星空女人频道: 2013-10-13

2013年10月19日星期六

Business IPextreme, Mentor combine to sell IP

2013/10/18

Xena_SemiconductorCompanies_Diagram IPextreme, the leading IP broker, has joined with Mentor Graphics to sell IPextreme’s IP.

Products available for licensing include automotive IP including CAN and Flexray cores; debug IP, including IEEE 1149.7 compact JTAG; 8/16/32-bit microcontrollers and complete sub-systems; and the Xena enterprise level IP management software platform.

Warren Savage, CEO of IPextreme, sees the deal as a catalyst for expansion at IPextreme comparing the deal to Starbucks co-locating in a Safeway store.

“We’re offering all our IP plus Xena, ” says Savage. The Mentor sales force can sell the IPextreme IP and customers will sign a license agreement with IPextreme and issue a purchase order to Mentor.

The IP is delivered via a Xena server.

“We see significant opportunities for deeper collaboration on the EDA side, as well as roadmap alignments on new IP titles that our mutual customers are demanding in their next generation SoCs,” says Savage.

IPextreme customers, like Infineon, welcomed the move as a way for more customers to get access to Infineon’s IP blocks.

IPextreme is dubbed the iTunes store of the IP world. The Xena IP allows IP developers, to put the IP they’ve developed in the Xena store for users to license or buy.

A buyer or licensee can use a search engine designed by IPextreme, to search across all the IP in the Xena store to find what they’re looking for.

A variant allows big companies to share IP across their internal divisions. Savage quotes an exec for an IP company who told him: “We often get customers where one division buys an IP licence for the entire company but doesn’t tell the other divisions. We just sell them another licence.”

“In big companies the IP function was traditionally done by the CAD department,” explains Savage, “but in the last decade CAD departments have been gutted along with other non-revenue-producing units.” So a big company can get a virtual CAD department via Xena.

This is very often very necessary if customers are to understand their needs. Savage quotes an IP manager at a large IP company saying they’d recently bought a UART from IPextreme only to find they had 32 UART designs in-house

IPextreme’s service becomes more and more necessary as complexity soars. The average number of gates per chip, now 120,000, is going to 240,000 in 2017 and the average number of IP blocks per chip is going from 100 now to 180 in 2017.

“Xena” says Savage, “detangles your IP problem.”

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General How to characterise FETs quickly

2013/10/18

As fundamental components of many devices and electronic instruments, field effect transistors (FETs) are important semiconductor devices.

A FET is a majority charge-carrier device in which the current-carrying capability is varied by an applied electric field. It has three main terminals: the gate, the drain, and the source.  A voltage applied to the gate terminal (VG) controls the current that flows from the source (IS) to the drain (ID) terminals.

There are many types of FETs, including the mosfet (metal-oxide-semiconductor), mesfet (metal-semiconductor), JFET (junction), organic FET, graphene nano-ribbon (GNRFET) and carbon nanotube (CNTFET). These FETs differ in the design of their channels.  FETs are used in a variety of applications including as amplifiers, memory devices, switches, logic devices, and sensors.

Characterising their current-voltage (I-V) parameters is crucial to ensuring they meet specifications and work properly in their intended applications. These I-V tests may include gate leakage, breakdown voltage, threshold voltage, transfer characteristics, drain current and on-resistance. FET testing often involves programming and synchronising several instruments, including multiple sensitive ammeters and voltage sources, which can be tedious and time consuming.

Although a turnkey semiconductor characterisation system solves the integration problem, systems of this type typically cost tens of thousands of dollars.  A third approach involves using an instrument called a source measure unit (SMU) that can accurately source and measure both current and voltage.

The number of SMUs required in the test usually depends on the number of FET terminals that must be biased and/or measured.

This article outlines how to make faster I-V measurements on FETs using SMU instruments, a growing number of which include software tools that simplify device characterisation.  For example, Keithley’s series 2600B family of one- and two-channel SMUs have current resolution to 0.1fA and can be current limited to prevent damage to the device.

