Design – Page 4 – VLSI System Design

7th mile-stone in open-source analog IP design – 10-bit DAC

Ashutosh had joined our VSD Research IP design internship group 8-weeks back, along with 30 other interns. His journey on was from “I can’t, its too difficult” to “I did it”. Personally, only I know how hard it was for him when he saw an industry grade 10-bit DAC specifications on VSD IP website. We managed to achieve post-layout DNL of 3.5LSB and INL of 3.7LSB, which as per experience, is really tough for a fresher to achieve in a span of 8-weeks, but not impossible.

6th mile-stone in field of open-source – FREE VLSI tool installation course

A full-fledged video lectures on step-by-step process to install OpenLANE EDA tool chain and Sky130 PDK open-process on your own laptop, from scratch. There is a dependency on vsdflow, though for fresh users and with Windows or fresh Unix machines. To do something like this, it needs a clear focus on end vision, with very good VLSI fundamentals, which demands hours of efforts every day

5th mile-stone in field of open-source – another compact SRAM

This time its @Reuel did a pretty great job of building a pretty compact 6T-SRAM cell and he is just a third year engineering student

4th mile-stone – 35 RISC-V cores in 5-days – Can you believe it?

We had Makerchip IDE, TL-Verilog, Day wise Slack channels, Classroom GitHub and VSD-IAT – All of them so seamlessly integrated that every participant followed the loop and there you go. Out of 110 participants, 35 participants built entire basic RISC-V CPU core which is close to 30% participants, and all in 5-days

3rd mile-stone in 1-week in field of open-source – 4kB SRAM design

@Yash joined our research project group under VSD Research internship program which runs for 8-weeks. He was supposed to explore openRAM memory compiler flow, develop all custom cells required by openRAM using OSU180nm and generate 4kB SRAM with an access time of 2.5ns

2nd mile-stone in field open-source (open-lane EDA + Google/Sky130)

@Nickson joined our research project group under VSD Research internship program which runs for 8-weeks. He was supposed to develop flow for standard cell design and characterization using all open-source tools – magic/ngspice, then plug those standard cells into open-source PNR flow by open-lane, and benchmark RTL2GDS flow results. This needed a knowledge, not only of PNR, but device physics, custom layout, DRC/LVS and then (finally) Physical design/STA.

Mixed-signal PNR flow using openlane/sky130nm process

GitHub is the new Resume for VLSI industry

The horrible std cell ever designed by me….

Power rail discontinuity – We would like to have continuous power rail.N- and P-diffusion discontinuity – We would like to have continuous diffusion. For my Physical design friends, remember, we add “FILLER” cells at the end of routing, and you always wondered why we are doing so.Small substrate contacts – Except for inverter, all substrate contacts are single width, which will create high resistance path for current, thus increasing “Clk-to-Q” delay.Hanging metal1 – If you see for the NAND gate outputs, there is lot of hanging metal1.

‘Made in India’ SHAKTI processor on VSDFLOW – Now that’s exciting

With learning being online, SHAKTI core and ‘vsdflow’ being opensource, this is first-time in the history of VLSI design & EDA (thanks to RISC-V ecosystem and Shakti Team at IITM lead by Prof. Kamakoti), a chip will ever be taped-out using all open source flow, which will cater to almost 80% Indian Semiconductor Market.

Keynote 1(Continued): Inception of Intel 8086

It wasn’t that bigger deal for Intel because they thought, at the time, it will be 250,000 chips will be sold for 5 years, which isn’t that many. But they were wrong. It was a 100Million computers were sold. And suddenly 8086 from being an emergency back-up was an over-night success and had a very bright future, because it was binary compatible of PC software, and so had great opportunity

Isn’t that an inspiring story?