48V system has achieved great results, Vicor leads the new trend of data center power supply
““There is some misalignment between power demand and infrastructure today. The computing power of data centers, electric vehicles, etc. has grown significantly in the past few years, and with it comes a huge demand for power consumption, but the power transmission bus also They all stay on the 12V standard created in the past few years, and the upgrade to 48V system will become an important solution to meet the terminal needs.” A few days ago, Vicor Marketing Manager Meng Lingchong told the media when he attended the OCP conference. Last, Vicor, as the only supplier of board-level power modules/chips, discussed the 48V DC power supply system for data centers.
“There is some misalignment between power demand and infrastructure today. The computing power of data centers, electric vehicles, etc. has grown significantly in the past few years, and with it comes a huge demand for power consumption, but the power transmission bus also They all stay on the 12V standard created in the past few years, and the upgrade to 48V system will become an important solution to meet the terminal needs.” A few days ago, Vicor Marketing Manager Meng Lingchong told the media when he attended the OCP conference. Last, Vicor, as the only supplier of board-level power modules/chips, discussed the 48V DC power supply system for data centers.
Will power density and efficiency continue to grow?
With the advent and development of MOSFET technology, power conversion efficiency has greatly improved over the past three decades. Since the 80PLUS standard came into effect in 2007, the highest half-load efficiency requirement has reached 96% from gold to platinum and now titanium.
The efficiency and density of the power supply are strictly positively correlated. The higher the efficiency, the less heat dissipation. Therefore, a smaller volume, less power loss and a cheaper and simpler heat dissipation system can be realized, promoting the development of green and energy-saving information industry.
According to the product roadmap given by Vicor, between 2012 and 2019, the power density has been increased from 0.8 kW/cubic inch to 10 kW/cubic inch, and the point-of-load current density has increased from 0.8A to 2A. From a longer-term point of view, between 1984 and 2021, the power density has increased by as much as 500 times.
However, as the performance of MOSFETs is approaching its limits, power supply manufacturers are experimenting with a variety of innovations to meet the ever-increasing demands of power, efficiency and density. Including the use of wide bandgap devices such as GaN, SiC, newer topological junctions, etc., but Vicor has so far insisted on traditional silicon. Phil Davies, the company’s vice president of sales and marketing, once said in an interview: “I am often asked about the company’s When will GaN technology be adopted, but we don’t need them. Because low voltage MOSFETs are lower cost, higher quality factor, and we have achieved 800V input with a unique topology. So we have not needed to use expensive , GaN without extensive verification.”
On the one hand, Vicor continues to strive for excellence in product upgrades, and on the other hand, it provides system-level innovations around the 48V system, so as to more fully meet the upgrade of today’s advanced systems.
In any case, just as Moore’s Law is still advancing steadily despite its difficulties, power technology continues to use various methods to improve to meet the development of Moore’s Law.
Vicor’s 48V solution for big data centers
Almost all the power consumed by big data centers is converted from alternating current. Data centers generally have a complex set of current transmission paths, from AC to DC, and then further converted to power components such as memory, peripherals, processors, and more.
With the surge in the amount of data such as videos and pictures, data centers can no longer rely solely on CPUs, but have evolved into heterogeneous processing including GPUs, FPGAs, and AI processors. At the same time, the power consumption of processors using advanced processes is getting higher and higher, the core voltage is getting lower and lower, and the current is getting higher and higher. According to the formula of P=I²R, the loss on the power bus will increase. This is also an important reason why companies including OCP members Google, Facebook and other companies have upgraded the internal power bus to 48V.
Calculations given by Vicor show that if the entire system were switched to 48V, the efficiency would increase by 30%.
In the future, the core voltage of the processor will continue to decrease, and the current will increase rapidly
According to the characteristics of the current market, Vicor has launched three solutions including AC/DC, 12V/48V bridging and point-of-load. The company’s engineer Yang Zhou gave specific interpretations.
Addressing the last inch of power
First of all, for the point of load, Vicor provides a variety of solutions, including factorial power architecture, power-on-package lateral power supply (LPD), and power-on-package vertical power supply (VPD) technologies.
The factorial power supply architecture decomposes the power supply into dedicated regulation and voltage transformation functions. These two functions can be individually optimized and deployed to provide a high-density, high-efficiency solution. This solution is different from the traditional 12V multiphase solution, which mainly relies on a parallel array of switching regulators and inductors. This traditional solution is aimed at high power applications. The more regulators in parallel, the larger the overall size and the larger the processor. The farther the current travels. All of these add more losses to the system.
“After separating the two parts, the second stage does not need to design complex voltage regulation functions, and can realize a smaller and thinner fixed-ratio converter, which is more suitable for the compact space requirements around the CPU.” Yang Zhou said.
The horizontal power supply of the co-packaged power supply refers to the fractional second-level power supply module, which can be directly arranged close to the processor or even directly on the processor substrate, which can not only minimize the loss of the wiring harness, but also reduce the power required processor substrate BGA pins. Yang Zhou said: “Traditionally, the converter needs an Inductor for power supply, and the inductor cannot be too close to the CPU due to electromagnetic interference, which makes the last inch still have a large loss, especially when the current exceeds 1000A in the future. The LPD solution is It can solve the power supply problem of the last inch.” At present, LPD has been widely used in OCP accelerator module (OAM) cards and customized AI accelerator cards. According to the data provided by Davies, “In the application of 48V AI system, Vicor occupies 85% of the current market share. % market share.”
