20kHz internal PWM signal according to its result. After that, the TB9061AFNG inputs internal PWM into the Sensorless Core Logic and outputs a sensorless driving signal for a 3-phase brushless motor.

In addition to the PWM signal, the internal PWM duty cycle can also be controlled using an analog voltage applied to the ASIG pin of the TB9061AFNG, set manually using an onboard trimmer labeled as VR1. Analog voltage from the VR1 controls the internal PWM duty cycle when the PWM pin is shorted to the ground. The user can also select a forced commutation frequency by choosing the input voltage via an onboard rotary switch labeled as SW1. Using an SW1, the TB9061AFNG receives the voltage at the SFCF (forced commutation frequency select) pin through the internal ADC and decides the forced commutation frequency from 9.375 up to 25.000rpm.

The user can also set a lead angle value at 7.5, 15, or 30° according to the setting of the SW2 switch. When SW2 is in a lower position, a lead angle is set to 7.5°, the upper position represents a lead angle of 15° set, and the middle position matches a lead angle of 30°. If 7.5 or 15° is selected, the lead angle is set to 0° during the forced commutation. When the normal commutation is started, it is changed automatically to the value specified by the SW2. If 30° is selected, the lead angle is set to 30 ° even during the forced commutation.

The TB9061AFNG features several diagnostic circuits and drive control functions, including over-current detection and a motor drive current limiter circuit, over-temperature (both internal and external), and over-voltage detection. Motor lock detection, step-out detection, and automatic return control circuits are also incorporated.

Alongside the PWM pin from the mikroBUS™ socket, used to drive a 3-phase motor, this Click board™ also has the Enable pin labeled as EN and routed to the CS pin of the mikroBUS™ socket to optimize power consumption used for power ON/OFF purposes (performs Start and Stop controls of the motor operation). The DIR pin, routed on the RST pin of the mikroBUS™ socket, is used to select the direction of motor rotation (clockwise/counterclockwise). Besides, it is possible to detect a rotation speed and irregular operations, such as motor lock-up, where the indication of such a condition is performed using the blue LED indicator labeled as OUTFG routed on the INT pin of the mikroBUS™ socket.

This Click board™ supports an external power supply for the motor, which can be connected to the input terminal labeled as VM and should be within the range of 6V to 18V, while the BLDC motor coils can be connected to the terminals labeled as U, V, and W.

This Click board™ can be operated only with a 5V logic voltage level. Therefore, the board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.