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Entry type: FAQ Entry ID: 6060228, Entry date: 12/18/2000

Functions & Samples: artificial hysteresis on the analog comparator

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How can I influence the input sensitivity of an analog comparator?

The output of the analog comparator can be delayed selectively with the functions "ON delay" and "OFF delay". The effect is that the output is set only when the trigger value "Trg" is longer than the defined ON delay time "TH". When the output is set, it can be reset only when the trigger value is longer than the defined OFF delay time "TL".
This creates an artificial hysteresis which makes the input less sensitive to temporary changes.

The figure shows the switching setup.

The LOGO! project as a download:
The download contains the LOGO! project for the analog comparator described above. The project was created with LOGO!Soft Comfort V2.

KompHyst.exe ( 27 KB )

Copy the "KompHyst.exe" file into a separate directory and then start the file with a double-click. The LOGO! project unpacks automatically. You can then open and process the project with LOGO!Soft Comfort V2.

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