The M8040A from Keysight Technologies is a highly integrated 64Gbaud bit error ratio tester (BERT) that makes it easier for engineers in validation labs and R&D to perform physical layer characterisation of receivers for emerging 400G data centre interfaces.
R&D and validation labs that need to characterise high-speed receivers are facing new test challenges, such as tighter timing margins, channel loss, non-linearity, level interference and crosstalk effects. Test efficiency and accuracy are essential, and that’s where the M8040A shines, according to Keysight.
The M8040A is designed for receiver (input) testing of many popular interconnect standards based on PAM-4 and NRZ data formats up to 64Gbaud – corresponding to 128Gb/s per channel – including the latest revisions of the IEEE 802.3bs and OIF CEI-56G implementation agreements, which define PAM-4 and NRZ interfaces for electrical chip-to-chip, chip-to-module, backplane connections and optical interfaces for up to 400Gb/s bandwidth.
“The M8040A is the most integrated receiver test solution for PAM-4 and NRZ signals,” stated Joachim Peerlings, vice president and general manager of Keysight’s networks and data centres solutions business. “With the new built-in equalisation, we continue to streamline our receiver test to help our customers bring their solutions to market faster. The M8040A enables R&D and test engineers to master the receiver test challenges for 400G data centre interconnects.”
Test set-up has been simplified. Engineers and designers can software select PAM-4 and NRZ formats in the user interface, eliminating the need for external combiners, cabling and de-skew to provide PAM-4 signals. For best signal quality, remote heads reduce the distance to the device under test.
Overcoming channel loss in electrical interfaces is a big challenge with higher symbol rates. Pre-distortion techniques such as de-emphasis are used in the transmitter in combination with equalisation in the receiver to help re-open closed eyes caused by inter-symbol interference. The built-in equaliser in the M8040A BERT recovers the signal accurately to enable repeatable results.
The pattern generator module provides built-in de-emphasis, jitter injection and an optional second channel. The analyser module provides true PAM-4 error analysis in real-time for long bit patterns, making it easier to check even low-bit error ratios and symbol error ratios with the required confidence.
The M8040A is the latest member of Keysight’s modular AXIe-based M8000 series of BER test systems, which are scalable and upgradable to support current and future needs.