Using an SMU for FET testing

A FET’s I-V characteristics can be used to extract many device parameters, to study the effects of fabrication techniques and process variations, and to determine the quality of the contacts.

Figure 1 illustrates a DC I-V test configuration for a mosfet using a two-channel SMU (CH1 and CH2). Here, the Force HI terminal of SMU CH1 is connected to the gate of the MOSFET and the Force HI terminal of SMU CH2 is connected to the drain.

FET test circuit

The source terminal of the mosfet is connected to the Force LO terminals of both SMU channels or to a third SMU channel if it is necessary to source and measure from all three terminals of the mosfet.

Once the device is set up and connected to the SMU, the control software, often an embedded software tool, must be configured to automate the measurements.

After connecting the instrument to any computer with an Ethernet cable, entering the IP address of the SMU into the URL line of any web browser will open the instrument’s web page. From that page, the user can launch the embedded software and configure the desired test or tests, which can often be saved and recalled for future use.

One I-V test commonly performed on a mosfet is the drain family of curves (VDS-ID). With this test, SMU CH1 steps the gate voltage (VG) while SMU CH2 sweeps the drain voltage (VD) and measures the resulting drain current (ID).

Once the two SMU channels are configured to perform the test, the data can be generated and plotted on the screen in real time.  Once exported to a .csv file, this I-V data can be imported into a spreadsheet for further analysis or displayed in table view.

Another common I-V FET test this same configuration supports is Drain current (ID) as a function of gate voltage (VG). For this test, the gate voltage is swept and the resulting drain current is measured at a constant drain voltage.

Drain current plot

Figure 2 shows the results of an ID-VG curve at a constant drain voltage.  However, in this case, the generated data was exported to a file and plotted on a semi-log graph. This test can be easily reconfigured to step the drain voltage as the gate voltage is swept. The ID-VG data shows the many decades of drain current that the SMU measured, from 1E-12 to 1E-2A

This test can be easily reconfigured to step the drain voltage as the gate voltage is swept. The ID-VG data shows the many decades of drain current that the SMU measured, from 1E-12 to 1E-2 amps.  When measuring low current, it’s crucial to employ low level measurement techniques, such as shielding and guarding, to prevent errors.

Shielding usually implies the use of a metallic enclosure to prevent electrostatic interference from affecting a high impedance circuit.

Guarding implies the use of an added low impedance conductor, maintained at the same potential as the high impedance circuit, which reduces the leakage current in the test circuit.  A guard doesn’t necessarily provide shielding.

Mary Anne Tupta, senior staff applications engineer, Keithley Instruments

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Business Analogue ASPs down; units up

2013/10/18

IC Insights IC forecast The analogue IC ASP is forecast to decline 11% in 2013, but analogue IC units are expected to grow 9%, states IC Insights.

Increased competition for design wins in medical/health applications and in portable consumer/communication systems helped drive down the total analogue ASP, but
there was a very strong 14% upturn in analogue IC unit shipments in 2Q13.

IC Insights believes this was due to general inventory rebuilding and but also from growth of portable mobile devices, which have been a catalyst for power management analogue and consumer analogue IC unit growth.

This momentum carried into 3Q13 and well, and was forecast to result in a 9% increase in analogue unit growth. Historically, sales and unit shipments of ICs slow down in the fourth quarter of the year as the buildup to the holiday buying season ends.

For the year, analogue unit shipments are forecast to exceed 100-billion devices for the first time in history and the overall revenue growth is expected to be 1%.

The analogue IC market has struggled to post meaningful sales revenue growth over the past five years.

Contributing to the ASP decline is that many analogue manufacturers have moved production to 200mm wafers (300mm wafers, in some cases), which has helped cut manufacturing costs per die.

Some of the strongest analogue IC unit growth in the first half of 2013 came from power management devices, which help extend useful battery life and operation of battery-powered, portable and mobile systems.

