What are the differences of ATPG engines?

[paparoulis]

Tetr@m@x engines

Hi all
Anobody knows the difference among atpg engines?
says basic scan for scan and sequential for memory elements (ff/latch/mem)
but when i use sequential engine on combinational design i get better coverage than basic scan
shouldn't be the same? any ideas?

 

[kevine]

Tetr(at)m(at)x engines

accoding to my experience,using sequential engine cost more time than combinational engine,and the coverage is less than combinational engine.usualuuy,I use combinational engine to do full scan rather than sequential engine .

 

[linuxluo]

Re: Tetr@m@x engines

hi,
yes , if your basci atpg can got good coverage, you can try fast-seq, it will increase coverage becoz using seq atga engin. but normally do not try full-seq atpga mode becoz it need much more run time and increas coverage maybe a little

 

[dr_dft]

Tetr(at)m(at)x engines

Prof. CW Wu from National Tsing-Hua University has done extensive research on Flash memory testing. Check out his lecture notes under
**broken link removed**

A link to this can be found under **broken link removed**

Added after 5 minutes:

Oops, wrong reply.
But in general, basic scan only does
shift in -> pulse clock once (capture) -> shift out
Thus, if you have any non scannable flip-flops or latches, there will be some faults that we not be detected. With a sequential engine, multiple capture cycles are allowed in between scan shifts, thereby giving the ability to propagate fault effect across non-scannable flip-flops, and hence increasing coverage.
Hope this is clear.