DS25BR440: LOS signal

Yuki

1. Please tell me "LOS pin is asserted when no signal is detected at input" 's specific conditions, what is identifed as "no signal"?

When an open input fault condition is detected at the input,

2. Please provide the time from meet LOS assert condition to assert signal output.

Please see this e2e link, https://e2e.ti.com/support/interface-group/interface/f/interface-forum/851769/ds25br440-ds25br440-output-data-response-with-pwdn. 

Thanks

David

Hi David

Thanks so much for your help.

About "an open input fault condition is detected at the input", is it detected the relationship between pos, neg signal and vcom voltage?
Could you tell me more detailed information about this area?

Thanks so much.

Best regards,
Yuki

Yuki

There is fail/safe circuit which biases the input such that when there is no signal or open inputs LOS pin will not toggle and it is asserted.

Thanks

David

Hi David

Thanks so much for your help!

Could you confirm the following picture and descriptions？

(1) LVDS input is H fixed
(2) LVDS input is toggle（100~200MHz）=> Can it be guaranteed that the LOS signal will not toggle?
(3) LVDS input is opened in halfway (connect cable is cut off, etc.) => LOS is asserted after OPEN detection 200 ns
(4) LVDS input is opened (connect cable is cut off, etc.)

Please tell me whether my above understanding is correct.

If there is any problem, please let me know.

Thanks so much.

Best regards,
Yuki

Yuki

Your understanding is correct.

Thanks

David

Hi David

Thanks so much for your confirmation!

About the second item of the above questions:
(2) LVDS input is toggle（100~200MHz）=> Can it be guaranteed that the LOS signal will not toggle?

Is it correct that "it can be guaranteed that the LOS signal will not toggle"?

Best regards,
Yuki