GMR Angle Click

How does it work?

The GMR Angle click contains the TLI5012B E1000 from  Infineon Technologies AG, GMR-based is a 360° angle sensor, for detects any kind the orientation of a magnetic field, and the analog multiplexer 74HCT4053, switch a bi-directional Synchronous Serial Communication DATA line. This is achieved by measuring sine and cosine angle components with monolithic integrated Giant Magneto Resistance (iGMR) elements. These raw signals (sine and cosine) are digitally processed internally to calculate the angle orientation of the magnetic field (magnet).

The calibration parameters are stored in laser fuses. At start-up the values of the fuses are written into flip-flops, where these values can be changed by the application-specific parameters. Further precision of the angle measurement over a wide temperature range and a long lifetime are improved with the internal autocalibration algorithm.

The Giant Magneto Resistance (GMR) sensor is implemented using vertical integration. This means that the GMR-sensitive areas are integrated above the logic part of the TLI5012B E1000 device. These GMR elements change their resistance depending on the direction of the magnetic field. Four individual GMR elements are connected to one Wheatstone sensor bridge. These GMR elements sense one of two components of the applied magnetic field: • X component, Vx (cosine) or the • Y component, Vy (sine) With this full-bridge structure the maximum GMR signal is available and temperature effects cancel out each other

The GMR Angle click also features the 74HCT4053, which is a triple single-pole double-throw analog switch (3x SPDT) suitable for use in analog or digital 2:1 multiplexer/demultiplexer applications. Each switch features a digital select input (Sn), two independent inputs/outputs (nY0 and nY1) and a common input/output (nZ). A digital enable input (E) is common to all switches. When E is HIGH, the switches are turned off. Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of VCC. When CSS pin on microBUS is HIGH, switches in multiplexer connect DATA line with MOSI line, in other case when CSS pin is LOW, swithces connect DATA line with MISO line.

The 74HCT4053 is mainly used for Analog multiplexing and demultiplexing, Digital multiplexing and demultiplexing and Signal gating, but in this one the 74HCT4053 is used for selection SPI line.

These feature enable the GMR Angle click to be used for various applications, most notably for angular position sensing in industrial and consumer applications such as electrical commutated motor (e.g. BLDC), fans or pumps.

Specifications

Pinout diagram

This table shows how the pinout on GMR Angle click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
Interface A	IFA	1	AN	PWM	16	IFC	Interface C
Communication serial select	CSS	2	RST	INT	15	IFB	Interface B
SPI Chip Enable	CS	3	CS	RX	14	NC
SPI Clock	SCK	4	SCK	TX	13	NC
SPI SDO	SDO	5	MISO	SCL	12	NC
SPI SDI	SDI	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

Software Support

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

Library Description

The library covers all the necessary functions to control GMR Angle click board. A library performs a standard SPI interface communication.

Key functions:

• uint16_t gmrangle_readData( uint8_t registerAddress ) – Generic read 16-bit data function.
• void gmrangle_writeData( uint8_t registerAddress, uint16_t writeData ) – Generic write 16-bit data function.
• float gmrangle_calculateAngle() – Calculate angle function.

Examples description

The application is composed of three sections :

• System Initialization – Initializes SPI, GPIO and LOG structures, sets AN and INT pins as input and RST, CS and PWM pins as output and start to write log.
• Application Initialization – Initialization driver enables – SPI, initializes, also write log.
• Application Task – (code snippet) This is an example which demonstrates the use of GMR Angle Click board. Display angle value in degrees. Results are being sent to the Usart Terminal where you can track their changes. All data logs write on USB uart changes for every 1 sec.

void applicationTask()
{
    angle = gmrangle_calculateAngle();

    FloatToStr( angle, logText );
    mikrobus_logWrite( " Angle is ", _LOG_TEXT );
    mikrobus_logWrite( logText, _LOG_TEXT );
    mikrobus_logWrite( degCel, _LOG_LINE );
    mikrobus_logWrite( "---------------------", _LOG_LINE );

    Delay_1sec();
}

The full application code, and ready to use projects can be found on our LibStock page.

Other mikroE Libraries used in the example:

• SPI
• UART
• Conversions

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. The terminal available in all MikroElektronika compilers, or any other terminal application of your choice, can be used to read the message.

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.