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... How the growing popularity of distributed power architecture is impacting the ATE industry.
By Jim PenningtonAn Engineer or Manager need only browse current electronic periodicals to see the trend toward using DC/DC Converters in Distributed Power Architectures. These new high performance devices are also providing cost effective alternatives in custom configured power systems. Marketing studies have shown that some industries use more DC/DC Converters then AC/DC power supplies. The development of higher performance converters using new tSMPS echnologies, and the more stringent regulatory controls on AC line disturbances are major factors in establishing this trend for system designers. As with any new trend in technology, the implementation does not come without hurdles. Both manufacturers and users will have to solve a new set of problems to capitalize on the price and performance benefits of the DC/DC Converter.
For the experienced AC/DC power supply manufacturer, the new DC/DC concept presents these unique problems:
The requirement for miniaturization, low cost and high volume production make significant demands on manufacturing and product engineering. To many manufacturers, entering this market mandates the development of new facilities and production philosophies.
Component and hybrid manufacturers experience a different set of problems. Although adapted to the cost, volume and size issues, they are not well equipped for the testing technology requirements of these miniaturized SMPS.
The new DPA concept allows designers to more closely match the supply to their power requirements. But, the implementation requires a more detailed analysis of the power needs.
The power requirements for each PCB in the system must be uniquely specified. In addition, both the engineering and manufacturing disciplines must be prepared for processing the greater quantity of power supplies needed to have each PCB individually powered.
Since a major benefit of DC/DC is higher performance, this aspect must be verified. For this reason the test specifications of a DC/DC converter are typically more stringent. Examples of unconventional testing requirements for AC/DC power supplies are:
The higher performance characteristics of DC/DC converters also make standard testing more critical and difficult. For example, the need exists for verifying tight static and dynamic load regulation and high-resolution measurements at lower power.
The Output Dynamic Response (Regulation) is one example of how a typical test requirement for AC/DC and DC/DC power supplies differs. For an AC/DC power supply, it is only necessary to determine its response to a fast load change. For DC/DC power supplies the requirement also includes assessing the response to a fast line voltage change (Dynamic Line Regulations).
The DC/DC power
supply performance characteristic provides a much faster recovery
response (See Figure 1).
Because of this faster response, better measurement capability
in the testing instrumentation is required. Because the device
specifications include the same response characteristics to an
input line step, the testing scenario also requires
instrumentation for producing this step.
To meet the need for high volume and low cost, the use of ATE is essential. When selecting an ATE for this application, the critical areas to consider are:
An ATE technology that simply emulates a manual test station is no longer adequate. The ATE must meet the challenges of achieving an applications specific design on a versatile platform.
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10.18.2007