Chinese firm says its new algorithm greatly improves reliability of QLC flash memory

China's main control technology provider Maxio Tech recently announced the successful development of the 4K LDPC algorithm. This is the first time that domestic SSD control chip manufacturers have achieved continuous breakthroughs in this technology, which will greatly improve the reliability and service life of QLC flash memory.

When it comes to QLC flash memory, many SSD hard disk users have serious mistrust of its reliability.  The reliability of SSD hard drives is a system problem. In addition to flash memory, it is also related to the main control, or the role of the main control is greater, especially the error correction algorithm has a great influence.

At present, the error correction algorithm of flash memory has been completely changed from BCH to LDPC (Low Density Parity Check), which is more advanced but more complicated than BCH algorithm.  It brings a sharp rise in power consumption of the main control chip, which brings great hidden danger to the stability of the SSD system.

In addition, the complicated decoding process of LDPC, especially soft decoding, will take up a lot of flash data bandwidth.  This reduces the actual performance of SSD users, and also seriously deteriorates the data read and write latency, resulting in a very poor user experience.

In terms of error correction technology, Maxio Tech has its own Agile ECC technology, of which Agile ECC 2 is based on 2K LDPC, and now it is a breakthrough in 4K LDPC, and successfully implemented the third generation Agile ECC 3 flash signal processing technology based on 4K LDPC error correction  Development and verification.

Maxio Tech said that compared to 2K LDPC error correction technology, 4K LDPC error correction performance has been greatly improved whether it is hard decoding or soft decoding.  Under the same original bit error rate (RBER), the error correction failure probability (UFER) of 4K LDPC can be reduced by at least two orders of magnitude relative to 2K LDPC.

In other words, under the same error correction failure probability (UFER) requirements, 4K LDPC can tolerate a higher raw bit error rate (RBER) of flash memory particles, which can greatly extend the service life of flash memory.

Maxio's Agile ECC3 technology introduces 4K LDPC, both hard decoding capability and soft decoding capability are greatly improved compared to 2K LDPC.

The improvement of the LDPC soft decoding capability guarantees the reliability of the flash memory data in the worst case and greatly prolongs the service life of the SSD.

The improvement of LDPC hard decoding capability can greatly reduce the probability of entering LDPC soft decoding, thereby avoiding the complicated LDPC soft decoding process and greatly improving the user's actual experience.

In addition, the LDPC code length from 2K to 4K will increase the complexity of the circuit implementation, theoretically it will increase the chip power consumption and cost.

However, Maxio Tech said that its 4K LDPC error correction technology uses a unique LDPC codec architecture and advanced dynamic power management technology, which greatly optimizes system power consumption and cost.

Maxio's third-generation Agile ECC technology based on 4K LDPC has undergone a series of technical innovations, which not only greatly improved the flash memory error correction capability of the main control chip, but also optimized the chip power consumption, bringing users excellent performance and ultra-low power consumption  Experience.