MIKROE MR Angle Click is a compact add-on board that contains a magnetoresistive sensor with an integrated amplifier. This board features the KMZ60, a high precision sensor for magnetic angle measurement with single-ended cosine and sine outputs from NXP Semiconductors. The MR sensor element comes with two Wheatstone bridges for cosine and sine signals, supports functions for control circuit and signal amplification, and enables angular measurements with high accuracy by an excellent linearity and temperature drift behavior. The KMZ60 is fully automotive qualified as well as applicable for industrial and consumer applications. This Click board™ is suitable for rotor position detection for BLDC motors and Electronic Power Steering (EPS) applications, steering angle measurement, window wiper position detection, and general contactless angular measurement (e.g., throttle valves or actuators).
MR Angle Click as its foundation uses the KMZ60, a high precision sensor for magnetic angle measurement from NXP Semiconductors. The integrated MR sensor element, a sensitive magnetic field sensor, employs the MR effect of thin-film permalloy. The sensor contains two parallel supplied Wheatstone bridges, which enclose a sensitive angle of 45 degrees. A rotating magnetic field in the surface parallel to the chip (x-y plane) will deliver two independent sinusoidal output signals, one following a cosine and the second following a sine function. It also comes with a Power-Down mode to enable or disable the device and a possibility for the temperature coefficient of the sensor amplitude to be compensated.
MR Angle Click communicates with MCU through the SPI serial interface using the MCP3204, a 12-bit 4-channel A/D converter from Microchip. The output sine and cosine signals from the KMZ60 are wired as pseudo-differential input signals to the MCP3204. The MCP3204 samples both channels of the sensor simultaneously using an SPI interface, allowing access to both channels on one data line. Besides, it possesses additional functionality routed on two GPIO pins, such as Power-Down mode and temperature compensation.
The KMZ60 can be used as specified with temperature compensation of the MR sensor signal. Pin TCE is used to enable the temperature compensation, routed on the RST pin of the mikroBUS™ socket (connected to the ground if no temperature compensation is required). The output signal amplitude will decrease with increasing temperature related to the temperature compensation of the MR sensor. The Power-Down feature labeled as PDN and routed on the PWM pin of the mikroBUS™ socket switches the device into Power-Down mode and sets the sine and cosine outputs in a high impedance state to avoid current consumption.
This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to properly use the SPI communication lines. 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.
MR Angle Click is supported by a mikroSDK compliant library, which includes functions that simplify software development.
- Interface: SPI
- Compatibility: mikroBUS™
- Dimensions: 42.9 x 25.4mm
- Input Voltage: 3.3V or 5V