Storage in Streaming Media: Advanced Solid State Storage SSDs Meet Performance and Reliability DemandsSeptember 29, 2009 12:24 pm | by Gary Drossel, Western Digital | Comments
The rapid adoption of streaming media in embedded applications has been largely driven by decreasing bandwidth costs. In 2005, it cost approximately $.89 per gigabyte (GB) delivered for up to 49,000 GB (47.8 terabytes) of bandwidth. Today, a major content provider could pay a meager $.05 per GB delivered for 500 terabytes of bandwidth.
From hearing aids to Positron Emission Tomography (PET) imaging equipment, medical devices are increasingly impacting (and hopefully improving) our quality of life. Because we now rely on medical devices so heavily and because the devices’ software is so critical to their operation, software fault management and the ability to reduce faults throughout the development lifecycle have become hot-button issues.
Write-intensive applications require a mix of controller, storage media, and solid state storage management algorithms to achieve optimal endurance and lifespan, while read-intensive applications just go for the lowest cost per gigabyte. A key design metric for long product lifespan requires an understanding of the concept of write amplification and its crushing affects resulting in SSD failure when overlooked.
In Crossing the Chasm, Geoffrey A. Moore introduced the Technology Adoption Lifecycle. This curve highlights a chasm that exists between visionaries who are early adopters of technology and pragmatists who wait for proven technologies and products. For technologies to “cross the chasm” one key component are products with defined product specifications and system deployment guidelines.
The input signal is v1; the first five harmonic-distortion products are v2 through v6; and the ADC electronic noise is vn. The reciprocal of THD + Noise, the signal-to-noise-and-distortion ratio, or SINAD, is usually expressed in dB. If SINAD is substituted for the signal-to-quantizing-noise ratio, we can define an effective number of bits that a converter would have if its signal-to-quantizing-noise ratio were the same as its SINAD.
As applications engineers, we are constantly bombarded with a variety of questions about driving high-speed analog-to-digital converters (ADCs) with differential inputs. Indeed, selecting the right ADC driver and configuration can be challenging. To make the design of robust ADC circuits somewhat easier, we’ve compiled a set of common “road hazards” and solutions.
Wireless power interoperability marked an important milestone with the 31 July 2009 release of 0.95 specifications of Qi, the Wireless Power Consortium’s “WPC” international standard in wireless power. This interoperability means that all Qi power receivers can be powered and charged with all Qi transmitters.
You can find brushless-DC motors in appliances, medical instruments, and industrial equipment because they offer advantages over their brushed-DC-motor siblings. But before you can use a brushless-DC (BLDC) motor you need to understand how it works.
Editor's note No matter how good the tech, if it addresses an industrial or other demanding environment application, it better be able to deal with its surroundings without operational compromise.
As consumers clamor for smaller, sleeker and cheaper products, the pressure for embedded designers to find space and cost effective flash memory is higher than ever. Thankfully, serial flash memory devices provide the solution. Serial flash is a small, low-power NOR flash memory that uses SPI (Serial Peripheral Interface) bus, sometimes called “four wire” serial bus, for sequential data access.
Field-Programmable Gate Arrays (FPGA) are the most flexible and capable devices available to interface to a large variety of system devices such as memories, data acquisition (ADC/DAC), image sensors, displays, and so on. Often, the goal is to interface these system devices to a software infrastructure running on a workstation platform
As new laser devices become available, their complexity is met with increasingly sophisticated electronics that allow continuous refinement of precision. As optical systems mature, new processes and procedures are made possible. These include: lasers in medical diagnostic and treatment equipment (e.g. Optical Coherence Tomography (OCT)), increased sensitivity for environmental monitoring equipment
Designers of portable electronic devices have a variety of choices on types of chemistries, charger topologies and charge management solutions. Selecting the most suitable solution should be a simple task, but in most cases, it is a more complicated process. The designer needs to reach an optimal balance between performance, cost, form factor and other key requirements.
Supercapacitors are finding their way into an increasing number of applications for short-term energy storage. One such application is a power ride-through circuit, in which a backup energy source cuts in and powers the load when main power supply fails for a short time. This type of application has been dominated by batteries in the past
Recent advances in IGBT technology have given motor drive designers more options to consider for system development. Different specification conventions of various vendors complicate the design process further. Conventionally, system efficiency has been equated directly with VCEON. This metric is important for calculating the conduction losses of an IGBT but leaves out switching losses completely.