Timing - Creating Relative Propagation Delay

Creating Match Groups in CCS is as easy as ... 1 2 3.

1. Create Match Group

2. Add PinPairs to the Match Group

3. Define the Match Group Timing type - Simple Match, Match with Target, Relative Timing.

The VISUEYES parametric display shows you the timing relations as your timing constraints create them. You see the timing as you make the timing.

Correct by Design - first time, every time.

Create Match Group

The first step is to select Nets and XNets for the Match Group, and to then create the Match Group.

Add Pin Pairs to Match Group

Choose Pin Pairs from the selected Nets and XNets and add to the Match Group.

Create Simple Match Timing

This timing has no Target, Delta is blank.

The Tolerance is the same as the Match Range.

Choose Type of Rel Prop Timing

Choose the type of Rel Prop Timing from the three types:

  • Simple Match

  • Match with Target

  • Relative Timing

CCS will automatically setup your Match Group with the correct Delta value for each type of timing.

You can change and adjust the timing type and Delta at any time.

Create Match with Target

This timing has the Target in the center of the Match Group.

The Pin Pairs are +/- Tolerance of the Target.

Delta = 0.


The Match Range is twice the Tolerance.

Pin Pairs in Multiple Match Groups

Pin Pairs can be in multiple Match Groups.

Selecting a Pin Pair in CCS that is in multiple Match Groups will automatically load all the Match Groups for that Pin Pair.

You can toggle through all the Match Group in the VISUEYES Rel Prop Display.

Create Relative Timing

This timing has a Target, at least one non-zero Delta and one or more Tolerances.

It describes any type of Relative Timing.

VISUEYES displays the timing to verify for you that your constraints will produce the timing Design Intent you want.