How To Verify Memory ??

[uditkumar1983]

Hi all,

I am having doubt that suppose you wants to verify IP of any RAM (or any other memory) than how you willl verify ?? you will go for randomization method or you will check all location of that memory ?

Thanks in Advance ..

Regards

 

[arunapai]

U can do one technique: Write AA to all byte locations once and 55 to all locations once. This checks the memory very easily and effectively.

This technique is used in Memory refreshing on all major devices.

 

[shiv_emf]

above mentioned trick is MBIST!! .....
mbist controller does same thing... writes and reads same value with different squence.. better go thru MBIST concept n implement in ur code !!

 

[uditkumar1983]

Hi
thanks for ur suggestion.
Regards

 

[pravin_dwaramwar]

Memories are tested by march algorithms.

 

[drizzle]

hi pravin

could u expand more about "Memories are tested by march algorithms"?

 

[shiv_emf]

writing and reading back frm same address location with many combinations of write read write .....etc

i will try to upload some material !!
shiv

 

[quan228228]

u can refer to MBIST user guide of SOLD to understand the concept and methods of memory test.

quan228228

 

[jammulak]

Write Data to memory and Checksum. or CRC.
Read the SAme and compute the checksum.

 

[dft_guy]

Here's a link to a good overview of memory bist - once ou understand the concepts, you can choose which method to apply to the memory you have!

www.ececs.uc.edu/~wjone/Memory.pdf

John
DFT Digest

 

[beyard]

write verilog code by self ..
just a FSM

 

[Fom]

MARCH is good enough. It is trade off between fault coverage and testing time (10*N).

Write0 from address 0...00 to F...FF (N)
(Read0 -> Write1) from address 0...00 to F...FF (2N)
(Read1 -> Write0) from address 0...00 to F...FF (2N)
(Read0 -> Write1) from address F...FF to 0...00 (2N)
(Read1 -> Write0) from address F...FF to 0...00 (2N)
Read 0 from address 0...00 to F...FF (N)
Totally 10N.