Keysight Technologies N4915A-014

The PCI Express 3.0 base specification defines the receiver test requirements for chipsets and ASICs. In difference to previous standards, the receiver test is now %22normative%22 (a %22must%22), and no longer informative (%22optional%22). When transmitting 8 GT/s over FR4 PC board material the signal distortions become significant. PCIe 3.0 compliant receivers have to tolerate a certain eye closure while ensuring the bit error ratio remains <10-12.

Agilent offers test equipment which provides repeatable and accurate receiver voltage stress and jitter tolerance testing. The setup includes J-BERT N4903B, the N4916B de-emphasis signal converter, N4915A-014 PCIe 3.0 calibration channels, 81150A/81160A pulse function generator as interference source, Infiniium 90000 X-Series oscilloscopes for stress calibration and N5990A test automation software.

The N5990A-101 test software for PCIe receivers automates the stress calibration procedure. This includes capturing signals with a real-time oscilloscope at an accessible test point (TP2) and constructing the eye opening as seen inside the receiver at TP2P (for reference see PCIe 3.0 base specification chapter 4.3.4.4.1; figure 4.71 ) by post-processing the package model, CTLE (continuous time linear equalizer), receiver's clock recovery, DFE (decision feedback equalizer) and limiting amplifier.

Besides the stress calibration, the N5990A-101 software provides automated receiver testing for all revisions of PCIe specifications. Users can pick the tests from the user interface, add margins if desired, get guidance for instrument cabling, and the software controls all connected test instruments used in the setup. Compliance and characterization tests are supported and test reports can be exported.

The N4915A-014 PCIe 3.0 calibration channels allow reproducing the worst-case channel conditions (PC-board traces in the real world) that a PCIe 3.0 compliant receiver will have to tolerate. A det<