10BASE-T1S Automotive Ethernet Compliance Test Solution

Fully automated compliance testing

The Tektronix 5-CMAUTOEN10/6-CMAUTOEN10 Automotive Ethernet (10Base-T1S Short Reach) automated compliance test solution is a fully automated compliance test application for the 10BASE-T1S (IEEE 802.3cg™) standard. Executing all the measurements manually is extremely time-consuming. The TekExpress Automotive Ethernet application provides an automation framework that enables you to execute all the measurements with minimal intervention, only when you need to change connections.

The physical layer compliance tests are defined to ensure interoperability between different designs and hardware vendors. The requirements to perform these tests have been expanded and now cover Automotive Ethernet 10BASE-T1S standards.

The test suite runs on 5 Series and 6 Series B MSOs, and lets you to take full advantage of the oscilloscope validation and debug capabilities in addition to compliance testing. The Tektronix Automotive Ethernet Solution provides greater confidence in design margins under real world conditions by ensuring that your designs pass the strict 10BASE-T1S compliance tests.

The 5-CMAUTOEN10/6-CMAUTOEN10 TekExpress Automotive Ethernet software allows for complete or selective testing of any of the transmitter electrical specifications. Tests are configured by following a step-by-step process. Software navigation follows a logical workflow for quick test setups, configurations, and review of test results. The software sets up the oscilloscope and automates the tests, guiding you to accurate and repeatable results.

Test setup configurations vary greatly in terms of connections to the device under test, probing, test fixtures, calibration, and use of the oscilloscope and signal generator. To help you to correctly set up for a measurement, the Automotive Ethernet software provides setup instructions for each test, with images and reference illustrations, to ensure the correct setup.

The application generates a comprehensive, date-stamped test report with pass/fail results, waveforms, and data plots.

The 5-CMAUTOEN10/6-CMAUTOEN10 TekExpress Automotive Ethernet compliance software requires a Tektronix 5 Series or 6 Series B MSOs with Option 5-WIN/6-WIN or SUP5-WIN/SUP6-WIN (Microsoft Windows 10). Since it operates as a Windows application, the software shares the oscilloscope display. For convenience, we recommend that you add an external monitor to display the compliance software and test reports separately from the oscilloscope screen.

Return loss measurement

The MDI return loss test determines the impedance mismatch between PHY and reference MDI Connector from the differential impedance specification of 100 Ω, which will affect hardware interoperability. Return Loss is a frequency domain measurement and generally requires an additional frequency domain test instrument to run the measurement. Using a patented technique, you can perform an MDI return loss measurement using oscilloscope and function generator. To learn more about return loss measurement using oscilloscope, please refer to Patent No US007271575B2.

Transmitter clock frequency and jitter measurements

Jitter tests quantify the timing variations of the edges of the signal, using specified test patterns. These jitter measurements include contributions from duty cycle distortion and baseline wander. The jitter peak-to-peak measurement is determined by the minimum and maximum values in the tails of the histogram. The DUT is set to test mode 1.

Droop measurement

The droop measurements are performed by determining the positive and negative waveform peak voltages. The DUT is set to test mode 2.

Power spectral density measurement

Power Spectral Density (PSD) is a frequency domain measurement that is often performed using a spectrum analyzer. The 5 Series and 6 Series B MSOs, with 12-bit analog-to-digital converters (ADC) and outstanding noise performance, provides accuracy similar to a spectrum analyzer. The spectrum of an input signal in test mode is computed using built-in oscilloscope math functions. The post-processing is done on the signal to determine the PSD. The computed PSD is then compared with the upper and lower masks as defined in the specification to arrive at the final result.

Limits

The 10BASE-T1S Automotive Ethernet can operate in point-to-point or multi-drop mode. In point-to-point connections, devices operate at 100 ohm impedance but in other cases devices operate at 50 ohm impedance. The IEEE specifies measurement limits for 100 ohm and 50 ohm impedances. The Tektronix 5-CMAUTOEN10/6-CMAUTOEN10 10BASE-T1S Automotive Ethernet compliance software allows you to configure limit depending upon the device configuration. The application can work in compliance mode, where limits are defined per compliance specifications, or in user defined mode, which allows you to edit the limits to perform characterization of the DUT.

Validation and debug

Validation and debugging are easily accomplished early in the design process and ahead of final compliance testing with the 5 Series and 6 Series B MSOs. The oscilloscopes' standard measurement set, along with the optional DJA (Advanced Jitter and Timing Analysis) software supports several key compliance tests including:

• Clock frequency

• Transmitter amplitude with histogram

• Full characterization of jitter performance including Time Interval Error (TIE)

• Histogram profiles

This type of early testing increases the likelihood of passing compliance tests, while allowing more complete characterization and determination of design margins. Master and slave jitter measurements can be particularly challenging given the tight compliance limits and the need to eliminate any possible sources of random or deterministic jitter.

Pass/fail reports

The 5-CMAUTOEN10/6-CMAUTOEN10 Automotive Ethernet (10Base-T1S Short Reach) automated compliance test application creates compliance test documentation quickly with a summary report in MHL or PDF format. The software automatically generates a report after test execution is complete, and includes Pass/Fail status to help you quickly analyze the test results. The report also includes test configuration details, waveform plots, oscilloscope screen shots, and margin analysis to provide more insights into your design.

6 Series B MSO Oscilloscope

With up to 10 GHz analog bandwidth, 50 GS/s sample rates, lowest noise and highest resolution, the 6 Series B MSO oscilloscope has the performance you need to capture waveforms with the best possible signal fidelity.

At the heart of the 6 Series B MSO oscilloscope are 12-bit analog-to digital converters (ADCs) that provide 16 times the vertical resolution of traditional 8-bit ADCs. This resolution, combined with an extremely low-noise front end, allows you capture small signal details even on relatively large signals.

Test fixtures and probing test points

Accurate and repeatable compliance testing requires access to the PHY transmitter output. The recommended approach is to use the Tektronix TF-XGbT Ethernet fixture. These fixtures can support all test setups while providing convenient test points for probing. If there is a provision to probe directly on DUT, user can perform compliance test without fixture.

Ordering information

Measurements and required hardware

Required hardware

Required software

Optional software

Recommended accessories

Additional accessories for Multidrop test