Agilent Technologies LXI manual Longevity, Flexibility, 1970 1980 1990 2000

5. Longevity

Figure 3 provides a compari- son of various interfaces over the past 30-plus years. Most noteworthy is the continuous improvement in LAN perfor- mance while maintaining backward compatibility, sug- gesting that it will continue as a dominant force in the computer industry for a long time to come.

Extensions designed into the LXI Standard ensure that it will meet the foreseeable needs of the test and measurement industry, a critical requirement of the automotive electron- ics industry that supports an active aftermarket and long product lifetimes.

6. Flexibility

Cardcage-based solutions limit the optimal instrumentation placement in a test rack. For example, system creators will find it useful to put switching in one low-cost subsystem and stimulus/measurement instru- ments in another, simplifying service and avoiding use of high-cost, high-performance backplanes to control slow relays (often the case in PXI or VXI cardcages).

LXI instrumentation enables a better approach: A modular switch/measure unit equipped with an internal digital multi- meter (DMM) and a selection of switching cards offers a low-cost method of creating a dedicated switching subsystem. The use of LAN also makes it possible to place the LXI-based subsystem farther from the host PC and closer to the unit under test.

Few cardcage-based power supplies meet the current requirements of many automo- tive electronic modules and require external power supplies based on different architectures. Agilent has updated existing designs to be LXI compliant, housing them in compact, rack- friendly enclosures. Examples include the Agilent N5700 series of high-power supplies and the Agilent N6700 series of modular supplies (Figure 4).

Figure 4. Some LXI-compliant power supplies have size, power and functionality advan- tages over GPIB and PXI alternatives.

GPIB

VXI

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LXI

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Web

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Rapid IO

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Figure 3. LAN has evolved – and maintained backward compatibility – while other interfaces have come and gone.

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