Product Roundup – Hall-Effect Sensors

When used as an electronic switch, Hall effect sensors provide a dramatic savings and greater reliability compared to mechanical switches. Hall effect sensors are not affected by environmental contaminants as they are housed in a sealed package and can withstand severe conditions. Hall effect sensors can also be operated up to 100 kHz and—since a solid-state switch with hysteresis is used rather than a mechanical contact—there is no contact bounce.  


Figure 1: Hall effect sensor principals. (Source: Electronics Tutorials)

One common position sensing application utilizes Hall effect sensors to determine if flip covers are closed on smartphones. In DC current transformers, they are also used for contactless calculations of DC current in the conductor. In addition, these sensors are used in such automotive applications as fuel-level indicators to indicate the position of a floating element. In this application, a current carrying conductor is fixed on the top of the tank lining up with the magnet so that when fuel levels rise, an increasing magnetic field is applied on the current yielding a higher Hall voltage. When fuel levels decrease, so does the Hall voltage.

Honeywell’s SS496B-SP Hall effect sensor is designed for use in liquid-level sensing as well as vibration and weight sensing, current and position sensing, motor control, magnetic code reading, ferrous metal detection and as a rotary encoder. Integrated circuitry increases temperature stability and sensitivity and laser-trimmed thin-film resistors on the chip provide high accuracy and temperature compensation. The positive temperature coefficient of the sensitivity (+0.02 % °C typical) compensates for the negative temperature coefficients of low-cost magnets.

The Texas Instruments DRV5023BIQDBZT Hall effect sensor is designed for docking detection, door open and close detection, proximity sensing, valve positioning and pulse counting. The device is a chopper-stabilized Hall effect sensor offering magnetic sensing plus superior sensitivity over temperature and integrated protection. Wide operating voltage from 2.5 V to 38 V and reverse-polarity protection to -22 V, yields a device suitable for a myriad of industrial apps.

In comparison, Honeywell’s HRS100SSAB090 Hall effect sensor is designed for automotive, marine, forklift, industrial truck and farm equipment, as well as medical instrumentation. The HRS100 Hall effect rotary position sensor provides angular position information and magnetically coupled information in place of a mechanical wiper assembly. Thus, it provides a cost-effective solution for a long live in harsh environments, including temperature, vibration, dither, moisture and dirt when compared with previous solutions.

Littelfuse’s 55100-3M-03-A mini flange-mount Hall effect sensor features magnetically operated position sensing with digital, latching or programmable analog types available. There offer medium, high or programmable sensitivities and 3-wire or 2-wire output versions. Reverse and over-voltage protection is provided, as is built-in temperature compensation. Applications include position and limit sensing, RPM measurement, flow metering, commutation of brushless DC motors, angle sensing and magnetic encoders.