isolation with lowest response time in digital signal

Hi Brinda, I read your request and reply, so you have an PWM signal @50Hz or is something different?
"very less response time" has no sense so what this mean?
How is waveform of input signal?
What are the parameter to be read from?
What measurement you intend to perform?
What precision of which measure you need?
Why isolation is needed?
Comparator (fast one) can do the job of capture edge from your input?
If so select a Comparator can match all data mentioned then an  ISO interface from this page maybe can do the job

http://www.ti.com/lsds/ti/isolation/digital-isolators-products.page

or try ISO7421

No detail no precise answer.

hii roberto,

yes i have PWM signal with 50Hz frequency. the thing is i have to operate my another outputs when that PWM cross the zero. So this PWM signal will be my INPUT signal for the further processing. As that PWM signal is from analog circuit i have to have some isolation for over voltage protection. 

About waveform, the power line which is so much disturbed is feeded to comparator and than i have to figure out the zero crossing of that PWM.

Thank you for your support.

Have a nice day.

Brinda shah

In our term zero crossing is when an analog signal level cross the zero line, I suppose you have a different stuff you are unable to express.
I suppose you have a power line signal from unknown device that has 50% duty cycle referred to sinusoidal power line  and you call this  PWM. If so this signal reveal zero crossing power line on both edges.
Again very less has no sense:
Very low response time? Again you have to evaluate jiitter? have to precisely do something on zero crossing? Have to do phase regulation on Triak?
Please be more precise on what your phrases means.

Roberto,

Acknowledge your great efforts in "trying" to assist - but elephant lurks - this unruly/undisciplined room...

Is this truly a vendor's MCU issue - at all?   Seems more basic signal processing - w/ signal levels incompatible w/any MCU - more "engineering" issue than MCU one.

And - resources directed to these "strange, one-off requests" - steer the forum from the "much needed" MCU focus.

Is the uDMA explained and/or detailed to anyone's satisfaction?  New 129 family forces changes to I2C handling.  PF0/PD7 (still) lurk!  And USB - minus Tsuneo's active participation - may be listed as, "Not quite ready for prime-time."   And there's more.

Thus - diluting an already limited (one man) forum resource - may not reveal "best/brightest" forum resource management.

Poster guidance - proper (enforced) MCU-centric issues only - and far greater depth & detail in the description & management of the more complex MCU peripherals - seems a far better prescription for long-term, MCU Forum success than, "Flood-gates open - ANY question invited!"

Dear sir,

I probably not using the correct words to describe my problem or probably not using the correct reference. But I am in doubt and i thought TI can help me. Thats why in no other option i have posted here for the request. Not in purpose of wasting your time. If that is so I am heartily sorry for doing that.

My friend - you are not alone in such posts - and you must agree - they are not (strictly) MCU related.

My time - and that of other outsiders - is not at issue. But the single vendor presence here is - and questions which are far more weighted toward basic engineering (as yours clearly is) should be better directed.

Vendor here (or Vishay - as Amit suggested) must have a components section - that would be my "better, issue focused" destination.

As earlier detailed - many (strictly) MCU issues here require far greater explanation, detailing, clarification.  In my 8+ years here - yours is (maybe) the 2nd or 3rd such post at/near your subject.   And - beyond your post's "rarity" note that, "not one page" of the 1000+ page MCU manual delves into, "outside world" signal preparation/conditioning - for introduction to the MCU.  (absolute max. values, not withstanding)  Is that fact not - in itself - most telling?

Are NO subject limits to be applied/enforced?   Should not (some) here be thinking along these lines - and trying to maximize this forum's effectiveness?

MR/MS Brinda, till you don't specify what problem you have and we can reroute to isolator or proper area we (Amit too) CANNOT help!

Please FULLY GRASP till description of your side request is not understandable, nor TI, Vishay Toshiba, OnSemiconductor, ST nor other can solve for you what none don't know but you.

I agree CB1, this is not TIVA Related and need be directed to another specialized TI or competitor forum.

I am so sorry with what you provide this forum is helpless and I have to agree CB1 too also if you don't grasp what it mean.

I am sorry BUT

------------ NO DESCRIPTION OF WHAT IS QUESTION DON'T HELP US UNDERSTAND!!!

----- WE CANNOT HELP ON  WHAT WE DON'T KNOW!

 Please accept we are so sorry but fault is at your side. Provide detailed description and we can try help.

Brinda Shah said:

I probably not using the correct words to describe my problem or probably not using the correct reference. But I am in doubt and i thought TI can help me. Thats why in no other option i have posted here for the request. Not in purpose of wasting your time. If that is so I am heartily sorry for doing that.

 Hi Brinda, here is question of not waste at all time starting from your. We ask describe, we try help, we ask again but please try describe what is your request /issue.

 As I wrote no description no help, don't get our word as offensive, they aren't we don't have magic bowl and if we have we need respect privacy of others.

 Forum get useless if not focused and simple to use.

cb1- said:

Acknowledge your great efforts in "trying" to assist - but elephant lurks - this unruly/undisciplined room...

 Hi CB1, thank for appreciation, but IMHO I feel up we cannot do nothing to these request nor apologizes when them seems our answer as offensive than a desperate attempt to solve something impossible to solve due to complete lack of information or generic word out of topic.

 This is the most frequent and  worst forum failure and forever this area I insist need be splitted to save real TIVA issue and hint.

 I learn in some country someone call rectangular wave "PWM", we found this inappropriate term too many times when pulse duration or edge sync where appropriate. So I am not native too and I can also do mistakes and error. When I am tired of work I sometimes wrote some horrible phrases when I read I got frozen by...

 But forever this forum require discipline or some magic art too we never can refine ;)

Roberto Romano said:

IMHO I feel up we cannot do anything to these request nor apologize...

Perhaps (not we) but the forum can, "Preserve, protect & defend" it's MCU "raison d'etre" by simply enforcing with, "Post NOT adequately MCU focused!"

In its present, unguided, undirected form - a very wide (too wide imho) net is cast - and many (unwanted) far off "MCU topic" posts arrive - and are accepted!

That's the problem - some "toughness" is the solution.

Yes it's great to "help everyone."   But is that (at all) realistic?  

And - do efforts (regularly devoted) to far-off MCU topics make sense - when uDMA, USB, I2C, SPI, and EPI "cry out" for greater explanation - far more in-depth App Notes - and complete (well commented) programming examples?  Forum management chooses "what to do" - casting too wide a net has not proved, "best/brightest!"

cb1- said:

And - do efforts (regularly devoted) to far-off MCU topics make sense - when uDMA, USB, I2C, SPI, and EPI "cry out" for greater explanation - far more in-depth App Notes - and complete (well commented) programming examples?  Forum management chooses "what to do" - casting too wide a net has not proved, "best/brightest!"

 I feel as too few people come here for professional use of this MCU, this case is this to be avoided as professional and leave as it was an Arduino and accept every children request like the latest one asking to have basic beginner request of HTML code tailored for him?

 This cannot be sustained. This thread has something related to TIVA poster is using but is completely unreadable and posted (probably as poster assume himself) in wrong worded mode.

 What is scaring me as professional user is the lack of topic digging information of real issue and not false "issue" "not working" "failure" "Do all needing to made my code working"..... "VERY URGENT RESPOND IMMEDIATELY!!!!"" ..........

 I am tired of and this scare me if real problem can appear, yes we can ask our good Amit but divided by so huge request has no resource to serve us, in the area of peripheral I am using, after ETH module, I seen nothing more real issue. This is still a new product and some feedback than noise is a must.