Comparators internal hysteresis?

[jean_prieur]

Posted on May 11, 2012 at 12:06

Hello,

How works the internal hysteresis for comparators ?

Thanks for the support,

Jean

[Nickname14663_O]

Posted on February 17, 2014 at 15:35

Hi Jean,

The internal hysteresis is useful in order to suppress undesired output toggling. Moreover, it doesn't impact significantly the resolution of the comparator.

If the device doesn't include built-in hysteresis, or if a large hysteresis is required, a positive feedback network can be implemented as the following figure shows.

This figure shows that the high and low threshold voltages are different, thus a hysteresis configuration has been created.

It has been extracted from the application note

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00050759.pdf

Best regards,

Sylvain