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Electronic design consultants, DE Technology use Altium Designer to design high speed video processing technology for Tecton Ltd, a major UK manufacturer of security recording systems

“The flexible and innovative features of Altium Designer helped us to create complex designs more quickly. These features have evolved with its ongoing development to offer us a state-of-the-art design environment”

- David Edwards, Managing Director, DE Technology

The Background

For the past fourteen years DE Technology has been designing high speed video processing for Tecton Ltd.

Tecton were one of the first companies to develop video multiplexers, which allowed more than one camera to be recorded on a time-lapse video recorder, establishing a strong customer base with their Kramplex product.

With the assistance of DE Technology, the Miniplex and Drax range of video multiplexers were developed, setting the benchmark for high speed multiplexing with up to seventeen cameras combined at 50 fields per second. Equipment such as this is still in use in many locations including Network Rail and the London Underground, alongside the newer product range of Darlex digital recorders. These use wavelet video compression and record onto disk drive arrays.

There are inevitable drawbacks with both the old and new technologies. VHS video tapes can be used continuously in a time-lapse recorder set to rewind before recording from the beginning once more. Good examples of this are seen in the appalling quality of images from small shops where the same tape has been reused for several years. Digital recording suffers no loss of quality and software can monitor disk performance and warn of impending hardware failures. However, following an incident, the recordings are treated as original evidence and are held by the police. Replacing video tapes is far cheaper than replacing disk drives.

Sadly, such systems can only assist in piecing together events afterwards and cannot prevent the crime from taking place. Tecton Miniplex images at Luton were released to the press in the aftermath of the July 7th bombs in London in 2005, along with images from Drax and Darlex systems on the Underground and from Kings Cross. Further images were released two weeks later following the aborted attacks, and several arrests were made as a result of identifications from the recorded images.

The Need

With the inevitable increase in both complexity and clock speed, signal integrity becomes a crucial issue. Intermittent errors caused by digital crosstalk or poorly defined clock edges are time consuming to track down if they are not identified until the prototype PCB phase. In addition, there are differential, impedance and length matching constraints to consider. The Solution DE Technology has been using Protel and Altium design tools since 1992 when they were chosen as a Windows based replacement for their DOS design tools. More recently, the high speed design rules have been found to be vital in the design of Tecton products. The ability to place PCB directives on the schematics to control autorouting and the subsequent analysis of signal integrity using IBIS models from the chip manufacturers reduces the risk when committing the design to production. These tools are proving indispensable in the design of the next generation of products.

At the other end of the spectrum, the flexibility of Altium Designer has also been put to good use in the design of layout sensitive analogue boards using manual routing. This has allowed, in the case of a photodiode amplifier, a 40dB improvement in sensitivity over the design it replaced.

About DE Technology

DE Technology was formed in 1990 as an electronic design consultancy. Since then, it has established a reputation in two particular diverse areas. As consultants to a UK subsidiary of a major US defence manufacturer, they have been involved in the design and implementation of low noise charge amplifiers for engine diagnostics and high sensitivity photodiode amplifiers for helicopter blade tracking systems. The design of very low noise analogue circuits contrasts with their other area of expertise; the design of high speed video processing for Tecton Ltd, a major UK manufacturer of security video recording systems.

References

Visit the DE Technology website

Premier EDA Solutions would like to express their thanks to David Edwards and DE Technology for all their help in producing this customer story.