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# AR# 11556

## Description

A timing report (design statistic) is created after the Timing Analyzer launches. The design statistics account for terms such as:

- The maximum frequency of the design (minimum period)
- The maximum combinational path delay
- The maximum net delay

Does the "minimum period" refer to the entire design?

Is the "period check" from two flip-flops with the same clock?

Is the "period check" from two flip-flops with the same rise clock?

How is "maximum combinational path delay" calculated?

What is the difference between the "maximum combinatorial path delay" and the "maximum net delay"?

## Solution

Yes, theminimum period refers to the entire design. This line indicates the maximum clock frequency at which your design can run.

Yes, the period is checked from two flip-flops with the same clock (Highest clock).

Path and Net Term Definitions:

Path - An ordered set of elements identifying a logic flow pathway through a circuit. A path can consist of a single net or a grouping of related nets and components. Multiple paths (consisting of nets and components) can exist between the two pins.

When a component is selected as part of a path, both the input pin to the component and the output pins are included in the path. A path stops when it reaches the data input of a synchronous element (flip-flop) or pad. A path usually begins at the output of a synchronous element or pad.

Net - A logical connection between two or more symbol instance pins. After routing, the abstract concept of a net is transformed to a physical connection called a "wire."

The above definitions indicate that a path can consist of a single net or a grouping of related nets and components. The maximum combinatorial path delay is calculated as an estimation of the sum of all combinatorial time (delays) for each combinatorial stage in a path. Consequently, the maximum net delay is an estimation of the maximum connection time (delay) between two or more instance pins.
AR# 11556
Date 12/15/2012
Status Active
Type General Article
Tools
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