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Altera_Forum
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13 years ago

What is mean of fast/slow 0C/85C model?

There are three models in STA, it seems there is little reference from Altera to explain what is the mean of these and which is most important (I guess this depends on where the FPGA chip is used). S...
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Altera_Forum
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13 years ago

The actual timing characteristics of the chips are subject to PVT (process, voltage, temperature) variations.

Process: no two chips are equal. For a given FPGA speedgrade, some chips will be faster, some slower.

Voltage: higher Vcc makes the chip faster, lower Vcc makes the chips slower.

Temperature: lower T makes the chips faster, higher T makes the chip slower (0C is 0ºC, 85C is 85 ºC).

To ensure that the design will actually work in the real world, with different chips, subject variations in Vdd and different temperatures, STA tools usually run the analysis for 3 cases, known as corners: an extreme fast case, an extreme slow case and a typical case.