ICC 如何延遲net delay?

wenhsieh

請問在ICC如何在一條net或某個inst pin前精準地加個 1 ns 的delay?

liu675

set_input_delay ?

wenhsieh

回复 2# liu675


   謝謝,我是想問如何用BUF  來實現 我想加的delay 值

ZhouF

delay cell

cool_lovexia

不可能精准的加的，目前无法实现这种功能。即使在ICC中加入的buffer是1ns延迟，到了PT里面又不是1ns了

williamliwei

set_annotate_delay

小干爹z2z

回复 1# wenhsieh


   set_annotated_delaySets the net or cell delay value between two pins.
SYNTAX
status set_annotated_delay
-net |-cell
[-load_delay load_delay_type]
[-rise |-fall]
[-min]
[-max]
delay_value
-from from_pins
-to to_pins
[-worst]
Data Types
load_delay_type string
delay_value float
from_pins list
to_pins list


EXAMPLES
The followingexampleannotatesacelldelayof20unitsbetweeninputpin A of cell
instance U1/U2/U3 and output pin Z of the same cell instance. The delay value of 20
includes the load delay.
prompt> set_annotated_delay -cell-load_delaycell20\
-from U1/U2/U3/A-toU1/U2/U3/Z
The following example annotates a rise net delay of 1.4 units between output pin U1/
Z and input pin U2/A. The delay value for this net does not include load delay.
prompt> set_annotated_delay -net-rise-load_delaycell1.4\
-from U1/Z-toU2/A
The following example annotates a rise net delay of 12.3 units for minimum delay
analysis betweenthesameoutputpins.Inthiscasethenetdelayvaluedoesinclude
load delay.
prompt> set_annotated_delay -net-rise-min-load_delaynet12.3\
-from U1/Z-toU2/A

wenhsieh

我不是要在constraint 設delay 值,而是想實際用buf or delay 去墊出一個我想要的delay,
稍不準也沒關係

yahemao123

回复 8# wenhsieh


    那就insert_buffer啊，选用驱动能力比较小的
然后可以从以前的report中大概看出这个cell的迟延值大约有多大