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Gagilan
Level 1
Level 1
5 replies posted 10 sign-ins 5 sign-ins

what's the different of speed senor's :

Type of Hysteresis : hidden fixed; hidden adaptive; visible fixed; visible adaptive

TLE4941, TLE4943, TLE4953, 

Thanks

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1 Solution
Sunil_P
Moderator
Moderator
Moderator
First question asked 100 replies posted 10 likes given

Hello @Gagilan ,

Hysteresis is classified into Adaptive hysteresis and Fixed hysteresis, which is further divided into visible hysteresis and hidden hysteresis. 

Let me try to explain term "Hidden Adaptive hysteresis", which will help you self understand other similar terms.

Hidden hysteresis concept introduces two additional thresholds above and below the switching threshold of the sensor product. 

Sunil_0-1698314744202.png


Hysteresis
means that the magnetic field has to pass not only the switching threshold to put a switching edge to the output “Q” but requires one additional crossing of a hysteresis threshold. Additionally, positive and negative hysteresis thresholds has to be passed alternatively.

In Figure the first red dot indicates the crossing of the switching threshold which directly responds into a
switching event at the output “Q” since the positive hysteresis threshold was crossed before.
Following crossing of the switching threshold due to noise will not lead to any output edges since no hysteresis
threshold was exceeded in between.
After some noise is as big as exceeding hysteresis threshold and switching threshold one additional output-pulse is generated at output-pin “Q”.
Further noise will be ignored since the positive hysteresis threshold was not crossed. After crossing the positive
hysteresis threshold the output “Q” is enabled again and a corresponding falling edge is visible.

As soon as there is no noise in the system, the output switches when the switching threshold crosses zero.
The strength of this implementation is avoiding additional switching on noise and minimizing additional
switching due to vibration to maximum one pulse. Of course as soon as vibration is as big as one tooth this can not be recognized by the system any more.

Hidden hysteresis means described functionality with two hysteresis threshold not visible at the output during
normal operation.
Adaptive hysteresis describes an adapting hysteresis level depending on the amplitude of the magnetic field of
the last detected teeth.

Similar to the above explanation you can easily get to know other related terms.

BR
Sunil. 

View solution in original post

4 Replies
Sunil_P
Moderator
Moderator
Moderator
First question asked 100 replies posted 10 likes given

Hello @Gagilan ,

Hope i am getting your question correctly.

TLE4941C  - Hidden fixed
TLE4941PLUSC - Hidden fixed

TLE4943C - Hidden adaptive

TLE4953 - Visible adaptive

If you have further questions let me know.

BR
Sunil.


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Hi Sunil, Thanks a lot for your support, but i think it's maybe not very clear for my question.

what's i want to know is what's the different between the Type of Hysteresis : hidden fixed; hidden adaptive; visible fixed; visible adaptive.

0 Likes
Sunil_P
Moderator
Moderator
Moderator
First question asked 100 replies posted 10 likes given

Hello @Gagilan ,

Hysteresis is classified into Adaptive hysteresis and Fixed hysteresis, which is further divided into visible hysteresis and hidden hysteresis. 

Let me try to explain term "Hidden Adaptive hysteresis", which will help you self understand other similar terms.

Hidden hysteresis concept introduces two additional thresholds above and below the switching threshold of the sensor product. 

Sunil_0-1698314744202.png


Hysteresis
means that the magnetic field has to pass not only the switching threshold to put a switching edge to the output “Q” but requires one additional crossing of a hysteresis threshold. Additionally, positive and negative hysteresis thresholds has to be passed alternatively.

In Figure the first red dot indicates the crossing of the switching threshold which directly responds into a
switching event at the output “Q” since the positive hysteresis threshold was crossed before.
Following crossing of the switching threshold due to noise will not lead to any output edges since no hysteresis
threshold was exceeded in between.
After some noise is as big as exceeding hysteresis threshold and switching threshold one additional output-pulse is generated at output-pin “Q”.
Further noise will be ignored since the positive hysteresis threshold was not crossed. After crossing the positive
hysteresis threshold the output “Q” is enabled again and a corresponding falling edge is visible.

As soon as there is no noise in the system, the output switches when the switching threshold crosses zero.
The strength of this implementation is avoiding additional switching on noise and minimizing additional
switching due to vibration to maximum one pulse. Of course as soon as vibration is as big as one tooth this can not be recognized by the system any more.

Hidden hysteresis means described functionality with two hysteresis threshold not visible at the output during
normal operation.
Adaptive hysteresis describes an adapting hysteresis level depending on the amplitude of the magnetic field of
the last detected teeth.

Similar to the above explanation you can easily get to know other related terms.

BR
Sunil. 

Dear Sunil,

got it.

Thanks a lot for your kindly support.

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