Center stage with Hall sensors


Have you heard about TI’s family of Hall effect sensors? The first four stars are here: DRV5013, DRV5023, DRV5033 and DRV5053.

We are all curious what star roles these new parts will play. One of the more famous roles of the Hall sensor is to co-star with the BLDC motor as the sensors of the electronic commutator. But the Hall sensor is truly a versatile actor. There are so many other leading roles for the Hall sensor. Some of the casting of these parts into certain designs might be new to you. Join me as we explore some of the stages where the Hall Effect sensor can perform and shine. Where would you cast the Hall sensor?

1. Hall commutation sensor for BLDC motors

This is a classic Hall sensor application. A single latched Hall sensor (ex. DRV5013) is used in single phase BLDC motors and three latch Hall sensors are used in three phase BLDC motors.

 

2. Current sense module and clamps

Linear Hall sensors can provide an accurate, non-contact and sensitive way of current measurement. As shown below, the flux density in the air gap which sensed by the linear Hall sensor is proportion to the current through the coils or the magnet ring. Note that a high resolution and linear type Hall sensor must be needed for accurate current sense applications.


3. Hall travel switch (position sensor)

Hall travel switches are used quite often in industrial machine tools for the mechanical origin or boundary position. The switch type of Hall sensor is used (ie. DRV5023 or DRV5033).

              


4. Displacement detector (displacement sensor)

Anywhere the displacement of a small distance needs to be measured, analog Hall sensors (ex. DRV5053) can be used along with magnets. The following figure shows two types of displacement detection configurations.


5. Handlebar and trigger

Hall sensors can be used in the e-bike, power tool handles and also in the trigger of power tools. Analog type Hall sensors are used in these applications.


6. Game controller

There are two Hall sensors inside each game controller to provide high resolution and long life sensing, which increases the responsiveness, precision and most of the fun of gaming.  These are used to control industrial designs and require an analog type of Hall sensor.

7. Joystick

Similarly to certain controllers, joysticks or control columns are widely used in industrial environments. They require a long life and high accuracy and must be immune to water and dust, making the Hall sensor a perfect non-contact angle detection device. The figure below on the right shows a cool Hall sensor-based flight training stick.

                

 

8. Smart cover for tablets and phones

How does a phone or tablet cover wake up or put your mobile device to sleep? Yes, a magnet placed in the cover and a switch type Hall sensor placed under the screen makes it happen. The Hall sensor is everywhere.

 

9. Bike torque control

Some e-bikes provide constant torque control. That is thanks to the linear Hall sensor placed in the wheel shaft which can sense the tiny torsion deformation when load torque is presented.


10. Automotive transmission

There are many Hall sensors inside the car transmission box to detect the gear positions. How many Hall sensors are in the last motor any of you designed? Let us know.

11. Hall WAH pedal or expression pedal

If you play electric guitar, you must know this. Potentiometers are used in traditional pedals. But, now many use an analog Hall sensor or infrared light for the angular measurement of the pedal.

                          


12. Foot control of a sewing machine

There is a foot pedal to control the sewing machine spindle speed. An analog Hall sensor is placed inside the controller box to sense the pedal angular position with the help of connecting rods.

13. Liquid level sensor

How does that indicator light come on to tell you to fill up your gas tank? This illustration shows how your tank knows it is full or empty. Of course, the analog Hall sensor could be there.

14. Securities for doors, windows or boxes

Hall switches can be used in doors, windows and boxes to indicate if it is closed or open. The sensor can be placed at a hidden corner with no contact in between.  This is important in home security; Hall sensors keep us safe.

 

15. Gear tooth sensor

A magnetized gear can be sensed by Hall sensors to detect the speed of the gear. There are technologies to make a Hall sensor magnetically biased, so that a normal ferric gear can be sensed. Usually the switch type Hall sensor is used.

There are still many other smart Hall sensor applications not listed, which allow creativity and boundless possibilities.  So, let us start casting the DRV5000 in our next application design.

  • Its amazing!!. I mean, i studing electric engineer but some things the teachers dont say to you. I cant belive how much the Hall sensor's can do  in the industry , home, and in our cars.

  • Some comments from my viewpoint at an automation system integrator:

    CH Products' industrial hall effect joysticks are sweet, an absolute wonder, etc, and start at ~$100.  They also make nice resistive (potentiometer) joysticks, but the hall effect ones are much nicer (I own 2 hall effect, and 5-6 potentiometer ones).  At least the ones I have use Melexis hall effect chips, but I think the key is the mechanical quality (still made in USA I believe).

    APEM's IH line of industrial switches use hall effect sensing; the IHL models feature a linear 0.5->4.5V output over 4 mm of travel -- that's a unique but pricey (~$60 last time I checked) switch.  BTW, APEM now owns CH Products.

    It seems to me that some of these applications could also be done with TI's new inductive sensing chip.

  • Thanks a lot.!! Securities for doors, windows or boxes topic is TOO GOOD. :)