The A1162 is a unipolar Hall-effect switch with an externally enabled diagnostic function and user-programmable switchpoints. On-chip electromagnetic coils are used to implement self-test of the sensor’s entire magnetic and electrical signal chain. It is designed for systems where precise magnet switchpoints and safety and/or reliability are critical. In normal operating mode, the A1162 functions as a standard unipolar Hall-effect switch. The device output transistor turns on (output signal switches low) in the presence of sufficient magnetic field (>BOP max). The output transistor of the A1162 switches off (output signal switches high) when the magnetic field is removed (<BRP min).
When the diagnostic feature is enabled, the output of the A1162 provides a square wave output which confirms the device is properly sensing the internally generated magnetic field. Therefore, use of the A1162 either eliminates the need for redundant sensors in safety-critical applications or increases robustness in safety-critical applications that might otherwise require redundant sensors (drive-by-wire systems, etc.).
This monolithic IC integrates a voltage regulator, Hall voltage generator, small-signal amplifier, chopper stabilization, Schmitt trigger, and short-circuit-protected open-collector output able to sink up to 25 mA. The on-board regulator permits operation with supply voltages of 3.8 to 24 V. It is temperature-stable and stress-resistant, making it especially suited for operation over temperature ranges up to 150ºC (L temperature range). Superior high-temperature performance is made possible through advanced dynamic offset cancellation techniques, which reduce the residual offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress.