APS11900: Two-Wire End-of-Line Programmable Hall-Effect Switch/Latch

APS11900 devices are highly programmable, two-wire planar Hall-effect sensor integrated circuits (ICs) developed in accordance with ISO 26262:2011 (pending assessment). They include internal diagnostics that 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.

Programming can be performed at end of line to optimize the sensor on a per unit or per module basis. The user can select the magnetic switchpoints, temperature coefficient, and hysteresis,
and whether the device responds to north or south magnetic fields (unipolar switch) or both (bipolar latch or omnipolar switch). 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. In addition to a benchtop programmer (ASEK) for development and evaluation, universal software drivers are available to facilitate programming in a production environment.

APS11900 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 billof- 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 switch or latch is preferred, refer to the APS11500 and APS12400 device families, respectively.

TYPICAL APPLICATIONS

• Automotive and industrial safety systems
• Seat position detection
• Seat belt buckles
• Hood/trunk/door latches
• Sun roof/convertible top/tailgate/liftgate actuation
• Brake/clutch pedals
• Electric power steering (EPS)
• Transmissions and shift selectors
• Wiper motors

APS11900 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.

• Developed in accordance with ISO 26262:2011
  
  • Internal diagnostics and a defined Safe State
• Highly programmable
  • Magnetic polarity, switchpoints, and hysteresis
  • Temperature coefficient (supports SmCo, NdFeB, and ferrite magnets)
  • Output polarity and current levels
• Reduces module bill of materials (BOM) and assembly cost
  • Integrated overvoltage clamp (40 V load dump) and reverse-battery diode
  • Integrated series resistor and bypass capacitor (UC package)
  • Enables PCB-less sensor modules
• Automotive-grade ruggedness and fault tolerance
  • Extended AEC-Q100 qualification
  • Operation from –40°C to 175°C junction temperature
  • 3 to 24 V operating voltage range
  • High EMC/ESD immunity
  • Overtemperature indication