Honored ContributorWe have been using the ST Micro M25P16 as EPCS device for 3V3 designs. Is there a 2V5 equivalent flash chip or alternative? Thanks.
The only relevant info I have found is Altera AN 523: Cyclone III Devices Configuration Interface Guidelines with EPCS Devices
Honored ContributorYou can try Winbond W25X16AL. It should be compatible according to datasheet, but I didn't try.
Honored ContributorThanks, but the Winbond W25X16AL is NRFND and I couldn't even get samples.
The Numonyx M25PX16 works at 3V3, but it is apparently too slow at 2V5.Honored ContributorApparently, there's no market for 2.5 V serial flash devices, otherwise the leading manufacturers surely would service it. So if you want to operate an FPGA with 2.5V VCCIO only, you have to provide an additional non-standard 2.7 - 3.0 V serial flash supply. I guess, that future serial flash will be rather using 1.8V, like some Atmel AT25DFxx types.
Honored ContributorHow about the m25px16 (http://www.numonyx.com/documents/datasheets/m25px16.pdf)? I haven't actually tried this part with an Altera FPGA or looked at the data sheet very carefully, but it appears to support 75 MHz operation with a supply of 2.7 - 3.6V.
Honored ContributorPX devices are said to support 50 MHz down to 2.3 V, but they are not fully compatible to EPCS respectively M25Pnn devices, e.g. missing the electronic signature expected by the Quartus programmer. There may be ways to use it as AS configuaration memory though. I have no urgent need for 2.5V AS devices now, however. I simply stay with 3.3V operation for part of the IO banks.
P.S.: As Altera is permanently emphasizing the problems of 3.3V VCCIO with 65 nm devices, they should be more motivated to find a suitable solution for 2.5V AS configuration, I think.
