HOW DOES IT WORK?

Speed Sense Click is based on the A17501, a dual output differential speed and direction sensor from Allegro Microsystems. The sensor consists of three Hall elements incorporated in such a way as to create two independent differential channels. The differential signals are used to produce a highly accurate speed output and, if desired, provide information on the direction of rotation. The advanced self-calibration technique with the digital tracking of the signal results in accurate switch points over the air gap, speed, and temperature. The sensor is immune to common external magnetic disturbance and is ideally suited for asynchronous electric motor applications.

When properly back-biased, the sensor is intended for use with ring magnets or ferromagnetic targets. It poses a temperature-compensated amplifier, as well as a full-range ADC. Besides operating on 5V from the mikroBUS™ socket power rail, you can also add an external power supply over the VEXT connector from 4 up to 24V. The selection can be made over the VIN SEL.

Speed Sense Click uses general-purpose IOs to interrupt the host MCU when detecting the magnet on a spinning wheel. The output channel pins are labeled CHA and CHB. There is also an external header with these channels for connecting an external device (relay, LED, and more).

This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this 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