In the application-specific segment, very strong unit growth for communications and Industrial analog devices offset significant declines in consumer and computer analogue shipments in the first half of the year.

IC Insights believes rising sales of personal and portable medical/health electronics contributed to the uptick in Industrial analogue shipments.

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Business Faster charging from Power Integrations

2013/10/18

Charger Physical Interface IC for Quick Charge 2.0 – Typical Application Schematic

Today, Power Integrations introduced the first reference design for a Qualcomm Quick Charge 2.0-enabled charger power supply.

Launched earlier this year, the Quick Charge 2.0 protocol enables users to charge mobile devices up to 75% faster than when using conventional USB charging technology.

Power Integrations has developed the ChiPhy family of AC-DC wall-charger interface ICs which, when combined with the company’s AC-DC switcher ICs, incorporates all of the necessary elements to add rapid charging functionality to AC-DC wall chargers.

The CHY100 IC detects commands from a Quick Charge 2.0-enabled device, and adjusts the output voltage of the AC-DC wall charger to deliver increased power to the device’s battery through a standard USB cable.

When plugged into a five-volt USB-powered device without Quick Charge 2.0 capability, CHY100 IC automatically disables the higher-voltage capability to ensure safe operation and backwards compatibility with older hardware.

An evaluation platform for ChiPhy ICs, DER-381 describes a CV/CC charger power supply capable of up to 24 W utilizing TOPSwitch-JX switcher and CHY100D interface ICs.

The PSU operates from universal input and provides selectable output voltages (5 V, 9 V, and 12 V) with a maximum constant current of 2 A. The TOPSwitch-JX IC maintains virtually constant efficiency across a very wide range of output voltages and current load conditions.

“DER-381 shows how a Quick Charge 2.0 charger power supply can be successfully implemented using Power Integrations’ switcher and interface ICs and simple optocoupler feedback,” says PI’s Peter Vaughan.

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2013年10月18日星期五

Researchers advance toward engineering 'wildly new genome'

Oct. 17, 2013 — In two parallel projects, researchers have created new genomes inside the bacterium E. coli in ways that test the limits of genetic reprogramming and open new possibilities for increasing flexibility, productivity and safety in biotechnology.

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In one project, researchers created a novel genome -- the first-ever entirely genomically recoded organism -- by replacing all 321 instances of a specific "genetic three-letter word," called a codon, throughout the organism's entire genome with a word of supposedly identical meaning. The researchers then reintroduced a reprogramed version of the original word (with a new meaning, a new amino acid) into the bacteria, expanding the bacterium's vocabulary and allowing it to produce proteins that do not normally occur in nature.

In the second project, the researchers removed every occurrence of 13 different codons across 42 separate E. coli genes, using a different organism for each gene, and replaced them with other codons of the same function. When they were done, 24 percent of the DNA across the 42 targeted genes had been changed, yet the proteins the genes produced remained identical to those produced by the original genes.

"The first project is saying that we can take one codon, completely remove it from the genome, then successfully reassign its function," said Marc Lajoie, a Harvard Medical School graduate student in the lab of George Church. "For the second project we asked, 'OK, we've changed this one codon, how many others can we change?'"

Of the 13 codons chosen for the project, all could be changed.

"That leaves open the possibility that we could potentially replace any or all of those 13 codons throughout the entire genome," Lajoie said.

The results of these two projects appear today in Science. The work was led by Church, Robert Winthrop Professor of Genetics at Harvard Medical School and founding core faculty member at the Wyss Institute for Biologically Inspired Engineering. Farren Isaacs, assistant professor of molecular, cellular, and developmental biology at Yale School of Medicine, is co-senior author on the first study.

Toward safer, more productive, more versatile biotech

Recoded genomes can confer protection against viruses -- which limit productivity in the biotech industry -- and help prevent the spread of potentially dangerous genetically engineered traits to wild organisms.

