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Comment by f_devd | Hacker News Reader

I wish it was possible to do this without the crowd sourcing, I have a low-volume HDL project of just ~40 gates and 32 shift registers (+4*32 gates) which discrete is quite bulky, FPGAs are overkill and CPLD works but are often too small or unavailable.

Based on rumors maybe atomicsemi will provide this at some point.

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The smallest Lattice iCE40 are under $2 in volume, it may be "overkill" but also pretty tough to beat economically at low quantities. Especially keeping in mind one of the limitations of these MPW silicon runs is the parts you get are untested... reasonable in prototyping but an obstacle to scaling up to low volume production.

Dialog (nee Silego) Greenpak is a cheaper programmable option if you can find one that your design fits in. The design flow is a little more idiosyncratic.

Of course often the cheapest option these days for low-end digital logic requirements is to emulate your logic in a microcontroller, if you can get away with that speed wise. It might not feel very elegant but the economy of scale is tough to beat.

Personally it's analog and mixed signal design that I'd love to see cheap and easy custom silicon for... I've got a design with some DACs, analog switches, jellybean op amps, and a dozen-ish discrete transistors that would be really great to integrate and miniaturize, but it doesn't seem practical at ~10k volumes.

The transistors are the hard part to integrate here. From the manufacturing side, why waste the die space on your MCU production line when you can use a much older process to build transistors for pennies.

For mixed signal design in general, the Cypress PSoC 4 series is pretty good.

Renesas is also doing a lot of work in the low BOM cost configurable analog/digital space, with Greenpak and ForgeFPGA: https://www.renesas.com/tw/en/products/programmable-mixed-si... https://www.renesas.com/tw/en/products/programmable-mixed-si...

I did consider iCE40 (mainly due to the icestorm/yosys project) for our project at the time but they weren't available I believe, I will have to look into it again. Unfortunately a microcontroller was not really an option as the ones we generally use don't have a input FIFO buffer/peripheral fast enough (clocked 25Mbit/s) although there may be others that can, we didn't look further in to it as it seemed like a pretty expensive option given the simplicity of the circuit and the HDL that was already finished.

Raspberry Pi has microcontroller that may work for you (RP2040) it has programmable IO thingy that is quite impressive). Anyway regarding small FPGAs/CPLDs - i am passively keeping eye on small/inexpensive parts - and as far as I know it is not field abound with options (Cypress PSOC, LAttice iCE40, small CPLD from Altera(Intel)/Xilinx(AMD)). Just learned about GreenPAK (Dialog and now Renesas) and I am quite thrilled. Do not know how it could fly under my radar.

> The smallest Lattice iCE40 are under $2 in volume,

Those have got open-source tools, right? And they're relatively easy to work with, I guess.

What can you do with them? Like, how "big" a thing could I make? I've got a project for which I need a bunch of programmable 16-bit counters that'll pulse an output when they roll over zero. Could I make those in an iCE40? How many would fit?

"up to 7680 programmable logic cells", so at a very conservative estimate of one cell per bit of counter that's 480 counters. So you'll probably run out of I/O first.

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