Two-Wire Hall-Effect Latch

APS12400 devices are two-wire planar Hall-effect sensor integrated circuits (ICs) that include internal diagnostics and support functional safety. The enhanced two-wire current-mode interface provides interconnect open/short diagnostics and adds a Safe State to communicate diagnostic information while maintaining compatibility with legacy two-wire systems. Two-wire sensors are well-suited to safety applications, especially those involving long wire harnesses.

The APS12400 is a factory-calibrated latch (bipolar switch) available in several product options including magnetic switchpoints, temperature coefficient, and output polarity. The response can be matched to SmCo, NdFeB, or low-cost ferrite magnets. There is a choice of two output current levels and either output polarity.

APS12400 sensors are engineered to operate in the harshest environments with minimal external components. They are qualified beyond the requirements of AEC-Q100 Grade 0 and will survive extended operation at 175°C junction temperature. These monolithic ICs include on-chip reverse-battery protection, overvoltage protection (40 V load dump), ESD protection, overtemperature detection, and an internal voltage regulator for operation directly from an automotive battery bus. These integrated features reduce the end-product bill of materials (BOM) and assembly cost.

The available SIP package with integrated discrete components (UC) enables PCB-less applications by incorporating all of the EMC protection components into the IC package. Other package options include industry-standard surface-mount SOT (LH) and throughhole SIP (UA) packages. All three packages are RoHS-compliant and lead (Pb) free with 100% matte-tin-plated leadframes.

For situations where a functionally equivalent but factory-programmed two-wire latch or end-of-line programmable device is preferred, refer to the APS12400 and APS11900 device families, respectively.

APS12400 was developed in accordance with ISO 26262:2011 as a hardware safety element out of context with ASIL A capability (pending confirmation) for use in automotive safety-related systems when integrated and used in the manner prescribed in the applicable safety manual and datasheet. For further information, contact your local Allegro field applications engineer or sales representative.