SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
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Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#2How did SiFive get anywhere near 5nm TSMC?
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#3I know they're separate lines and capacity is sold well in advance and all that, but this chip shortage still baffles me.
A startup can tape out a 5 nm chip, but STMicroelectronics can't make any of their 40-130 nm microcontrollers for the next year?
Also car companies are supposedly the culprit, even though their volume is only in the low tens of millions per year, and the dustup is apparently over only six months of capacity? What? I get that the auto industry is a nice reliable long-term source of revenue for chip companies, but fabs should barely be sneezing at that sort of volume.
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#4How did SiFive get anywhere near 5nm TSMC?
perhaps paid some money when the process wasn't booked till the end of time
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#5How did SiFive get anywhere near 5nm TSMC?
For test chips there is something called shuttle.
Other than that, foundries are known to sponsor IP development on their processes.
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#6How did SiFive get anywhere near 5nm TSMC?
"The tape out means that the documentation for the chip has been submitted for manufacturing to TSMC, which essentially means that the SoC has been successfully simulated. The silicon is expected to be obtained in Q2 2021."
Would this mean the actual chip delivery may still be delayed?
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#7I know they're separate lines and capacity is sold well in advance and all that, but this chip shortage still baffles me. A startup can tape out a 5 nm chip, but STMicroelectronics can't make any of their 40-130 nm microcontrollers for the next year? Also car companies are supposedly the culprit, even though their volume is only in the low tens of millions per year, and the dustup is apparently over only six months o…
A lot of chips are made on mature fab lines because they don't need the performance of 5nm lines or can't justify the mask costs.
No one is investing in mature fab lines because they're not leading edge and they're being run to amortize the initial investmnet made into them years ago. Therefore not much additional capacity for mature lines.
So yes you can see 5nm chips being taped out but the 40-130nm chips are squeezed for capacity. Also this chip is likely not running in the same crazy volumes that ST microcontrollers. It is easier for TSMC to squeeze in a few dozen to a hundred wafers for SiFive on their line.
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#8How did SiFive get anywhere near 5nm TSMC?
It’s also in TSMC’s marketing interest to product a small number of RISC V parts with their latest process.
Plus it’s probably fun for some of the people there.
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#9I know they're separate lines and capacity is sold well in advance and all that, but this chip shortage still baffles me. A startup can tape out a 5 nm chip, but STMicroelectronics can't make any of their 40-130 nm microcontrollers for the next year? Also car companies are supposedly the culprit, even though their volume is only in the low tens of millions per year, and the dustup is apparently over only six months o…
This is an extremely low volume prototype run. You can get those scheduled on short notice. Fabs love them because they can do process optimization using them, without impacting production customers. They're ridiculously expensive per-die and you commit to accept a much higher failure rate than normal.
ST can and is making microcontrollers. It's just that they've sold their production for a year ahead, before it's even been manufactured. Car companies fucked everyone over by flipping a large volume of orders back and forth causing bullwhip effect on the whole industry, and lots of knock-on effects in other industries who suddenly got told (occasionally too late) that they need to plan their inventory a year ahead because they can't get anything at short notice anymore. Car companies vehicle production volume is tens of millions, but each vehicle has thousands to tens of thousands of ICs. The six months you are mentioning are not the capacity period, they are the lead times involved.
I don't want to repeat the whole story but I wrote a comment about this on another thread. See https://news.ycombinator.com/item?id=26659709
Re: SiFive Tapes Out First 5nm TSMC 32-bit RISC-V Chip with 7.2 Gbps HBM3
#10I know they're separate lines and capacity is sold well in advance and all that, but this chip shortage still baffles me. A startup can tape out a 5 nm chip, but STMicroelectronics can't make any of their 40-130 nm microcontrollers for the next year? Also car companies are supposedly the culprit, even though their volume is only in the low tens of millions per year, and the dustup is apparently over only six months o…
I'm in the semiconductor company.
I don't really understand your question.
Anyone can start a company and tape out a chip even in 5nm. My previous startup did something similar. We used an intermediate company between us and TSMC that specifically works with smaller companies. They (or TSMC) will bundle together 4 to 20 chips into a common mask as a "shuttle" run. Shuttle runs are really only used to get samples for the first version of your chip. You can't really go to production with them because the mask has chips from multiple different companies but this allows all of the companies to share the mask costs (I've heard up to $30 million for 5nm)
What is ST Micro talking about? I assume they can produce chips but can't get the volume that they want. SiFive are probably producing about 2,000 of these chips for development and test boards. ST Micro would be buying in the hundreds of millions or tens of billions range.