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hcom's avatar
hcom
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3 years ago
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Arria 10 (speed grade 3) has worse timing performance than Cyclone 10 GX (speed grade 5)

I am porting a design from a 10CX085YF67215G (Cyclone 10 GX, speed grade 5) to a 10AX022C4U19E3LG (Arria 10, speed grade 3). I am using Quartus Prime Pro Edition 21.3. The design meets timing in th...
  • hcom's avatar
    hcom
    3 years ago

    As confirmed by @RichardTanSY_Altera , this is expected behavior. Although it is totally baffling that a more expensive device family, combined with a superior speed grade leads to worse timing performance, I am satisfied that my question has been answered.

hcom's avatar
hcom
Icon for Occasional Contributor rankOccasional Contributor
3 years ago

I have found some documentation that seems to confirm that Arria 10 speed grade 3 has worse I/O timing performance than Cyclone 10 GX speed grade 5.

This is from p. 133 of "PHY Lite for Parallel Interfaces Intel® FPGA IP User Guide". I have highlighted the maximum interface frequencies:

It seems like a poor decision to name the speed grades this way. A superior device family (Arria) with a superior speed grade (3) has inferior timing performance to an inferior device family (Cyclone) with an inferior speed grade (5).