Question about syncpin & ignorpin define in CTS?

[hgby2209]

syncpin

what's dbDefineSyncPin & dbDefineIgnorePin 's mean?

which case must define as dbDefineSyncPin and
which case must define as dbDefineIgnorePin ?

Could anyone can tell me, thanks!!

 

[kvsidhi]

cts + sync pin

what's dbDefineSyncPin & dbDefineIgnorePin 's mean?

which case must define as dbDefineSyncPin and
which case must define as dbDefineIgnorePin ?

Could anyone can tell me, thanks!!

In Astro terms,

Ignore pins is the point where astro stops building tree generation . Astro CTS engine considers ignore pin as a leaf pin to be balanced with all other leaf pins.

Sync pin : Astro also considers a sync pin as a leaf pin to be balanced with all other leaf pins (flops clock pins) however user can specify a phase delay on sync pin.
If user set a point as a sync pin with 500ps phase delay, Clock tree would be generated such that the syncpin (point where sync pin is defined) would be actually lagging by 500ps with all other flops (leaf pins) in a perticulaer clock tree.

-Sidhi

 

[lailiya]

cts ignore pin

hi, Sidhi, how can i know the phase delay of a pin.

In our design, astro cann't recognize the clk pins of memory as sync pin, so we have to use dbDefineSyncPin to define the memory clk pins as sync pin, but we have no idea about the phase delay of memory clk pins, where can we get the information?

thanks