Full die redundancy programmable linear Hall sensor IC

January 03, 2017 // By Julien Happich
The A1346 from Allegro MicroSystems Europe is a dual-die, highly programmable linear Hall sensor IC that aimed at safety-critical applications. The chip incorporates full die redundancy with the added benefits of full diagnostics.

The combination of these two features allow for a higher level of diagnostics without interruption to the application (where diagnostics would otherwise render a die temporarily unresponsive), and also allows the controller to know which die to trust when the two outputs do not agree. The new device incorporates dual high-precision, programmable Hall-effect linear sensor integrated circuits with open-drain outputs, for both automotive and nonautomotive applications. The signal paths in the A1346 provide flexibility through external programming that allows the generation of accurate and customised outputs from an input magnetic signal.

Each BiCMOS monolithic integrated circuit incorporates a system-on-chip configuration that includes a Hall sensing element, precision temperature compensating circuitry to reduce the intrinsic sensitivity and offset drift of the Hall element, a small-signal high-gain amplifier, proprietary dynamic offset cancellation circuits, advanced output linearisation circuitry, and advanced diagnostic detection.

A key feature of the A1346 is its ability to produce a highly linear device output for nonlinear input magnetic fields. To achieve this, it features 16-segment customer programmable linearisation, where a unique linearisation coefficient factor is applied to each segment. Linearisation coefficients are stored in a lookup table in EEPROM.