"In science we talk a lot about the 'what' and the 'how' of things, but in this case, the 'why' is very important," Church said, explaining how this project is part of an ongoing effort to improve the safety, productivity and flexibility of biotechnology.

"These results might also open a whole new chemical toolbox for biotech production," said Isaacs. "For example, adding durable polymers to a therapeutic molecule could allow it to function longer in the human bloodstream."

But to have such an impact, the researchers said, large swaths of the genome need to be changed all at once.

"If we make a few changes that make the microbe a little more resistant to a virus, the virus is going to compensate. It becomes a back and forth battle," Church said. "But if we take the microbe offline and make a whole bunch of changes, when we bring it back and show it to the virus, the virus is going to say 'I give up.' No amount of diversity in any reasonable natural virus population is going to be enough to compensate for this wildly new genome."

In the first study, with just a single codon removed, the genomically recoded organism showed increased resistance to viral infection. The same potential "wildly new genome" would make it impossible for engineered genes to escape into wild populations, Church said, because they would be incompatible with natural genomes. This could be of considerable benefit with strains engineered for drug or pesticide resistance, for example. What's more, incorporating rare, non-standard amino acids could ensure strains only survive in a laboratory environment.

Engineering and evolution

Since a single genetic flaw can spell death for an organism, the challenge of managing a series of hundreds of specific changes was daunting, the researchers said. In both projects, the researchers paid particular attention to developing a methodical approach to planning and implementing changes and troubleshooting the results.

"We wanted to develop the ability to efficiently build the desired genome and to very quickly identify any problems -- from design flaws or from undesired mutations -- and develop workarounds," Lajoie said.

The team relied on number oftechnologies developed in the Church lab and the Wyss Institute and with partners in academia and industry, including next-generation sequencing tools, DNA synthesis on a chip, and MAGE and CAGE genome editing tools. But one of the most important tools they used was the power of natural selection, the researchers added.

"When an engineering team designs a new cellphone, it's a huge investment of time and money. They really want that cell phone to work," Church said. "With E. coli we can make a few billion prototypes with many different genomes, and let the best strain win. That's the awesome power of evolution."

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Power AMS releases automotive cell balancing chip

2013/10/18

AS8506-Passive-Balancer-Board_f524

AS8506 evaluation board

AMS has joined the firms offering cell balancing chips for electric vehicle Li-ion stacks. Its AS8506 can operate in both passive and active modes, and has a built-in balancing algorithm, cell monitoring and communication.

Cell balancing allows the maximum capacity to be squeezed from a battery whose cells inevitable differ in capacity, particularly as they age.

Passive balancing is simple – current which would over-charge a cell is dissipated through a resistor.

Active balancing is less wasteful, transferring unwanted power to uncharged cells. It is more complex to implement, and suitable power-transfer methods are still being invented.

“The architecture developed by AMS has been implemented to perform distributed cell monitoring and balancing operations for stacked cell modules, including safe operating area checks and passive or active cell balancing,” said the firm, claiming: “It is ideal for all lithium-based cell chemistries, such as those found in hybrid and electric vehicles, as well as for EDLCs, also known as supercaps or ultracaps.”

Including a balancing algorithm is unusual. All other cell balancing chips Electronics Weekly has heard of so far require a separate microcontroller to implement this.

AS8506 external cell balancing circuits

“The new architecture can control balancing locally at the cells, enabling designers to implement a more streamlined cell management system that eliminates the host controller, complex software and vulnerable serial communication links normally used today. Both passive and active cell balancing is autonomous,” said AMS.

That said, the firm cannot be completely against remote control as it added: “Or it can support a microcontroller-based system via its serial peripheral interface.”

It argues that local balance control has access to all cell voltages simultaneously, whereas remote balancing requires the microcontroller to accumulate all cell data through a long serial link, and then re-time it to make decisions.

The firm’s architecture has far fewer components that Linear Tech’s recent LTC3300 – only one mosfet and one transformer per chip in active mode, compared with two mosfets and one transformer per cell.

