SanDisk has doubled the capacity of its solid state drive (SSD) with a G4 model lifting it to 256GB.
The previous G3 model offered 60 and 120GB with a 220MB/sec read speed and 120MB/sec write speed, and an endurance of 80TB written. Its shiny new G4 offers sequential read/write speeds of up to 220 and 160MB/sec and a 160TB written endurance rating, enough for a decade of normal use according to SanDisk.
A 32nm process is used along with multi-level cell (MLC) technology, but SanDisk doesn't say how many bits there are in each cell. It's recently introduced microSHDC cards with 3-bit MLC though. The drives come with Adaptive Flash Management (AFM) technology to speed performance and extend the working life. This includes the ExtremeFFS page-based algorithm.
There is also a thinner P4 model, succeeding the pSSD, and offering up to 128GB capacity. It's intended for tablet and ultra-thin notebook use, printers, set-top boxes and the like, with the G4 targeted as a drop-in replacement for notebook hard drives.
SanDisk says it has its own performance boosting technology, such as nCache: "a large non-volatile write cache technology that boosts burst random write performance to shorten boot times, help prevent 'stalling' and 'hiccups,' and increase system responsiveness. The... P4 offers burst random 4KB performance of up to 600 IOPS."
The P4 is available in various form factors that include a new ultra-small variant of the mSATA module, mSATA mini, with dimensions of 26.80 x 30.00 x 3.4 mm.
The 120GB G3 was announced in January, 2009. At this rate of development we might expect a 512GB G6 in July next year and a 1TB G6 by the end of 2012.
The G4 and P4 are being evaluated by OEMs. Mass production and OEM availability are expected in the third quarter of this year. ®