Silicon Motion SM2322 USB 3.2 Gen 2x2 Native Controller: Extended QLC Support for 8 TB PSSDs

Silicon Motion's SM2320 native USB 3.2 Gen 2x2 controller for USB flash drives and portable SSDs has enjoyed great market success with a large number of design wins over the last few years. Silicon Motion proudly displayed a selection of products based on the SM2320 on the show floor at FMS 2024.

The SM2320 went into mass production in Q3 2021. Since then, the NAND flash market has seen considerable change. QLC is becoming more and more reliable and common, leading to the launch of high-capacity cost-effective 4 TB and 8 TB SSDs. Newer NAND generations with flash operating at higher speeds have also made an appearance.

The SM2320, fabricated in TSMC's 28nm node, supported four channels of NAND flash running at up to 800 MT/s. The new SM2322 uses the same process node and retains support for the same number of flash channels and chip enables (8 CEs per channel). However, the NAND can now operate at up to 1200 MT/s.

The SM2322 also improves the QLC support, thanks to the implementation of a better ECC scheme. While the SM2320 opted for a 2KB LDPC implementation, the SM2322 goes in for a 4KB LDPC solution. The use of a larger region enables extension of the NAND's useful life.

The SM2322 and SM2320 packages are similar in size, and Silicon Motion expects PSSD designs using the SM2320 to adopt the SM2322 with different NAND (higher capacity / speeds) using the same enclosure. Products based on the SM2322 are expected to appear in the market before the end of the year.