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Comment by lnsru | Hacker News Reader

Price is a bit high, but factory lead time of 1 week is amazing! Also very interesting Product Change Notification: “0.6μm process currently being used at TSMC”. Interesting, that TSMC still used such ancient node in 2013.

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> Interesting, that TSMC still used such ancient node in 2013.

I guess for these type of products, where the wafers is not what costs (the 6502 is ~3.5k transistors), but overheads of dealing with small runs and packaging or investing in upgrades...

Anyone looking for large quantities of 6502-compatible cores presumably are mostly licensing cores to embed into something else.

Sure, the node is ancient, but the factory is long ago written off which means that (aside from energy, materials and labor expenses) all income is pure profit. As long as there are enough orders to cover the expenses plus a couple percent of profit margin, it makes sense to continue operating that factory.

Lower-resolution nodes are still very useful for analog parts - transistors, regulators, op-amps and so on.

I suspect that is to make it as close to compatible to the original as possible with respect to its ability to resist EM interference. Lots of chips from the 80's and 90's ended up in military hardware and some of that stuff is still being manufactured or in use. I wonder if a milspec 6502 version was ever made?

I think you don't need to use state-of-art node process to make an opamp, a battery-charging controller or a 8-bit microcontroller, and I guess the vast majority of chips we use are those things, not CPUs and GPUs, and it's reasonable to keep some old production lines and operate them.

As with any infrastructure, once a fab is built you keep it alive as long as it's cost-effective.

You could shrink the die, but what package will you put it in?

They do have some in smaller packages too, e.g. [1] that uses a PLCC-44 package, so ~16.7mm per side instead of ~5.2cm x ~1.5cm. The package above is that big because it's pin-compatible going back to the original 1975 version, and mostly drop-in compatible (barring some issues such as different levels of support for undocumented opcodes).

But of course even a PLCC-44 package is big compared to that die.

[1] https://eu.mouser.com/ProductDetail/Western-Design-Center-WD...

And that's kind of my point. If most 6502s are needed as legacy drop-ins, then there's no reason to shrink the die if you're just going to weld it into a massive DIP package.

Yes, I agree with you; sorry if that wasn't clear - absolutely don't think they'd gain much from shrinking it further. Anyone who cares about shrinking it down further would probably gain even more by licensing the core and embedding it together with other functionality anyway.

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