Three-Wire Zero-Speed Differential Peak-Detecting Sensor IC with Continuous Calibration



Top Features


The A17301 integrates a single IC and EMC components into a small SIP package, providing a robust and cost-effective solution for digital ring-magnet sensing or ferromagnetic target sensing when coupled with a back-biasing magnet. The device can be used in two-wheeled vehicle applications where a wide variety of target shapes and sizes are used. The A17301 is ideally suited to obtain speed and duty cycle information for position and timing applications, such as in speedometers/tachometers.


The integrated circuit incorporates dual Hall-effect elements with 2.2 mm spacing and signal processing that switches in response to differential magnetic signals created by ring-magnet poles. The circuitry contains a sophisticated digital circuit to reduce system offsets, to calibrate the gain for air-gap-independent switch points, and to achieve true zero-speed operation. Running mode recalibration provides immunity to environmental effects such as micro-oscillations of the target or sudden air gap changes. Use of a digital peak detector for output switching control ensures the part is robust to input signal changes, regardless of the amount of signal shift between output edges.


The A17301 is available in a 3-pin SIP (suffix UC). The package is lead (Pb) free, with 100% matte-tin lead frame plating.

  • Zero-speed operation 
  • Integrated capacitors for EMC performance
  • Immune to common external magnetic disturbance
  • Operates down to 20 Gpk-pk differential input field for large air gaps or small back-biasing fields
  • Running mode recalibration after start-up vibration ensures immunity to possible target anomalies
  • Accurate duty cycle on output signal throughout operating temperature range and air gaps

Part Number Specifications and Availability