DDR Test Solutions

Automatic separation of Read and Write bursts eliminates the time-consuming process of manual burst identification and simplifies the analysis of DDR systems. Bursts can be separated based on DQ-DQS skew or based on the command bus when used in conjunction with the HDA125. The HDA125 additionally enables a unique "bus view", tabulating the Command Bus activity and placing color-coded overlays and annotations on top of the physical layer waveform in an intuitive manner.

Any DQ, DQS or command/address signal can be tested against a standard or a custom defined mask, with up to 10 eye diagrams viewed simultaneously. Enabling mask failure indicators will automatically identify and locate the specific UI where any mask violation occurred. Built-in measurements such as eye height, eye width, and eye opening are critical to gaining a quantitative understanding of the system performance. With simultaneous eye measurements it is easy to compare performance across multiple testing views.

With a toolbox of parameters specific to DDR it is simple to quickly configure insightful measurements for validation, characterization, and debug. Up to 12 configurable measurements can be displayed and analyzed simultaneously across all active measurement views. For each measurement, advanced statistics such as min, max, mean, and number of measurement instances can be displayed and easily located with the searchable zoom feature.

Basic debugging and validation of embedded DDR interfaces typically involves analysis of the analog properties of the clock, data (DQ) and strobe(DQS) signals but when validation tasks become more complex and problems require deeper insight, the ability to trigger on, acquire and visualize the state of the DDR command bus is invaluable. The HDA125 brings command bus acquisition to Teledyne LeCroy’s already comprehensive toolset, providing the ultimate in memory bus analysis capability.

The HDA125 enables the unique “bus view” feature of the DDR Debug software option, which brings Teledyne LeCroy’s advanced bus analysis feature set to bear on DDR analysis. View bus activity in tabular form, and move time-correlated views to a desired event with the touch of a button. Search for specific events and bus states within the acquired record. Intuitive color overlays and annotations make it easy to identify areas of interest in the acquired analog waveforms.

The ability to trigger on specific states of the command bus becomes an invaluable tool for quick understanding of DDR signal quality. The HDA125’s logic triggering combines with the DDR Debug toolkit's intuitive setup and intelligent software cross-triggering to provide the ultimate DDR triggering system. Persistence maps of read and write bursts provide an easy and fast means of identifying subtle signal-quality problems for further investigation.