InnoGrit's Inexpensive SSD Controller Enables 7 GBps Reads

InnoGrit has introduced its first controller designed for performance-mainstream SSDs that combine high performance and relatively low cost. The Rainier QX SSD controller is a cheaper version of the company's flagship IG5236 'Rainier' controller that still features a PCIe 4.0 x4 interface, fewer NAND channels, but supports ultra-high NAND interface speeds. As a result, drives based on the Rainier QX promise to provide performance on par with today's best SSDs — up to 7 GB/s read speeds. 

InnoGrit's IG5221 'RainierQX' shares a lot of similarities with its bigger brother: it supports the NVMe 1.4 feature set, it is made using a 12 nm fabrication process and it probably has the same cores and same LDPC-based ECC algorithms. Unlike its bigger relative, the IG5221 'Rainier QX' has only four NAND channels with 8 CE per channel, which greatly simplifies its internal architecture, shrinks die size, lowers power consumption (down to 2.5W peak), and reduces the cost.  

Officially, the IG5221 supports NAND memory with ONFI 4.1 and Toggle 2.0/3.0/4.0/5.0 interfaces with speeds of up to 1,600 MT/s (up from 1200 MT/s in case of the IG5236), which is good enough for today. Meanwhile, InnoGrit told ComputerBase.de that the controller in facts supports NAND interface speeds of up to 2400 MT/s. A quad-channel SSD controller supporting a 2,400 MT/s interface can provide similar sequential read/write performance as an octa-channel controller that supports a 1200 MT/s interface.  

In this particular case, the IG5221 could enable drives featuring a capacity of up to 8TB with an up to 7 GB/s sequential read speed and an up to 6 GB/s sequential write speed. As for random performance, InnoGrit notes up to 800K random read IOPS as well as up to 600K random write IOPS.  

There is a caveat though. At present, there are no 3D NAND devices that support a 2,400 MT/s interface. Samsung's upcoming 7th Generation V-NAND and Kioxia's/Western Digital's BICS6 3D NAND are expected to support a 2,000 MT/s interface and as soon as these new types of memory gets qualified for SSDs (sometimes in the second half of 2022), drive makers may introduce relatively inexpensive products featuring a PCIe 4.0 x4 interface as well as leading-edge performance. 

Meanwhile, the InnoGrit IG5221 controller is currently sampling with select manufacturers, so the first SSDs powered by the chip will arrive to the market in the coming quarters. 

In addition, the InnoGrit IG5200-series family includes the IG5220 'RainierQ' controller for cheap SSDs. This one still belongs to the Rainier family, but it has four NAND channels with 4CE targets and therefore is meant for SSDs of up to 4TB. It is unclear whether the IG5220 actually supports a 2,400 MT/s interface, but officially the controller is designed for drives rated for an up to 5.1 GB/s read and up to 5 GB/s write speed.