AR# 2945: 12.1 Timing Analyzer - How does Timing Analyzer calculate worst-case timing values if I do not know the temperature grade?
AR# 2945
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12.1 Timing Analyzer - How does Timing Analyzer calculate worst-case timing values if I do not know the temperature grade?
描述
How does Trace or Timing Analysis calculate worst-case timing values if I do not know the temperature grade for a part?
解决方案
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)