Switching Solutions for Multi-Lane BERT Testing
应用文章
Introduction
Many high-speed digital interfaces use multiple lanes to achieve the throughput requirements for their systems. With this brings challenges for validation and characterization because of connection requirements, including single-ended as well as differential testing and more lines than BERT (bit error rate tester) channels available. A Keysight Technologies, Inc. switching solution can resolve these challenges with high reliability at an affordable cost. This application note addresses the use of switching solutions, degradations that might be encountered, and the methods to overcome them.
The focus of this application note will be on the testing of optical transceivers. To test a 4-lane optical transceiver with a BERT, you must connect and test each lane one after the other, due to limited test ports. Figure 1 shows a typical setup for optical transceiver testing using a BERT. To test 4 lanes simultaneously, an investment in multiple sources and detectors would be required but this is not cost effective solution.