Push-pull, unipolar Hall switches save board space in battery-powered applications

Diodes Incorporated introduces two new portfolios of monolithic, unipolar Hall-effect switches designed for proximity sensing in battery-powered applications. With an ultra-low 1.1µA supply current at 1.85V, and 1.6µA at 1.6V to 5.5V, these devices are ideal for battery-powered portable equipment like smartphones, laptops, and wearables. The devices are also suitable for domestic appliances, game consoles, and industrial hardware use.

The 1.6V to 5.5V operating voltage of these Hall-effect switches allows them to be powered directly from a portable device’s battery, eliminating the area and cost of power conversion. Output 1 in the dual-output AH139x series responds to a North pole, while Output 2 responds to a South pole with typical operating points of 25G (AH1391) and 30G (AH1392). The single output on the AH138x series responds to a South pole on the part-marking side with typical operating points of 18G (AH1381), 30G (AH1382), and 45G (AH1383).

The tight operating window of these switches ensures a lower magnetic spread, while their chopper-stabilised design provides minimal switch point drift and superior temperature stability. For robustness, these devices have strong human body model (HBM) electrostatic discharge (ESD) protection: 8kV for the AH138x and 6kV for the AH139x series. In addition, these devices have push-pull outputs that do not require an external pull-up resistor, simplifying system design, saving board space, and lowering the bill of materials.