Column Control DTX

W2641A DisplayPort Test Point Access Adapter

Data Sheets

Emerging standards for consumer electronic devices and entertain­ment equipment provide for higher screen resolutions than ever before, which meets the market need for the highest computer monitor viewing quality possible. High screen resolutions neces­sitate higher link rates which place new demands on the source, sink and media such as cable or PC boards. This electrical signal environment makes measurement of physical layer parameters even more important and at the same time, more difficult. The Keysight Techologies W2641A DisplayPort test point access adapter pro­vides unrivaled convenience and performance.

DisplayPort standard

The evolution of the DisplayPort standard, sponsored by VESA, was driven by demand for higher-resolution and less-expensive computer dis­plays. Computer industry insiders have long believed that the industry would ultimately shift to all digital flat-panel displays, and DisplayPort is the digital transport interface stan­dard that finally promises to supplant the popular VGA CRT monitor. The low-profile DisplayPort connector is ideal for crowded back panels, moth­erboard designs able to drive multiple monitors, and portable equipment that offers uncompromised viewing. The DisplayPort connector has been designed to support the high Display­Port bit rates now and in the future. It is likely that DisplayPort will become the primary video interface for desktop and laptop personal computers, and it may ultimately be used in consumer electronics equipment such as DVD players.

The DisplayPort standard covers a wide range of screen resolutions and physical configurations. It outlines tests for the high-speed digital signals for source and sink testing, low-fre­quency control path (the AUX channel), link -layer and protocol verification such as HDCP (high bandwidth content protection) and media evaluation.

Test point access adapters

Test point access adapters (TPA) should be as transparent as possible to each measurement, connect to a wide range of test product form fac­tors, and have the flexibility to mea­sure several parameters. The W2641A TPAs have low loss, very good imped­ance characteristics and low intra-pair and inter-pair skew to provide the high signal fidelity connection required. These TPAs have been designed to conveniently connect to DisplayPort receptacles without obstructing ca­bles or presenting a footprint near the device under test greater than the Dis­playPort receptacle connector itself.W2641A DisplayPort test point access adapters provide the widest band­width and best performance on the market, thus enabling you to see the nuances of your source eye diagrams, printed circuit board and connector impedance profiles and evaluate your DisplayPort sink performance.

DisplayPort source testing

The DisplayPort Physical Layer Com­pliance Test Specification (CTS) covers source tests such as level verification, pre-emphasis level, skew, jitter, data eye, transition time and many other parameters. When you pair W2641A TPAs with Keysight Technologies’ Infiniium 90000 or 90000 X-Series oscilloscopes and the U7232A Display­Port compliance test software, you will have uncompromised accuracy and unrivaled simplicity in characterizing your source design. The TPA’s excellent performance enables you to clearly see nuances in the transmitted pattern and determine how to improve the perfor­mance of the source and channel. The U7232A DisplayPort compliance test software automates measurements of the multitude of parameter configura­tions possible in DisplayPort devices and provides you with an extensive report on how the devices have per­formed. The U7232A is designed for use in validation and compliance labs so you can use the full measurement suite before you submit your devices to a DisplayPort Authorized Test Center for certification to make sure you’ve taken care of problems in advance.

DisplayPort AUX channel testing

The DisplayPort specification includes a special channel, the AUX chan­nel, which is used to dynamically coordinate the link source and sink. The W2641A exposes this differential lane that operates at 1 Mbs with two connections available: one using the standard SMP connectors used in the high-speed lanes and another on a digital interface header. Also available on the digital interface header are power supply lines and the hot plug detect (HPD) line, which can also be probed for noise measurements, trig­gering, etc.

DisplayPort sink testing

The DisplayPort Physical Layer Com­pliance Test Specification stipulates a receiver tolerance test regimen where the digital data is transmitted with phase jitter having sinusoidal and random characteristics, as well as a calibrated channel degradation (called intersymbol interference, or ISI). The signal parameters, such as jitter quantity and level, vary accord­ing to the bit rate being tested. These signals can be injected to a Display­Port sink from Keysight sources such as the N4903A JBERT and the 81250 ParBERT through the W2641A.

For the calibration of the sink test set­up, a complementary receptacle test fixture is needed. This is available as a third party product BIT-DP-RTF-0001 from BitifEye Digital Test Solutions, (see www.bitifeye.com). The same product is needed for testing so-called tethered devices, i.e. devices such as monitors with DisplayPort ca­bles inseparably connected to them. To facilitate automated measurements and process control, the N5990A test automation software platform offers automated DisplayPort compliance and characterization tests.

DisplayPort device connection

The W2641A connects directly into a DisplayPort receptacle connec­tor such as found on graphic cards, motherboards and on PCs. The fixture was designed to reduce possibility of interference to other connectors and cable types. Even so, there are always connection configurations where inter­ference is seen or where perpendicular entry to the W2641A is inconvenient or impossible. To address some of these conditions, the W2641A DisplayPort Adapter fixture comes with highly flexible cables with constant imped­ance characteristics even when acutely bent. A diagram of such a test setup is shown below and the impedance difference is shown adjacent. It is clear that no degradation in measurement accuracy is seen.

Extra convenience in connection is afforded by the addition of the N5460A cables, which have a right angle SMP connection. These are phase matched to less than 2ps and have superior impedance and loss characteristics.

×

Please have a salesperson contact me.

*Indicates required field

Preferred method of communication? *Required Field
Preferred method of communication? Change email?
Preferred method of communication?

By clicking the button, you are providing Keysight with your personal data. See the Keysight Privacy Statement for information on how we use this data.

Thank you.

A sales representative will contact you soon.

Column Control DTX