News and New Products

LeCroy's Eye Doctor for serial-data-bus analyzers focuses on eye patterns

By Margery Conner, Technical Editor -- EDN, 2/8/2007

With serial-bus speeds in the gigahertz range, designers of chips and boards that communicate with and over these buses often incorporate equalizers at the bus interface. Equalizers, essentially digital filters tuned for a particular bus’ speed and loading, can introduce their own noise into the system, requiring specialized equipment to track a problem, deciphering whether the bus, the receiver, or the board is the culprit? Enter the serial-data analyzer, essentially a DSO (digital storage oscilloscope) just for high-speed-bus analysis and troubleshooting. These analyzers display data in the form of eye patterns. LeCroy has introduced the Eye Doctor, a cosimulation system for its serial-data analyzers that allows you to capture gigahertz signals, explore equalization schemes, capture and compare waveforms, and model output signals of simulated interconnects and transmission designs.

Eye Doctor includes Virtual Probing, which enhances the accuracy of measurements on distorted waveforms. Virtual Probing can simulate any signals within the system using a single measured waveform. Its Processing Web Editor connects the equalizer and the Virtual Probing elements in an intuitive signal-flow-diagram layout. You can use Virtual Probing to de-embed probe and fixture responses from measurements to improve the accuracy of signal-integrity measurements. Eye Doctor also incorporates equalized-receiver emulation, which simulates embedded waveforms as if you were able to probe: It reveals the signal as a real receiver would see it at the detector, a feature that probes lack. Equalized-receiver emulation includes FFE (feed-forward equalization) and DFE (decision-feedback equalization), as well as clock recovery and a variable-decision threshold.

The Eye Doctor is now standard on all newly shipped LeCroy SDA6000A, SDA6020, SDA9000, SDA11000, and SDA18000 models. It is also standard on the WaveExpert series SDA100G. Current SDA users can install Eye Doctor on their SDA units with a retrofit kit. The SDA family has a price range of $34,500 to $128,000.