On May 13, 1:23*pm, Mike Harrison <m...@whitewing.co.uk> wrote:
> I'm looking at a possible application and trying to figure the relative costs of FPGA/CPLD versus
> MCU.
> I can do it with a microcontroller, but the only MCUs with the hardware Ineed (TFT LCD controller)
> tend to come with lots of other stuff (ethernet, large flash, USB etc.) which I don't need.
>
> As it can be hard to get 'real' prices of FPGAs without talking to all the distis etc. I *wonder if
> anyone can suggest parts to look at .
>
> Rough reqiurement is :
>
> Cheapest in 100x qtys for total solution inc. config and power supply ( from 3.3v supply), below
> about GBP5(US$7.5)
> Not BGA
> Readly available : ex-stock or sensible leadtimes (2 weeks)
> A couple of RAM blocks, around 1K byte each
> about 60 IOs, all 3.3v
> 30MHz clock
> Logic equivalent to around 100 CPLD macrocells
> Free or low cost (<$500) design software
>
> The Xilinx S3A/AN-50 is the cheapest I've found so far, but is a a bit over-specced.
> CPLDs seem to get expensive above 72 cells and don't tend to have RAM

the IC you need is always the one that doesnt exist

S3-50AN prices do go below 4$ but not at 100x qty.
in 100x qty, it proabably more than your target price 7.5 (depend how
good you deal..)

Xilinx disties say: leadtime 12 weeks, call for order
Digikey has 4 pcs in stock

if you can deal with 2 KB RAM, then lattice EC1 is 6.1$ online price
available in stock, need spi flash, but it still cheap total price

but here XC3S50A would be better at about same price

Lattice XP3 is too expensive with online pricing.. $10, stock YES,
this is the IC that needs NO Externals, no flash, no LDO, just 3.3V !

Actel A3P060, is cheap, but again 2K RAM only

all the above have free tools
Altera doesnt seem to have devices that come to your desired price
range

hm.. call lattice disti, say you would like XP3-VQ100, but your BOM
limit is 7.5$ see what they say !!

if price doesnt come down, place xc3s50a-vq100 order on digikey, to
secure your devices before those are gone too (disties have no stock.
leadt=12w)

Antti