TMR Mix-Sens Click Board™

The TMR Mix-Sens Click Board™ provides three different Coto Technology RedRock™ TMR magnetic sensors that can be operated with supplied magnets and provide instantaneous visual feedback through LED's that indicate sensor output. These sensors utilize tunneling Magnetoresistance (TMR) technology that provides the lowest power consumption and highest magnetic sensitivity of any available magnetic sensor. With the board you will also receive cylindrical magnets for performing out of the box testing. To get started, you'll need to supply 3.3V and 5V to the corresponding pins (see image below).

How Does The TMR Mix-Sens Click Board™Work?

The first sensor on the TMR Mix-Sens Click Board™ a Coto Technology RedRock RR121-1A23-311 is an ominpolar, 9 Gauss operate, 10Hz sensing frequency, push pull output sensor that consumes an average of only 240nA. This sensor is often used for proximity detection or as a means to signal a battery operated device to wake up or power on. The second sensor on this Click board is an RR121-3C63-311 which is a bi-polar, 10 Gauss operate/-10 Gauss release, 500Hz sensing frequency, push pull output sensor that consumes an average of 1.7uA. This sensor is often used for rotation counting. The third sensor on this Click board is an RR111-1DC2-331 which provides a linear voltage output that is proportional to a magnetic field strength between -10 and 10 Gauss with a sensitivity of -20 mv/V/G and 1.5mA average supply current. This sensor is typically used in level or distance sensing applications and can provide a distance resolution of 1mm.

In addition to being able to access the outputs of the three sensors through the mikroBUS and get information to the host MCU, a visual confirmation of the activation and deactivation of each sensor is provided by means of LEDs placed next to each of the sensors on the board. When operating these sensors with the supplied magnets or magnets of your choosing, the LED's associated with each sensor will activate to visually indicate the sensing of a magnetic field. The LED2 for the RR121-1A23-311 lights up when the operate field strength of 9 Gauss is reached and subsequently turns off when the release field strength of 5 Gauss is reached, providing a hysteresis of 4 Gauss. This can demonstrated by moving the North or South pole of magnet towards the sensor in the direction of the arrow. The LED3 for the RR121-3C63-311 lights up when a South pole field with a magnitude of 10 Gauss or greater is sensed and will stay lit until a North pole of 10 Gauss or higher is sensed. This can be demonstrated by bring in a magnet with one polarity and then reversing it. It can also be demonstrated by rotating the supplied ring magnet in the hole adjacent to the sensor.

The semi-circular array of nine LEDs (LED4-LED12) on the top of the board are used for the RR111-1DC2-331 sensor. Please refer to the image above for the LED numbering. These will light to indicate when the sensor sees a North field, a South field or no field, and the magnitude for each polarity. The middle LED (LD8) will light to indicate no magnetic field (voltage output of Vdd/2). An LM3914 is used for indicating strength of linear output of RR111-1DC2-331 sensor. The operation of this sensor can be demonstrated by moving the North of South pole of the magnet towards the sensor in the direction of the magnet. Alternatively, it can be demonstrated by rotating the ring magnet in the hole adjacent to the sensor.

Holes on the TMR Mix-Sens Click Board™ can be used to ease the installation of rotatable magnet holders.

A diagram showing the output response of all three sensors can be seen in the image below:

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout of the TMR Mix-Sens Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

ONBOARD SETTINGS AND INDICATORS