Electronic – What’s the catch with FRAM


After recently acquiring an MSP430 Launchpad I've been playing with various microcontroller projects. Unfortunately, the MSP430G2553 only has 512 bytes of RAM, so doing anything complex requires external storage.

After looking at SPI and I2C SRAM and EEPROM chips, I discovered FRAM.

It looks perfect. Available in large sizes (the one linked to above is a 2Mb part), low power, byte addressable and programmable, nonvolatile, no wear issues, no need to explicitly erase anything, and actually cheaper than serial SRAM (comparing against Microchip's parts).

In fact, it looks too perfect, and that makes me suspicious. If this stuff is so much better than serial SRAM and flash EEPROM, why isn't it everywhere? Should I stick with SRAM, or is FRAM a good choice for experimentation?

Best Answer

From what I can see, the (main) difference between it and SRAM is it's slower, and the difference between it and EEPROM is it's more expensive.
I'd say it's sort of "in between" both.

Being a pretty new technology, I'd expect the price to drop a fair bit over the next year or so providing it becomes popular enough. Even though it's not as fast as SRAM, the speed is not bad at all, and should suit many applications fine - I can see a 60ns access time option on Farnell (compared with a low of 3.4ns with SRAM)

This reminds me - I ordered some Ramtron F-RAM samples quite a while back, still not got round to trying them yet...