ATS665LSG

TRUE ZERO-SPEED GEAR TOOTH SENSOR

Final Version, Rev 1.0; DSD; 01Aug03

Page 10

SENSOR OPERATION: UPDATE

The ATS665 incorporates an algorithm that continuously monitors the system and updates the switching thresholds

accordingly. The switch point for each edge is determined by the previous two edges. Since variations are tracked in real

time, the sensor has high immunity to target run-out and retains excellent accuracy and functionality in the presence of

both run-out and transient mechanical events. The figures below show how the sensor uses historical data to provide the

switching threshold for a given edge.

Switching Level - Operate

Operate point

based on previous

two peaks

Switching Level - Release

Release point

based on previous

two peaks

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