Toshiba has announced eight members of a new family of SLC NAND flash memory products. The devices feature an improved speed of 133 MHZ, as compared to the previous generation’s 104 MHz. Significantly, there is also a new command for loading data for programming in 4-bit (QSPI) mode.
Image from Toshiba Memory
What Is SLC NAND Flash?
SLC stands for "single-level cell", where a "cell" is a unit of memory storage for flash memory. SLC NAND Flash can store one bit of memory. This is contrasted with multi-level cell (MLC) NAND Flash which can store multiple bits.
Because of this higher data density, MLC flash has the advantage of lower cost per bits of storage. Based just on this information, it may seem counterintuitive for Toshiba Memory to pursue SLC NAND at this juncture. The key lies, as ever in engineering, in the context.
SLC, compared to MLC, boasts a greater data transfer rate. It's notable, too, that MLC is more error-prone (as SLC has a lower RBER or raw bit error rate), so error checking must be employed. Another MLC drawback is that it requires more power than SLC. Hence, SLC is attractive to designers who are working with applications that require faster data transfer rates.
High-Speed Transfer Rate Applications
Toshiba asserts that the new family of devices will be suitable for a wide range of applications that require higher data transfer rates. They expect these applications to include both consumer products (such as printers, wearables, and flat-screen TVs) and industrial products (such as robotics).
SLC NAND vs NOR Memory
NOR flash memory has long been a mainstay in embedded applications for both consumer and industrial devices. However, in today’s embedded devices, especially for IoT and communications applications, larger memory densities are needed. The extreme levels of miniaturization require fast, large-capacity flash memory in packages that take up the least possible board space.
Additionally, the trend is away from high-pin-count parallel address and data buses towards lower-pin-count serial interfaces. This makes an alternative to NOR even more important.
As per Brian Kumagai, Director of Business Development for Toshiba Memory America, Inc., Toshiba is clear that they "remain committed to supporting SLC" even as MLC finds utility. He added that this new family of devices provides "an excellent NOR flash alternative" and cites the higher density and lower costs of NAND solutions.
Members of Toshiba’s New NAND Flash Memory Product Family
Toshiba's new serial interface NAND family consists of eight products featuring power supply voltages of 2.70 to 3.60V and 1.70 to 1.95V. They communicate via the popular SPI (serial peripheral interface) bus. And, according to Toshiba, the addition of an 8-Gb device brings improved NAND density to what they've termed a "second-generation" products.
Each is available in a 3.3V option or a 1.8V option.
- 1Gb → TC58CVG0S3HRAIJ
- 2Gb → TC58CVG1S3HRAIJ
- 4Gb → TC58CVG2S0HRAIJ
- 8Gb → TH58CVG3S0HRAIJ
- 133MHz operating frequency
- Program / Read x4 mode
- High-speed sequential read function
- ECC Function (ON/OFF, bit flip count report)
- Data protection function (able to protect specific blocks)
- Parameter Page Function (able to output detailed information on the device)
The units will be available in 8-pin WSON (Very-Very thin Small Outline No Lead Package) packages taking up a scant 6 mm by 8 mm of board space. All of them will also be capable of operating between -40 °C and +85 °C.
NAND Memory Around the Industry
NAND memory is a booming business. Below are some other devices that are relevant to this Toshiba announcement.
- Samsung offers a series of SLC NAND devices with I/O speeds of 40 Mbps. Density ranges from 1 Gb to 16 Gb.
- Cypress’ series of SLC NAND products also span densities ranging from 1 Gb to 16 Gb. These units are AEC-Q100 qualified.
- Winbond's W25NO4KV Serial NAND Flash memory features 4 Gb density and an I/O speed of 104 MHz. The company also offers 2 Gb, 1 Gb, and 512 Mb versions.
What memory demands do you typically encounter in your job? Share your experiences in the comments below.