MANHASSET, N.Y. Although speed and resolution have been the traditional factors engineers used to select data converters, specifying the appropriate converter hinges just as much on what application the part is used in, according to John Hussey of Analog Devices Inc.
In an interview with EE Times editors here, Hussey, Vice President of High Speed Conversion Products at Analog (Wilmington, Mass.) said the sheer variety of applications converters are used—consumer, automotive, industrial, medical, communications—dictate that closer attention be paid to cost, power requirements, and performance specs other than speed and resolution. These factors are in turn driving future product development, according to Hussey.
"We're trying to focus more attention on applications and what implications there are for customers," he said.
Hussey ran through a gamut of applications and discussed the key customer requirements for each. For instance, while ongoing cost reduction and the support for both legacy and new systems would be crucial for selecting converters used in set-top boxes, instrumentation applications would emphasize performance parameters such as high-speed transient signal capture and low noise and distortion, Hussey noted in a presentation.
Although most data converter makers, including ADI, have been steadily improving converter performance, engineers still face must negotiate a host of tradeoffs in selecting parts, according to Hussey.
As an example, Hussey said, "Higher sampling rates raise converter power and cost. Finding the optimal sampling rate is a tradeoff."
Power consumption is also becoming a critical factor in data converter selection, not only for portable products but non-portable products as well. "The customer wants to minimize the number of components and pack as much density as possible, without sacrificing thermal performance," Hussey said.
On the cost issue, Hussey said newer generation data converters offered essentially higher value than their predecessors, by eliminating added costs such as calibration.