The SS40AF-2 is an open-collector, Hall-effect, solid-state switch manufactured by Honeywell. It senses the presence of a magnetic field and switches the output voltage from low to high. It is housed in a TO-92 package and is RoHS compliant, meaning it is free of hazardous substances such as lead, cadmium, and mercury. It features a wide operating temperature range of -40 to +130°C, which makes it suitable for use in automotive, industrial, and consumer applications. The device is aimed at providing reliable, cost-effective operation, low power consumption, and robust signal conditioning for many applications such as mobile phones, battery management, power tools, and security systems.