New linear Hall-effect sensor ICs designed for the automotive and industrial markets

Allegro MicroSystems has two new linear Hall-effect sensor ICs with analogue output, targeted at the automotive and industrial markets. New applications for linear output Hall-effect sensor ICs, such as displacement and angular position, require higher accuracy and smaller package sizes. The company’s A1308 and A1309 devices have been designed specifically to meet both requirements. Target applications include EPS – torque sensing, EPS – angle sensing, and transmission – fork position sensing. These temperature-stable devices are available in both surface-mount and through-hole packages. The accuracy of each device is enhanced via end-of-line optimisation. Each device features nonvolatile memory to optimise device sensitivity and the quiescent voltage output (QVO: output in the absence of a magnetic field) for a given application or circuit. This optimised performance is sustained across the full operating temperature range by programming the temperature coefficient for both sensitivity and QVO at end-of-line test. These ratiometric Hall-effect sensor ICs provide a voltage output that is proportional to the applied magnetic field. The quiescent voltage output is adjusted around 50% of the supply voltage. The features of these linear devices make them ideal for use in automotive and industrial applications requiring high accuracy, and they operate across an extended temperature range, -40C to 150C (SOT-23W) or -40C to 125C (SIP). Each BiCMOS monolithic circuit integrates a Hall element, temperature-compensating circuitry to reduce the intrinsic sensitivity drift of the Hall element, a small-signal high-gain amplifier, a clamped low-impedance output stage, and a proprietary dynamic offset cancellation technique.