AR# 54561

Vivado Timing Analysis - How does Vivado timing analysis calculate worst-case timing values if I do not know the temperature grade?

Description

How does Vivado timing analysis calculate worst-case timing values if I do not know the temperature grade for a part?

Solution

If a military-grade part and a commercial-grade part are run at the same temperature, the military-grade part (which has the same speed grade as the commercial-grade part) is faster.

A part with a higher temperature grade (i.e., the military-grade part) will run up to the same speed at the maximum military temperature limit as a part with a lower temperature grade (i.e., the commercial-grade part) will run at its lower maximum temperature limit. If the military-grade part is run at the commercial temperature limit, it will be faster than the commercial-grade part at that same temperature.

When a Xilinx temperature-grade part is operated at its upper temperature limit, it is guaranteed to perform according to the worst-case delays indicated in its speeds file.

The Xilinx timing and simulation models are guaranteed under the following worst-case conditions:

  • Minimum Voltage (VCCINT or VCCO) - Ordering Information in the data sheet for each device family
  • Maximum Junction Temperature is in the Ordering Information in the data sheet for each device family

Output Loading:

50 pF (or capacitive loading for the default I/O Standard)

For additional information, see (Xilinx Answer 4235).
AR# 54561
Date 08/07/2013
Status Active
Type General Article
Devices
Tools More Less