Hall-Effect IC Anchors Gear-Tooth Sensors

By converting movement to a digital signal, the MLX90217 Hall-effect IC enables a controller to determine speed, distance or rpm in automotive applications, industrial process equipment and other speed-sensing applications. The device, a rotary position gear-tooth sensor, features an on-chip, 10-bit A/D converter and logic that functions as a digital sample-and-hold circuit. A separate 4-bit A/D converter provides a fixed hysteresis. The chip's open-collector output is protected against short circuits. Accurate readings are provided over a wide range of conditions and at operating temperatures up to 155°C.