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This article mainly explains "how to use library scaling and scaling calculation". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Now let the editor take you to learn how to use library scaling and scaling calculation.

Application scenario: only a library of PVT, want check in another PVT, design's QoR, commonly known as library scaling. For example: only 0.9V125C library, want to see 1.0V125C timing, power.

Requirements: library support, tool support. To do scaling,library, there must be a "Derating" part, that is, the so-called K-factors. Today, there are about 33037 = (k_process + k_temp + k_volt) K-factors. With the progress of the process, more factor may be added. The Derating part is not necessary for library, nor does it need to define all the factor. The k_xxx listed in "Derating parameters" in the following figure is a part of the factor that needs to be used. Today's mainstream PPA-related implementation verification tools support library saling, but not all tools need to support all K-factors.

Calculation formula: scaled_value = total_scale * value_from_lib.

Where:

Total_scale = proc_scaling * temp_scaling * volt_scaling

Proc_scaling = 1 + K_proc * (current_proc-org_proc)

Temp_scaling = 1 + K_temp * (current_temp-org_temp)

Volt_scaling = 1 + K_volt * (current_voltage-org_voltage)

Such as:

Scaled_leakage_power = total_scale * leakage_power_from_lib

Scaled_cell_delay = total_scale * cell_delay_from_lib

Back to the above example, although the library listed a pile of k-factor, but very rogue are set to 0, so this library has its own table, can not do library scaling.

Tool side: take Genus as an example, you can do scaling based on a single library, or you can do scaling based on multiple library.

Example: single library

Set_attr library {{library1_PV1T.lib library1_PV2T.lib} {single_lib1.lib}}

Set_attr voltage V2 [get_attr active_operating_conditions /]

Example: multi library

Set_attr library {{library11.lib library12.lib} {library21.lib library22.lib}}

Set_attr voltage V3 [get_attr active_operating_conditions /]

At this point, I believe you have a deeper understanding of "how to use library scaling and scaling calculation". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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