PARIS – To do FD-SOI or not to do FD-SOI? NXP Semiconductors’ announcement this week at Embedded World in Nuremberg might finally put an end to this Shakespearean quandary, although there remain players in the chip industry unprepared to face the answer.
NXP launched what the company claims to be the lowest power general-purpose applications processors – dubbed i.MX 7ULP – yet developed for IoT applications.
According to NXP, the i.MX 7ULP design delivers a deep-sleep suspended power consumption of 15 uW or less, 17 times better than its previous low-power i.MX 7 devices. The dynamic power efficiency is improved by 50 percent in the real-time domain.
As previously reported, NXP has been working on microprocessor designs based on fully depleted silicon on insulator (FD-SOI) technology for a while.
The significance of this week’s announcement, however, is that NXP’s senior executive has unveiled a sweeping plan to broadly migrate design and production of general-purpose processors and microcontrollers from CMOS nodes to the FD-SOI process.
In a phone interview with EE Times, Geoff Lees, general manager and senior vice president of microcontrollers, security and connectivity, told us NXP has gained full confidence in the low power, high efficiency and scalability FD-SOI technology can deliver. With FD-SOI, Lees said, “We can now target a variety of family of processors from a single [FD-SOI] process node.”
The microprocessor product lines already transitioning to FD-SOI technology include NXP’s i.MX 7ULP family and the i.MX 8X family for automotive applications. Lees also noted that NXP is “seeing strong interest” in MCU-level products that are also based in this ultra-low power 28FD-SOI technology node. NXP, however, has not finalized launch timeframe with the lead customers or for broad-market introduction.
Not included in the migration plan is the very high-end i.MX 8, designed for advanced graphics and higher performance. The i.MX 8M family – mid-range processors for set-tops and OTT boxes -- would have been a good candidate for FD-SOI, said Lees, but it didn’t migrate because volume orders came before Samsung’s 28nm FD-SOI line was fully qualified.
How it all started
As Lees tells the story, NXP got a call about two years ago from Samsung. The i.MX team was then designing a third-generation processor using Samsung’s 28nm high-k metal gate process. The report from Samsung was that the foundry was seeing “dramatic improvements” in power, performance and efficiency in its FD-SOI process technology.
NXP and Samsung embarked on the development at that time. Samsung’s 28FD-SOI process was fully qualified for manufacture in the spring of 2016, and i.MX 7ULP first silicon arrived in fall of 2016.
The i.MX 7ULP applications processor family is currently sampling to select customers. Broader availability of pre-production samples is scheduled in the third quarter of 2017, according to NXP.
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