Magnetic sensor ICs maximise battery life

Allegro MicroSystems Europe has announced the release of a family of Micropower Hall-effect switch ICs. The APS11700 and APS11760 are designed specifically for battery powered applications in harsh industrial and automotive environments. Automatic power management enables average supply current as low six microA while operating directly from a vehicle battery or other unregulated supply. The power management happens in the background and is transparent to the host system, making them a drop-in upgrade for existing Hall-effect switches or a solid-state replacement for mechanical microswitches or reed switches, says Allegro.

These monolithic devices include either a standard Hall plate or a vertical Hall plate, a small-signal amplifier, chopper stabilisation, a Schmitt trigger, automatic power management controller, and an NMOS output transistor. The APS11700 uses a standard planar Hall-effect sensing element, and the APS11760 implements AVHT technology in the form of a silicon-based vertical Hall-effect sensing element. The APS11760 devices are sensitive to magnetic flux parallel to the face of the IC package, mimicking the in-plane sensitivity of common reed switches.

The APS11700/760 devices come pre-configured with the user’s choice of magnetic sensitivity, thresholds, and polarity. There is also a choice of active-high or active-low output for ease of integration into electronic subsystems. These ICs are qualified to AEC-Q100 Grade 0 and comply to ISO 26262:2011 ASIL A when properly applied, making them suitable for automotive and other safety systems.

The ICs can tolerate up to 40V and junction temperature up to 165 degrees C.  In addition, they are internally protected against over-voltage, reverse-battery, load-dump, output short-circuits, human-body-model ESD up to ±11kV, and other EMC conditions.

Typical applications include open/close/latch sensors for automotive doors, lids, trunks, LCD screens, interior lighting. They can also be used for gear sticks, pedals, and other driver controls and human machine interfaces (HMIs), fluid level sensing, tip-over (bank angle), kickstand, and HMI sensors in two- and three-wheeled vehicles, white goods and appliances, intelligent motion, e.g. robotics, vending machines, exercise equipment, motorised blinds/shades/shutters.

Two package styles are available; Allegro’s LH package is a SOT-23W style, miniature, low-profile package for surface-mount applications; the UA is a 3-pin, ultra-mini, single inline package (SIP) for through-hole mounting. Both packages are lead (Pb) free, with 100% matt-tin leadframe plating.

http://www.allegromicro.com