I am little bit confused about scanning

VLSI chip testing is done in several different places by different type of people .

scan in vlsi circuit used for testing VLSI circuit

Can anyone give some example ,
I mean If we are going to make micro controller, how we will scan circuit

 

I'm not sure, but I think you are referring to the following:

http://en.wikipedia.org/wiki/Boundary_scan

You keep omitting critical details and words from your posts. Would it kill you to write out coherent questions with all of the critical words included?

 

generally we scan PC to determine the virus

we scan vlsi circuit to determine fault

but what type of fault is determine by scanning

 

Did you read the article? All bets are off until you do that and specify that it is what you mean by "scanning" when it comes to hardware on a chip.

 

but what type of fault is determine by scanning

Manufacturing defects. Stuck-at faults, transition faults, etc.

Scan and Boundary Scan sound alike, but they are different tests. Which one do you mean?

This might help http://www1.verigy.com/cntrprod/groups/public/documents/file/gs_scanintro1of2.pdf

 

Hello vead

Well:
From this point of view: We scan PC to determine the virus.
We scan VLSI circuit to determine fault.

Like:
Open Resistors, coils, capacitors etc.
Failures in operational amplifiers, logic gates, transistors Etc.
open wires (tracks).
But also:
Operational amplifiers that do not meet their specifications as: propagation delay, slew rate, frequency response, etc..

In other words: We scan the VLSI to discover if they have any fault against their datasheets.
or:
If they meet the parameters established In its data sheet.

 

We can assume and infer all we want, but until the OP can pose a well formed unambiguous question we are just producing a lot of hot air.

He might mean scanning with an electron microscope or positron beams or some other exotic gee-gaw.