1.0 - SATA-IO

Tektronix, Inc.Test RX-01 - Pair Differential ImpedancePurpose: To verify that the Pair Differential Impedance of the PUT’s receiver is within the conformance limits.References:[1] SATA Standard, 7.2.1, Table 23 – Receiver Specifications[2] Ibid, 7.2.2.4.1[3] Ibid, 7.4.22[4] SATA unified test document, 2.13.1Resource Requirements:See Appendix A.See Appendix C for measurement accuracy specifications.Last Template Modification: April 10, 2006 (Version 1.0)Discussion:Reference [1] specifies the Transmitted Signal conformance limits for SATA devices. This specificationincludes conformance limits for the RX Pair Differential Impedance. Reference [2] provides the definition of thisterm for the purposes of SATA testing. Reference [3] defines the measurement requirements for this test.Test Setup:1. Matched length SMA cables have to be connected to the TDS/CSA8200 sampling oscilloscope; eachpair of the transmitter and receiver to one sampling module.2. The TDR signal amplitude should be less than 300mV peak-to-peak. This can be achieved byintroducing 6dB attenuators in the measurement path, this will provide approximately 125mV peak-topeak(single ended) TDR signal amplitude3. Each sampling module of the oscilloscope needs to be deskewed for acquisition using external sourcebefore connecting the fixtures. There is no need to deskew between the modules since themeasurements are done for the pairs within the modules. The sources deskew has to be performed inodd mode (source steps are of opposite polarity). The step signals should arrive at the PUT at the sametime. Both, acquisition and TDR deskew are to be performed at the SMA reference plane.4. Set 4000 acquisition points and 1ns/div in “Horizontal” menu and 300 averages in the “Acquisition”menu of TDS8200. Set math to a difference for TDR signals for each module, and filter this waveformto 40ps (10-90%) rise time.5. Power up the product under test (PUT) and complete a full OOB sequence.Comment: Is this a requirement? Justdo not recall this number. True for all Rxtests.Test Procedure:1. This procedure should be applied to the worst case port (in a multi-port system/host) as determinedthrough the worst case port identification MOI.2. Acquire the differential open reference using IConnect “Acquisition” tool.3. Connect the PUT and acquire TDRdd.4. Filter open reference and TDRdd waveforms to 135ps (10-90%) rise time.5. Use Z-line tool of IConnect to compute impedance profile. Set Zo equal to 100 Ohm and press on“Compute.” The resulting waveform will be displayed in the time domain viewer.6. Enable IConnect’s cursors by right-clicking the computed Z-waveforms and selecting “CursorReadout” option. Using the cursors measure the impedance value at a point 2 ns past the bottom of thelast major capacitive excursion (i.e. dip) that is known to be inside the ASIC device (Figure 4.1).7. Record the results.SATA Rx/Tx MOI Revision 1.1 ver 1.027