However, the 8506 is unidirectional and less flexible. It can only take power from a fixed section of the stack and deliver it one cell at a time (see below). In the data sheet application notes it takes it from the whole stack and therefore needs a high-voltage mosfet. The 3300 can arbitrarily shift power to and from any cell or cells in a stack full time and needs only low-voltage mosfets.

The reason AMS’s chip needs so few external components is that internal 100mA power switches connect cells one at a time to a single external fly-back circuit for active balancing, or a single external resistor for passive balancing (see diagram below). Therefore, for any particular cell, balancing is pulsed rather than continuous.

In active mode, the fly-back PWM frequency (25-200kHz) and duty

-cycle are factory programmable and register

controllable. The external mosfet drive pin can also operate an opto-coupler for isolated drive.

Internal switches sequentially offer cells for balancing

“Cells which are below target will either cyclically receive charge packages from an isolated dc-dc converter or cells above target will cyclically be discharged by an external resistor through integrated switches in an autonomous way,” said AMS. “The device can be used for battery stacks of three up to seven cells [6-32V]. It can be chained to support battery packs of virtually any number of cells in a synchronised mode.”

It is worth noting that only passive balancing is possible with the over-the-counter chip. “Active balancing mode need to be enabled by factory setting. It is not available for the default ASSP,” said AMS.

On chip monitoring and balancing is through precision circuits, with pins reporting cell-voltage-within-limits and balance-ready, while cell voltages and temperatures (from two thermistors per chip) are sent to the outside world via an ADC and serial communication.

“An analogue circuit compares up to seven cell voltages against an internal or external reference with an accuracy of 1mV to support cell-balancing and cell-monitoring functions. Cell voltage measurements can also be digitised with an accuracy of 5mV and reported to a host controller,” said the firm.

For a seven cell ’24V’ stack, only one one chip is needed. Beyond this, multiple chip are chained along the battery with each chip passing communications to its immediate neighbours.

Target cell voltage and minimum and maximum cell voltage can be broadcast to all chained devices.

Application notes in the data sheet cover balancing for two-chip ’48V’ connection using 100V mosfets.

A stand-alone passive balancing evaluation kit for up to seven cells is available (pictured), as well as a more comprehensive active/passive balancer board.

Applications are also expected in electric motorcycles, scooters, bicycles, karts and power tools, as well as on or off-grid storage for solar or wind energy – solar street lights, for example.

It comes in a 6x6mm package.
More cell balancing
LT3300
TB9141
Electronics weekly cell-balancing blog (written pre-LT3300 was release)

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Gene regulation differences between humans, chimpanzees very complex

"We thought that we knew how to identify patterns of mRNA expression level differences between humans and chimpanzees that would be good candidates to be of functional importance," said Yoav Gilad, PhD, Professor of Human Genetics at the University of Chicago. "Now we see that even such mRNA patterns are not translated to the protein level. Which means that it is unlikely that they can affect a functional phenotypic difference."

For genes to be expressed, DNA must be transcribed into messenger RNA (mRNA), which then code for proteins, the biological building blocks and engines that drive cellular function. Although humans and chimpanzees share highly similar genomes, previous studies have shown that the species evolved major differences in mRNA expression levels. Many of these differences were thought to indicate areas of evolutionary divergence, thus pointing to genes important for human-specific traits.

To test this, Gilad, Jonathan Pritchard, PhD, currently at Stanford University, and their team, spearheaded by postdoctoral fellow Zia Khan, PhD, used high-resolution mass spectrometry to compare the expression levels of thousands of proteins with corresponding mRNA expression data in human and chimpanzee cell lines.

The team found 815 genes with differing mRNA expression levels but only 571 genes that differed in protein expression. In total, they identified an estimated 266 genes with mRNA differences that did not lead to changes in protein levels. They found similar results in rhesus macaque cell lines when compared to both chimpanzees and humans, confirming the trend.

"Some of these patterns of mRNA regulation have previously been thought of as evidence of natural selection for important genes in humans, but this can no longer be assumed," Gilad said.

