SoC designers are at ease to compare the performances of memories. It indeed only requires selecting some memory capacities and checking that performances are provided in the same conditions among the suppliers. Area, speed (access time), power consumption in dynamic mode and leakage may be then objectively compared.
What about Standard Cell libraries? Not an easy process…
All designers go with their own method: comparing directly by applying on their own design, merely comparing the nand2, trying to evaluate with key figures… but it is quite uncomfortable to compare products when there is no public benchmark and when the particularity of each library must be mastered for a fair comparison. The burden of performing a synthesis followed by the place and route, while learning at the same time how to make the best use of the new library, curbs the enthusiasm of most designers to check whether a new library could help improve the competitiveness of their next SoC.
The launch by Dolphin Integration of Motu-Uta, the first public benchmark for standard cell libraries, lifts the burden of evaluation for suppliers, users or foundries. Designers simply need to request from each library supplier the delivery of a complete set of performances to objectively compare their performances in less than 15 minutes!
What is Motu-Uta?
Motu-Uta (besides being the Tahitian holy island) names the first public RTL synthesizable and process independent benchmark for standard-cell libraries. It is made of typical RTL logic blocks with diverse critical paths (register-decoding-register, register-ALU-register) and with random combinatorial logic to be representative of a typical logic block of nowadays SoCs. The Motu-Uta benchmark is delivered with a testbench to compare the achievable power consumption as well as speed and area. It is also provided with “benchmarking conditions” of reference so that each supplier discloses performances for its standard-cell library truly in the same conditions, to enable a fair and objective comparison within minutes.
Expert designers may also take advantage of Motu-Uta benchmark to draw the hockey stick curves of any standard-cell library: area against clock frequency or dynamic power consumption against clock frequency, as illustrated below with Dolphin Integration’s 6T library versus a standard 7T library.
Motu-Uta V5 benchmark using 7 metal layers
Synthesis performed in SS; 1,08 V; 125°C
P&R performed using multi-corner and multi-mode at nominal voltage
Standard cell library providers may now promote the superior performances of their library without worrying about benchmarking tricks.
Accordingly, Dolphin Integration provides the benchmarking results for its standard cell libraries, especially for the celebrated Spinner cell advantage (Sesame uHD), on: My Dolphin.