Multiplexing ATE channels for production testing at 2.5 Gbps

We describe two versions of a multiplexing test system for multigigahertz devices. Our approach leverages test resources available in existing ATE, and achieves higher rates with added multiplexing logic. In the prototype, 32 high-speed differential-pair signals each support data at 2 Gbps to 2.5 Gbps. An updated system uses water cooling to better maintain the test electronics temperature. This system also has improved relays for better signal integrity, and better embedded calibration circuits to obtain stable operation at 2.5 Gbps. The production version is scalable to as many as 144 high-speed differential-pair signals. Integral to the design are embedded circuits that support automated, accurate timing calibration with 10-ps resolution.