The study raises questions over why mRNA expression levels differ between species if they do not necessarily cause protein differences. Although further study is needed, Gilad believes this study suggests that protein expression levels evolve under greater evolutionary constraint than mRNA levels, via a yet-uncharacterized compensation or buffering mechanism.

For now, research that uses mRNA expression levels as a measure of the functional importance of a gene requires reassessment, and not just in studies on evolution.

"We've gained insight into complex diseases by studying mRNA transcripts, but we also have a lot of gaping holes in our knowledge. Perhaps some of them are because of this disparity," Gilad said.

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Brain may flush out toxins during sleep

Oct. 17, 2013 — A good night's rest may literally clear the mind. Using mice, researchers showed for the first time that the space between brain cells may increase during sleep, allowing the brain to flush out toxins that build up during waking hours. These results suggest a new role for sleep in health and disease. The study was funded by the National Institute of Neurological Disorders and Stroke (NINDS), part of the NIH.

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"Sleep changes the cellular structure of the brain. It appears to be a completely different state," said Maiken Nedergaard, M.D., D.M.Sc., co-director of the Center for Translational Neuromedicine at the University of Rochester Medical Center in New York, and a leader of the study.

For centuries, scientists and philosophers have wondered why people sleep and how it affects the brain. Only recently have scientists shown that sleep is important for storing memories. In this study, Dr. Nedergaard and her colleagues unexpectedly found that sleep may be also be the period when the brain cleanses itself of toxic molecules.

Their results, published in Science, show that during sleep a plumbing system called the glymphatic system may open, letting fluid flow rapidly through the brain. Dr. Nedergaard's lab recently discovered the glymphatic system helps control the flow of cerebrospinal fluid (CSF), a clear liquid surrounding the brain and spinal cord.

"It's as if Dr. Nedergaard and her colleagues have uncovered a network of hidden caves and these exciting results highlight the potential importance of the network in normal brain function," said Roderick Corriveau, Ph.D., a program director at NINDS.

Initially the researchers studied the system by injecting dye into the CSF of mice and watching it flow through their brains while simultaneously monitoring electrical brain activity. The dye flowed rapidly when the mice were unconscious, either asleep or anesthetized. In contrast, the dye barely flowed when the same mice were awake.

"We were surprised by how little flow there was into the brain when the mice were awake," said Dr. Nedergaard. "It suggested that the space between brain cells changed greatly between conscious and unconscious states."

To test this idea, the researchers used electrodes inserted into the brain to directly measure the space between brain cells. They found that the space inside the brains increased by 60 percent when the mice were asleep or anesthetized.

"These are some dramatic changes in extracellular space," said Charles Nicholson, Ph.D., a professor at New York University's Langone Medical Center and an expert in measuring the dynamics of brain fluid flow and how it influences nerve cell communication.

Certain brain cells, called glia, control flow through the glymphatic system by shrinking or swelling. Noradrenaline is an arousing hormone that is also known to control cell volume. Similar to using anesthesia, treating awake mice with drugs that block noradrenaline induced unconsciousness and increased brain fluid flow and the space between cells, further supporting the link between the glymphatic system and consciousness.

Previous studies suggest that toxic molecules involved in neurodegenerative disorders accumulate in the space between brain cells. In this study, the researchers tested whether the glymphatic system controls this by injecting mice with labeled beta-amyloid, a protein associated with Alzheimer's disease, and measuring how long it lasted in their brains when they were asleep or awake. Beta-amyloid disappeared faster in mice brains when the mice were asleep, suggesting sleep normally clears toxic molecules from the brain.

"These results may have broad implications for multiple neurological disorders," said Jim Koenig, Ph.D., a program director at NINDS. "This means the cells regulating the glymphatic system may be new targets for treating a range of disorders."

The results may also highlight the importance of sleep.

"We need sleep. It cleans up the brain," said Dr. Nedergaard.

