UNI HALL Click

How does it work?

UNI HALL Click is based on the US5881, a unipolar Hall-effect switch designed in mixed signal CMOS technology from Melexis Technologies. The US5881 comes with very low magnetic sensitivity based on mixed-signal CMOS technology. It 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. Its sensitivity enables high accuracy in position sensing by using a small air gap, making it suitable for various automotive, consumer, and industrial applications.

The US5881 exhibits unipolar magnetic switching characteristics. Therefore, it operates only with one magnetic pole – North. Applying a North magnetic pole greater than a magnetic operating point of 25mT, facing the branded side of the package, switches the output of the US5881 to a LOW logic state. 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 switches the output HIGH. The opposite magnetic pole facing the branded side does not affect the output state.

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 UNI 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 Switch 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

UNI HALL Click electrical specifications

Software Support

We provide a library for the UNI 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 UNI HALL Click driver.

Key functions

• Detecting north pole magnetic fields status function.

Example Description

This is a example which demonstrates the use of UNI HALL Click board.

 void application_task ( void ) 
 { 
     unihall_state = unihall_detecting_magnetic_fields( &unihall ); 

     if ( ( unihall_state == UNIHALL_NORTH_POLE_NOT_DETECTED ) && ( unihall_state_old == UNIHALL_NORTH_POLE_DETECTED ) ) 
     { 
         unihall_state_old = UNIHALL_NORTH_POLE_NOT_DETECTED; 
         log_printf(&logger, "      ~ NOT DETECTED ~rn"); 
     } 

     if ( ( unihall_state == UNIHALL_NORTH_POLE_DETECTED ) && ( unihall_state_old == UNIHALL_NORTH_POLE_NOT_DETECTED ) ) 
     { 

         log_printf(&logger, "        ~ DETECTED ~rn"); 
         unihall_state_old = UNIHALL_NORTH_POLE_DETECTED; 
     } 
 }

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.UniHall

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.