A6850

The Allegro® A6850 is designed to interface between a microprocessor and a pair of 2-wire Hall effect sensors.

The A6850 uses protected high-side low resistance DMOSMOSFETs to switch the supply voltage to the two Hall effect devices. Each switch can be controlled independently via individual ENABLE pins and both switches are protected with current-limiting circuitry. The output switches are rated to operate to 26.5 V and will source at least 25 mA per channel before current limiting.

Typical two-wire Hall sensor applications of A6850 require the user to measure the supply current to determine whether the Hall sensor is switched on (magnetic field present) or switched off (no magnetic field present). This is usually accomplished by using an external series shunt resistor and protection circuits for the microprocessor. In many systems, the sensed voltage is used as the input to a microprocessor analog-to-digital (A-to-D) input. This provides the system with an indication of the status of the two-wire switch as well as provides the capability for diagnostic information if there is an open or shorted sensor.