Hi all,
I have a design which requires a small FPGA, and I'm struggling to find an appropriate device.
The logic requires 'a few hundred' logic cells, and includes an adder that needs to run at about 100 MHz.
My usual favourite 'go-to' device for this type of thing is the Altera Cyclone IV EP4CE6. It's the smallest device in the range, costs about £10 in modest quantity, and comes in a 144 pin QFP which works on a standard 4 layer PCB.
It's one of my all-time favourite components, but for this job it's overkill. What I really want is a device that's about 1/4 the size, both in terms of logic and I/O count, and (crucially) won't require microvias or other HDI just to fit it to the PCB. Something like a 32 or 48 pin QFN would be perfect, but the world seems much more keen on tiny little WLCSPs that are an absolute pain to handle unless you're already making something ultra-tiny.
It would be nice (though not absolutely essential) to use another SRAM based device that I can easily download from an MCU as part of the boot process. That eliminates a production step, and means upgrades are trivial as they're just baked into the main firmware.
Of course, it would need to be cheaper than the Cyclone IV too, otherwise there's no point swapping to a new family. I'm not constrained for board space, so the EQFP144 isn't strictly a problem as such... it's just going to have a lot of pins unconnected, which seems wasteful.
Any FPGA enthusiasts here have a favourite small, relatively recent, fast-ish device that they wouldn't mind sharing?