FOCUS RESEARCH NEWS UC Berkeley scientists develop processor with inbuilt photonic I/O
Engineers at the University of California, Berkeley have fabricated a microprocessor with integrated photonic interconnects, a first according to the researchers. The 3 x 6mm chip contains two processor cores with 70 million transistors and 850 photonic components. The microprocessor was fabricated with mass production equipment, showing it can be scaled up easily.
‘This is a milestone. It’s the
first processor that can use light to communicate with the external world,’ said Vladimir Stojanovic, an associate professor of electrical engineering and computer sciences at UC Berkeley, who led the development of the chip. ‘No other processor has the photonic I/O in the chip.’
In demonstrating the chip, the engineers showed that it had a bandwidth density of 300 gigabits per second per square millimetre, about 10 to 50 times greater than packaged electrical-only microprocessors currently on the market.
‘This is the first time we’ve put a system together at such scale, and have it actually do something useful, like run a program,’ said UC Berkeley professor Krste Asanovic, who helped develop the free and open architecture called RISC-V (reduced instruction set computer). The photonic I/O on the chip is also energy efficient, using 1.3 picojoules per bit, equivalent to consuming 1.3W of power to transmit a terabit of data per second. In the experiments, the data was sent to a receiver 10 metres away and back. ‘The advantage with optical is that with the same amount of power, you can go a few centimetres, a few metres or a few kilometres,’ said study co-lead author Chen Sun, ‘For high-speed electrical links, one metre is about the limit before you need repeaters to regenerate the electrical signal,
www.electrooptics.com | @electrooptics FEBRUARY 2016 l ELECTRO OPTICS 13
and that quickly increases the amount of power needed. For an electrical signal to travel 1km, you’d need thousands of picojoules for each bit.’
One potential application of this technology is to make data centres
more energy efficient. According to the Natural Resources Defense Council, data centres consumed about 91 billion kilowatt-hours of electricity in 2013, about two per cent of the total electricity consumed in the United States.
The research has already spun off two startups this year with applications in data centres in mind. SiFive is commercialising the RISC-V processors, while Ayar Labs is focusing on photonic interconnects.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56