Bi Hall Click

How does it work?

BI HALL Click is based on the US2882, a bipolar Hall-effect switch designed in mixed signal CMOS technology from Melexis Technologies. The US2882 comes with very high magnetic sensitivity based on mixed-signal CMOS technology. The US2882 integrates a voltage regulator, a Hall sensor with a dynamic offset cancellation system, a Schmitt trigger, and an open-drain output driver, all in a single package. It allows using generic magnets, weak magnets, or more significant air gaps, making it suitable for various automotive, consumer, and BLDC motor applications.

The US2882 exhibits bipolar magnetic switching characteristics. Therefore, it operates with both the South and North poles. Typically, the device behaves as a latch with symmetric operating and release switching points, which means magnetic fields with equivalent strength and opposite directions drive the output HIGH and LOW. In this way, it is possible to determine the pole of the magnet using the information that the host MCU receives from the sensor via the INT line of the mikroBUS™ socket. It is also possible to visually identify the magnet's North Pole via an onboard red LED. Removing the magnetic field keeps the output in its previous state, which defines the US2882 as a magnetic memory.

Depending on the magnetic switching points, the US2882 may also behave as a unipolar positive or negative switch, which means the output can be set HIGH and LOW by only using one magnetic pole. In such a case, removing the magnetic field changes the output level. The chopper-stabilized amplifier uses a switched-capacitor technique to suppress the offset generally observed with Hall sensors and amplifiers. The CMOS technology makes this advanced technique possible, resulting in more stable magnetic characteristics.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the LOGIC LEVEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to 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.

Specifications

Pinout diagram

This table shows how the pinout on BI HALL Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	NC
	NC	2	RST	INT	15	INT	Hall Switxh Output
	NC	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	NC	5	MISO	SCL	12	NC
	NC	6	MOSI	SDA	11	NC
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

BI Hall Click electrical specifications

Software Support

We provide a library for the BI HALL Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for BI HALL Click driver.

Key functions

• Detecting south & north pole magnetic fields status function.

Example Description

Detect the south & north pole magnetic fields.

 void application_task ( void ) 
 { 
     bihall_state = bihall_det_mag_field( &bihall ); 

     if ( ( bihall_state == BIHALL_MAG_POLE_SOUTH ) && ( bihall_state_old == BIHALL_MAG_POLE_NORTH ) ) 
     { 
         bihall_state_old = BIHALL_MAG_POLE_SOUTH; 
         log_printf(&logger, "         ~ SOUTH ~rn"); 
         log_printf(&logger, "--------------------------rn"); 
     } 

     if ( ( bihall_state == BIHALL_MAG_POLE_NORTH ) && ( bihall_state_old == BIHALL_MAG_POLE_SOUTH ) ) 
     { 
         log_printf(&logger, "         ~ NORTH ~rn"); 
         log_printf(&logger, "--------------------------rn"); 
         bihall_state_old = BIHALL_MAG_POLE_NORTH; 
     } 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.BiHall

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.

mikroSDK

This Click board™ is supported with mikroSDK - MikroElektronika Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.