QPHY-56G-PAM4

• Performs automated transmitter testing for 56 Gb/s (28 Gbaud) PAM4 interfaces
• Includes measurements for:
  • Eye diagrams
  • Eye widths and heights
  • Linearity (RLM and eye linearity)
  • Signal to noise and distortion ratio (SNDR)
  • Transition time
  • Linear fit pulse peak
  • PAM4 Jitter measurements: UUGJ, UBHPJ, EOJ
• Use Virtual Probe technology to de-embed test fixtures, emulate reference channels, and simulate compliance boards
• Includes a simple utility for selecting the optimum peaking value for the
  CEI 56G reference receiver CTLE
• QualiPHY report generation creates comprehensive reports with all pertinent test information

QPHY-56G-PAM4 makes the process of testing PAM4 devices quick and easy. The process is simple: select the standard variant to test, follow the simple onscreen instructions to connect your device, and click “start”. QPHY-56G-PAM4 automatically acquires the signal and performs the appropriate measurements on the relevant sections of the waveform. When a problem is detected, use the power of the serial data analysis tools to help find the root cause of excessive jitter or eye diagram failures.

While jitter measurements have become an established part of virtually all high-speed serial transmitter testing, PAM4-based signaling technologies require a new approach to jitter analysis. QPHY-56G-PAM4 extracts the Uncorrelated Jitter (UJ) distribution from the acquired signal waveform for each of the upper, middle, and lower eyes. From there, it calculates the jitter parameters required by the standard: Uncorrelated Unbounded Gaussian Jitter (UUGJ), Uncorrelated Unbounded High-Probability Jitter (UBHPJ) and Even-Odd Jitter (EOJ).

Some PAM4 standards require the oscilloscope to implement a reference receiver with a variable level of CTLE peaking. Selecting the optimal CTLE peaking value for the specific signal under test is crucial to obtaining the best results. QPHY-PAM4-56G includes a fast, simple utility test to determine the optimal CTLE peaking value for use in subsequent tests.

Several PAM4-based standards require the use of compliance boards. While physical compliance boardsmay be used, QPHY-56G-PAM4 includes the ability to emulate the behavior of an ideal compliance board via Virtual Probing technology, and even includes the required S-parameter files in many cases. In the case where “far-end” measurements are needed, the required reference channel model is included, and inserted automatically into the virtual signal path.

QualiPHY is designed to reduce the time, effort and specialized knowledge needed to perform compliance testing on high-speed serial buses.

• Guides the user through each test setup
• Performs each measurement in accordance with the relevant test procedure
• Compares each measured value with the applicable specification limits
• Fully documents all results
• QualiPHY helps the user perform testing the right way—every time!