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Gravitational waves help us understand black-hole weight gain

A paper in today's issue of Science pits the front-running ideas about the growth of supermassive black holes against observational data -- a limit on the strength of gravitational waves, obtained with CSIRO's Parkes radio telescope in eastern Australia.

"This is the first time we've been able to use information about gravitational waves to study another aspect of the Universe -- the growth of massive black holes," co-author Dr Ramesh Bhat from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR) said.

"Black holes are almost impossible to observe directly, but armed with this powerful new tool we're in for some exciting times in astronomy. One model for how black holes grow has already been discounted, and now we're going to start looking at the others."

The study was jointly led by Dr Ryan Shannon, a Postdoctoral Fellow with CSIRO, and Mr Vikram Ravi, a PhD student co-supervised by the University of Melbourne and CSIRO.

Einstein predicted gravitational waves -- ripples in space-time, generated by massive bodies changing speed or direction, bodies like pairs of black holes orbiting each other.

When galaxies merge, their central black holes are doomed to meet. They first waltz together then enter a desperate embrace and merge.

"When the black holes get close to meeting they emit gravitational waves at just the frequency that we should be able to detect," Dr Bhat said.

Played out again and again across the Universe, such encounters create a background of gravitational waves, like the noise from a restless crowd.

Astronomers have been searching for gravitational waves with the Parkes radio telescope and a set of 20 small, spinning stars called pulsars.

Pulsars act as extremely precise clocks in space. The arrival time of their pulses on Earth are measured with exquisite precision, to within a tenth of a microsecond.

When the waves roll through an area of space-time, they temporarily swell or shrink the distances between objects in that region, altering the arrival time of the pulses on Earth.

The Parkes Pulsar Timing Array (PPTA), and an earlier collaboration between CSIRO and Swinburne University, together provide nearly 20 years worth of timing data. This isn't long enough to detect gravitational waves outright, but the team say they're now in the right ballpark.

"The PPTA results are showing us how low the background rate of gravitational waves is," said Dr Bhat.

"The strength of the gravitational wave background depends on how often supermassive black holes spiral together and merge, how massive they are, and how far away they are. So if the background is low, that puts a limit on one or more of those factors."

Armed with the PPTA data, the researchers tested four models of black-hole growth. They effectively ruled out black holes gaining mass only through mergers, but the other three models are still a possibility.

Dr Bhat also said the Curtin University-led Murchison Widefield Array (MWA) radio telescope will be used to support the PPTA project in the future.

"The MWA's large view of the sky can be exploited to observe many pulsars at once, adding valuable data to the PPTA project as well as collecting interesting information on pulsars and their properties," Dr Bhat said.

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Embedded Systems TIs safe car chip combines Cortex-A15 with C66x DSP

2013/10/16

Big_Little_Image(1) Texas Instruments unveiled in Baden-Baden, Germany an automotive system-on-chip (SoC) device for advanced driver assistance systems (ADAS).

With its TMS320C66x digital signal processor cores, the chip provides 2D and 3D surround view and rear collision warning and can also run a pedestrian/object detection algorithm developed for the front camera.

TI’s TDA2x also serves as a central processor for fused radar and camera sensor data, allowing more robust ADAS decision making.

There are ARM Cortex-A15 MPCore processors and dual Cortex-M4 cores along with video and graphics cores and peripherals.

Dubbed a Vision AccelerationPac, this is designed to run low to mid-level vision processing functions, offloading the DSP and ARM cores.

The Vision AccelerationPac contains one or more multiple Embedded Vision Engines (EVEs), comprised of an optimised vector coprocessor and a 32-bit programmable RISC core.

TI is offering royalty-free software libraries and framework to provide developers an optimised collection of vision and imaging functions.

The TDA2x is under development respecting the relevant requirements of ISO 26262 functional safety standard. Supporting safety documentation will be available to customers upon device PPAP and release.

The TDA2x is currently sampling and is intended for high-volume automotive manufacturers.

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