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ATS685 : Two-Wire, Zero Speed Differential Gear Tooth Sensor IC

The ATS685 is an optimized Hall-effect sensing integrated circuit and rare-earth pellet combination that provides a user-friendly solution for true zero-speed digital gear-tooth sensing in two-wire applications. The sensor IC consists of a single-shot molded plastic package that includes a samarium cobalt pellet, a pole piece, and a Hall Effect IC that has been optimized to the magnetic circuit. This small package can be assembled simply and used in conjunction with a wide variety of gear shapes and sizes.
The single integrated circuit incorporates a dual element Hall-effect sensor IC and signal processing circuitry that switches in response to differential magnetic signals created by ferromagnetic targets. The device contains a sophisticated compensating circuit to eliminate magnetic and system offsets. Digital tracking of the analog signal is used to achieve true zero speed operation. Advanced calibration algorithms are used to adjust the device gain and offset at power-up, resulting in air gap independent switchpoints, which greatly improves output accuracy. In addition, advanced algorithms mitigate the effect of system anomalies such as target vibration and sudden changes in air gap.
The regulated current output is configured for two-wire operation. This sensor IC is ideal for obtaining edge and duty cycle information in gear-tooth–based applications such as transmission speed.
The ATS685 is provided in a 4-pin SIP package that is lead (Pb) free, with 100% matte tin leadframe plating.

Product Number: ATS685

Class: Sensors, Transducers Magnetic Sensors, Switches (Solid State)

Tag: Speed Sensors IC, Transducers Magnetic Sensors

Fully optimized differential digital gear tooth sensor IC
Running Mode Lockout
Unique algorithms for increased vibration immunity
AGC and reference adjust circuit
Air gap independent switchpoints
Digital output representing gear profile
Precise duty cycle throughout operating temperature range
Large operating air gap range
Short power-on time
True zero-speed operation
Undervoltage lockout (UVLO)
Wide operating voltage range
Internal current regulator for two-wire operation
Single-chip sensing IC for high reliability
Robust test coverage capability using Scan Path and IDDQ measurement

Typical Applications :

Part Number Output Type Features Sensing Range Mounting Type Test Condition Actuator Type Operating Supply Current Maximum Frequency Operating Temperature Voltage - Supply Package Type
ATS685 Open Collector Temperature Compensated 70% Trip, 30% Release Through Hole -40°C ~ 150°C External Magnet, Not Included 15.8mA 12 kHz -40 °C ~ 150 °C(TA) 4V ~ 24V 4-pin SIP (suffix SH)

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    Datasheet Download on May, 2020

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