Precision Hall-Effect Angle Sensor ICs Suits Automotive Apps

Allegro MicroSystems, LLC introduces a  family of contactless Hall magnetic sensors with the debut of its A1332 and A1334 high resolution 360° angle sensor ICs. Based on magnetic Circular Vertical Hall (CVH) technology, the A1332 and A1334 devices, with their system-on-chip (SoC) architectures, provide fast output refresh rates and low signal path latency to support a wide variety of demanding automotive and industrial applications. Both devices are ideal for automotive applications such as electronic power steering (EPS), transmission, motor position, throttle/pedal position, and other systems that require accurate measurement of angles.

The A1332, with an onboard 32-bit processor and EEPROM for factory and customer programmability, includes Segmented and Fourier linearization functions for supporting challenging off-axis/side-shaft magnetic sensing configurations that are commonly found in electronic power steering and transmission applications. The A1332 also supports on-axis/end-of-shaft magnetic sensing configurations and can produce high accuracy angle measurements at output refresh rates of 32µs. The device sports a 2-wire I²C digital interface with signal path and I/O diagnostics for achieving higher ASIL safety reliability objectives.

The A1334, with its onboard digital signal processing functions and EEPROM for factory and customer programmability, is designed specifically for on-axis/end-of-shaft applications that require ultra-fast output refresh rates and low signal path latency. Its 4-wire 10 MHz SPI interface offers a 25 µs output refresh rate and a nominal signal path latency of only 60 µs. In addition, the A1334 can operate directly off a vehicle battery, supporting a wide 4.5 V to 14.5 V supply voltage range, while consuming just 10 mA (max) of supply current. Like the A1332, the A1334 also includes signal path and I/O diagnostics for achieving higher ASIL safety requirements.

Both devices can operate in a Low RPM mode, to support up to 12 bits of output resolution in lower angular velocity applications, and in a High RPM mode to support situations demanding faster refresh rates and lower single path latency. As part of their signal processing functions, the ICs include automotive grade temperature compensation to provide accurate angle measurements over the full operating temperature and voltage range of the devices. The A1332 and A1334 are also air gap independent over a wide magnetic field range and can operate over a 300 G to 1000 G magnetic target field level, thus making them less sensitive to stray fields and ensuring high levels of accuracy. Their on-chip EEPROM technology also enables flexible programming of end-of-line calibration parameters.

The A1332 and A1334 operate over -40 °C to 8 5°C and -40 °C to 150 °C temperature ranges, respectively, and are production available as a single die in a 1 mm thin 14-pin TSSOP (LE suffix) package. For ISO26262 ASIL D safety critical systems requiring sensor redundancy, the A1334 is also sampling today in a dual die TSSOP-24 package, with production availability planned soon. All packages are lead (Pb) free with 100% matte-tin leadframe plating. The A1332 is priced at $2.98 and the single die A1334 is priced at $2.00, both in quantities of 1,000.