Angle sensor ICs’ diagnostics support safety critical operation
Two 0 to 360 degree angle sensor ICs from Allegro Microsystems provide contactless high-resolution angular position information based on magnetic Circular Vertical Hall (CVH) technology.
The A1337 and A1338 have an SoC architecture that includes a CVH front end, DSP, and digital SPI and SENT or PWM outputs. They also include on-chip EEPROM technology, capable of supporting up to 100 read/write cycles, for flexible end-of-line programming of calibration parameters.
Both devices are for automotive applications requiring 0 to 360 degree angle measurements, such as electronic power steering (EPS), seatbelt motor position systems, rotary PRNDLs, and throttle systems. The A1338 can be used for industrial motor position sensing applications that require high accuracy and minimal latency as well.
The A1337 and A1338 devices were designed for safety-critical applications, and include user-controlled, on-chip logic built-in self-test (L-BIST) and full signal path diagnostics to enable customers to determine if the IC is operating properly. Both devices support a low RPM mode for slower rate applications and a high RPM mode for high-speed applications. High RPM mode is for applications that require higher refresh rates to minimise error due to latency. Low RPM mode is for applications that require higher resolution operating at lower angular velocities.
The A1337 device also includes integrated turns counter and low power mode functions. The low power mode enables the device to be connected directly to the vehicle battery and minimises power consumption when the vehicle is in the key-off state. The turns counter function allows the device to keep track of either 45 or 180 degree turns of the motor when the part is in low power mode, allowing it to keep track of the motor position, even when the vehicle is in the key-off state.
The ICs are available in two package options, a single-die, 14pin TSSOP and a dual-die, 24pin TSSOP. Both packages are lead (Pb) free with 100 per cent matt-tin leadframe plating.