The A1232 is a highly sensitive, temperature stable magnetic sensing device ideal for use in ring magnet based speed and direction systems in harsh automotive and industrial environments. It contains two bipolar, Hall-effect switches precisely arranged 1.63mm apart. The switch outputs are thus in quadrature when interfaced with the proper ring magnet design. Internal logic processes the resulting digital signals to derive speed and direction information that is presented at the device’s outputs, OUTPUT A and OUTPUT B.
The A1232 is designed for demanding, high performance motor commutation applications. The Hall elements are photolithographically aligned to better than 1µm. Accurately locating the two Hall elements eliminates a major manufacturing hurdle encountered in fine-pitch applications. The A1232 also has true power-on state (TPOS), the ability to detect when it is in the hysteresis band, beyond BOP, or below BRP at power-on. This provides reduced angle accuracy error due to missed start-up edges.
Post-assembly factory programming at Allegro provides sensitive, symmetrical switch points for both switches. Extremely low-drift amplifiers maintain this symmetry. The Allegro® patented, high-frequency chopper-stabilization technique cancels offsets in each channel and allows for increased signal-to-noise ratio at the input of the internal comparators. This leads to stable operation across the operating temperature and voltage ranges and industry leading jitter performance.
An on-chip regulator provides a wide operating voltage range. The A1232 is packaged in a plastic 8-pin surface mount TSSOP (LE). This gull wing style package is optimized for the extended temperature range of –40°C to 150°C. It is lead (Pb) free and RoHS-compliant, with a 100% matte tin plated leadframe.
