ALLEGRO ATS616LSGTN-T

The ATS616 gear tooth sensor IC 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 package consists of a high-temperature plastic shell that holds together a samarium-cobalt pellet, a pole piece, and a differential open-collector 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 technology used for this circuit is Hall-effect based. The chip incorporates a dual-element Hall IC that switches in response to differential magnetic signals created by ferromagnetic targets. The sophisticated processing circuitry contains an A-to-D converter that self-calibrates (normalizes) the internal gain of the device to minimize the effect of air gap variations. The patented peak-detecting filter circuit eliminates 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-tooth detection and stable operation to extremely low rpm. The ATS616 can be used as a replacement for the ATS612LSB, eliminating the external peakholding capacitor needed by the ATS612LSB. The ATS616 is ideal for use in systems that gather speed, position, and timing information using gear-tooth-based configurations. This device is particularly suited to those applications that require extremely accurate duty cycle control or accurate edgedetection, such as automotive camshaft sensing. The ATS616 is provided in a 4-pin SIP that is Pb (lead) free, with a 100% matte tin plated leadframe. The ATS616 is a Hall IC/rare earth pellet configuration that is fully optimized to provide digital response to gear tooth edges. This device is packaged in a molded miniature plastic body that has been optimized for size, ease of assembly, and manufacturability. High operating temperature materials are used in all aspects of construction. After proper power is applied to the component, the IC is capable of instantly providing digital information that is representative of the profile of a rotating gear. No additional optimization or processing circuitry is required. This ease of use should reduce design time and incremental assembly costs for most applications. The package contains a single-chip differential Hall effect sensor IC, a samarium cobalt pellet, and a flat ferrous pole piece. The Hall IC consists of 2 Hall elements (spaced 2.2 mm apart) located so as to measure the magnetic gradient created by the passing of a ferromagnetic object. The two elements measure the magnetic

• Self-calibrating for tight timing accuracy
• First-tooth detection
• Immunity to air gap variation and system offsets
• Eliminates effects of signature tooth offsets
• Integrated capacitor provides analog peak and valley information
• Extremely low timing-accuracy drift with temperature changes
• Large air gap capability
• Small, integrated package
• Optimized magnetic circuit
• Undervoltage lockout (UVLO)
• Wide operating voltage range

• systems that gather speed, position, and timing information using gear-tooth-based configurations
• applications that require extremely accurate duty cycle control or accurate edgedetection, such as automotive camshaft sensing