ATS617LSG Datasheet | Allegro MicroSystems

Dynamic, Self-Calibrating, Peak-Detecting, Differential Hall Effect Gear Tooth Sensor .. Features and Benefits - Self-calibrating for tight timing accuracy - First-tooth detection - Immunity to air gap variation and system offsets - Immunity to signature tooth offsets - Integrated capacitor provides analog peak and valley information - Low timing-accuracy drift with temperature changes - Low radiated emissions - Integrated, series resistor on VCC pin for improved transient immunity - Large air gap capability - Small, integrated package - Optimized magnetic circuit - Undervoltage lockout (UVLO) - Wide operating voltage range Description The ATS617 gear-tooth sensor is a peak-detecting device that uses automatic gain control and an integrated capacitor to provide extremely accurate gear edge detection down to low operating speeds. Each sensor module consists of a high-temperature plastic shell that holds together a samarium-cobalt magnet, a pole piece, and a differential opencollector Hall IC that has been optimized to the magnetic circuit. This small package can be easily assembled and used in conjunction with a wide variety of gear shapes and sizes. The gear-sensing technology used for this sensor module is Hall-effect based. The sensor incorporates a dual-element Hall IC that switches in response to differential magnetic signals created by ferrous targets. The sophisticated processing circuitry contains an A-to-D converter that selfcalibrates (normalizes) the internal gain of the device to minimize the effect of air gap variations. The patented peak-detecting filter circuit provides immunity to magnet and system offsets and has the ability to discriminate relatively fast changes such as those caused by tilt, gear wobble, and eccentricities. This easy-to-integrate solution provides first falling edge detection and stable operation to extremely low rpm. The ATS617 can be used as a replacement for the ATS616. Continued on the next...