According to public information, domestic and foreign companies including NVIDIA, Intel, Cambrian, Tianshu Zhixin, and Google have all adopted Vicor’s solution. (The yellow strip in the picture below is Vicor’s power module)
Tianshu Zhixin’s PCIe accelerator card
Cambrian OAM Accelerator Card
NVIDIA accelerator card solution, including CPU core power supply module, HBM power supply module and peripheral power supply module
The VPD solution is a power supply solution that is closer to the CPU. Cerebras, for example, uses a Wafer Level Engine (WSE) to combine 84 processing units into a single processor, which can significantly reduce the propagation delays associated with traditional socketed single-signal chip architectures. However, the power of the WSE is as high as 15kW, and the area of the chip is too large, and the traditional power supply scheme cannot supply power to each unit at the same time. Therefore, Cerebras cooperated with Vicor to implement the VPD scheme, placing the power converter under the substrate, facing the position of the processor power IO, realizing the highest density power system.
Schematic diagram of LPD and VPD
Yang Zhou emphasized that Vicor provides many product portfolios, including integrated first- and second-level factorized power modules, as well as discrete solutions, and has achieved Pin 2 Pin compatibility of second-level modules, which is convenient for customers to adapt to the actual needs of the processor. Power consumption can adjust the module at any time.
Addresses bidirectional bridging from 12V to 48V
48V has many advantages, but at present, more than 90% of the traditional data center architecture is still powered by 12V, but accelerator cards, OCP accelerator modules, AI servers, etc. have been upgraded to 48V systems.
In order to realize the mixed solution of 12V and 48V, Vicor has introduced a bidirectional conversion solution from 12V to 48V. The scheme can automatically realize bidirectional conversion from 12V to 48V without any modification to the periphery, and achieves a conversion efficiency of over 98%. Not only does it require minimal external components, but it can also be easily paralleled for higher power levels. Vicor’s bridging solution gives customers greater flexibility to take full advantage of the new generation of AI cards as they navigate the transition to 48V power distribution. The recent emergence of bidirectional 48V/12V converters adds an extra layer of flexibility to cloud data center providers: as the infrastructure evolves, it can support either or both standards.
Davis previously said on the conference call: “Intel and AMD are using their CPUs in 48V data centers, where bridge chips will have huge demand, and the total market capacity will reach $500 million in five years, but compared to For Intel and AMD in hyperscale data center applications, AI still dominates the demand for bridging chips.”
12V to 48V bidirectional converter can be widely used in modules including SXM, OAM and HGX2
Solve the conversion of high voltage DC/DC and AC/DC
The power supply market for rack-mounted servers is also being challenged by a surge in power density. “Before 2015, the power of rack-mounted servers did not increase significantly, but after that, with the surge in power, there was an explosive increase in the power density of the rack. In 2020, the power of a rack may reach more than 200kW, according to the previous The calculation of the power density may require dozens of times the space, which brings great challenges to the power supply system.”
“The traditional power density improvement based on silver box (Silver Box) is too slow, and Vicor wants to break this tradition.” Yang Zhou said. Vicor provides two solutions for primary power supply, one is a high-voltage DC power module, which supports 400V/800V to 48V. The other is an AC to DC module, which is only the size of an iPad (92 mm × 80 mm × 7.5 mm), but can achieve 5kW power output and supports parallel connection. Due to its small size, it can be placed flexibly, including on the sides of the rack, the back, and even in liquid-cooled power boxes. In addition, Yang Zhou also said that the data center is still using traditional 220V power supply, but in order to achieve higher power density, it should turn to a three-phase 380V power supply system.
AC/DC converters can be flexibly arranged in various scenarios
More than ten years ago, Vicor began to develop and promote the 48V system, and has invested hundreds of millions of dollars. Today, remarkable results have been achieved. “During the development of 48V, in addition to clear data centers, we have seen applications including automotive, industrial, robotics, drones, rail transit, ATE equipment, and LEDs all beginning to get involved in 48V applications.” Meng Lingchong said.
According to Vicor’s latest 2Q21 financial report, the revenue of the Advanced Products product line, including 48V, has accounted for 43% of the company’s total business revenue, and this business revenue has increased by 20% month-on-month, which is why Vicor’s 2nd quarter revenue Overall revenue grew 7.4% sequentially to $95.4 million.
The long-term goal of Vicor is that the revenue of Advanced Products products will account for 80%, and the proportion of traditional brick power supply business will shrink to 20%. “In 2026, Advanced Products’ target market capacity will reach the level of 20 billion US dollars.” Davis said in the earnings conference.
It is for this reason that Vicor is expanding a new factory, adding 8,500 square feet of area, which is expected to meet the annual output value of 750 million US dollars. In addition, Vicor is also looking for opportunities to set up a new factory, which will eventually achieve an annual output value of 1.5 billion US dollars.
Chen Xinjun, sales director of Vicor China, head of data center and supercomputing, said: “Vicor is a company that pursues the ultimate. In order to achieve small and beautiful products, we continue to improve packaging, materials, and control technology to achieve higher efficiency and power. Density. At the same time, we are simplifying and standardizing power applications so that AI companies can focus more on the performance of the chip itself.”
“The world is changing rapidly, and as we begin to move from niche traditional markets such as military, aerospace and defense to rapidly growing emerging markets such as automotive and data centers, so are our competitors who have gone from Traditional power suppliers became more semiconductor companies,” Davis said. “We also have to make some changes.”
At the 2021 shareholder meeting, Vicor proposed a new five-tier growth strategy, including existing customers, new customers, high-growth markets, innovative products and technologies, and a clearer brand message, most of which, All will revolve around the 48V architecture.