(Image courtesy of Allegro Microsystems).
Allegro MicroSystems recently introduced a new family of contact-less, Hall-effect-based magnetic sensor ICs for high speed motor position sensing applications. Allegro's dual-die A1331 and A1334 angle sensor ICs are based on vertical Hall-effect technology. The A1331 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.
The dual die A1331 and A1334 ICs are offered in a TSSOP-24 package that contains two individually sawn, electrically isolated silicon ICs. These dual die ICs are ideal for use in safety critical applications that require the use of redundant sensor ICs, especially in ASIL compliant systems.Both devices are ideal for automotive applications such as electronic power steering (EPS) or power braking motor position sensing, transmission actuator position sensing, throttle/pedal position detection, and other systems that require accurate measurement of angular or rotary position.
The A1331 and A1334, with their onboard digital signal processing functions and EEPROM for factory and customer programmability, are designed specifically for on-axis/end-of-shaft angle sensing applications that require ultra-fast output refresh rates and low signal path latency. These ICs offer a 4-wire 10 MHz SPI interface with a 25 µs output refresh rate and a nominal signal path latency of only 60 µs. In addition, the ICs 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 per silicon die. These dual die ICs also include signal path and I/O diagnostics designed to meet the needs of stringent ASIL safety requirements.
Both devices can operate in a Low RPM mode, to support up to 12 bits of output resolution, 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 (-40°C to 150°C) and voltage range (4.5 V to 14.5 V) of the devices. The A1331 and A1334 output signals maintain a high level of accuracy over a wide magnetic field range, and can operate over a field range of less than 300 G to greater than 1000 G. On-chip EEPROM technology also enables flexible customer programming of the ICs.
