SAS-2 6Gbps PHY Specification

Transcription

1 SAS-2 6Gbps PHY Speciication T10/07-063r2 Date: March 8, 2007 To: T10 Technical Committee From: Alvin Cox Subject: SAS-2 6Gbps PHY Electrical Speciication Abstract: The attached inormation deines the electrical requirements or 6 Gbps transmitter devices and receiver device. In addition, updates may include reerence transmitter and receiver device deinitions to provide a means o determining i a channel is compliant and a cable speciication section with requirements or 6Gbps usage. Editor notes are included as reminders or speciication development. Revisions will not include redlines. Revision History: r0: Initial posting that is very preliminary and nowhere near complete, provided as a starting point and a basis to leverage the inal PHY proposal rom rather than a PowerPoint ormat. r1: Updated emphasis measurement, changed SCD22 to SCD11 and corrected receiver common mode impedance value. r2: Updated emphasis measurement, changed SCD11 back to SCD22 and updated the igure or SCD22. Reerence proposals: SAS-2 Common Mode Generation Speciication [Witt, Bari] Proposed 6G SAS Phy Specs or EMI Reduction [Jenkins] Proposal or 6G SAS Phy Speciication [Jenkins] SAS-2 Reerence Transmitter and Receiver Speciication Proposal [Witt] SAS-2 Data Eyes vs. De-Emphasis [Witt] Roadmap to SAS-2 Physical Layer Speciication [Witt] Enhanced SFF-8470, SFF-8086 and SATA Cable at 6Gbps [Witt] Comparison o Equalization Schemes or 6Gbps SAS Channels [Caroselli] Towards a SAS-2 Physical Layer Speciication [Witt] SAS-2 Cable Reach Objective and Crosstalk [Witt] SAS-2 Channel Model Simulations [Witt] SAS-2 Adaptive Equalizer Physical Layer Feasibility [Witt] Updated Test and Simulation Results in Support o SAS-2 [Witt] SAS-2 6Gbps Test Results [Witt] SAS-2 Electrical Speciication Proposal [Witt]

2 Transmitter: Editor notes: Rob doesn t like transmitter device and receiver device because device has so many meanings. I have let them in place until a viable alternative is proposed. No maximum transition time is included since this is limited by the pk-pk voltage requirement. The minimum rise time may also be dropped as a result o the SCD22 plot. Transmitter equalization needs to be inormative rather than normative because o emphasis schemes and desire by large OEM s to have custom settings. A deault transmitter equalization value o 3 db is currently the recommended value. In some extraordinary cases, additional equalization is recommended. Common mode, return loss, and EMI concerns are speciied through s-parameter plots. Jitter: All indications are that the present measurement method using a type 1 ilter with a corner requency o baud/1667 will not allow measurement with SSC. Probably needs a type 2 ilter, but details need to be determined. General: Values need some amount o description or measurement methodology similar to what was done in SATA. Need pictorial representation. Transmitter device Min Nominal Max Units Bit Rate 6000 Mbps AC Coupling Cap (i attaches to SATA) 12 nf Dierential Voltage Swing (pk-pk) Vpk mv Transition Time (20%-80%) (0.25) ps (UI) Tx Equalization (inormative deault de-emphasis) db SDD22 Dierential Return Loss see Figure xxy db SCC22 Common Mode Return Loss see Figure xxy db Reerence Di Impedance 100 ohm Reerence Common Impedance 25 ohm SCD22 Dierential to Common Mode Conversion -12.7dB db (N value, see Figure xxz) Random Jitter 0.15? UI Deterministic Jitter 0.15? UI Total Jitter 0.3? UI

3 Equalization measurement The equalization measurement shall be based on two mode measurements using a TWO_DWORDS phy test pattern o D30.3 (see Table 215 in ). I the phy test unction is not supported, a vendor-speciic method may be used to produce this pattern. The voltage measurements shall be made with the transmitter device terminated through the interoperability point into a Zero Length Test Load. The ollowing ormula shall be used to calculate the equalization value: Vpk DE = db 20Log10 V The Vpk-Vpk and Vvma mode values shall be measured using the ollowing or an equivalent procedure: pk vma 1. An equivalent time sampling scope with a histogram unction shall be used. 2. The sampling scope shall be calibrated or measurement o a 3GHz signal. 3. The V pk -V pk mode value shall be determined as illustrated in Figure xxx. A sample size o 1000 minimum, 2000 maximum histogram hits shall be used to determine the values. (The histogram on the let o the test pattern signal displayed on the right.) 4. The V vma mode value shall be determined as done or V pk -V pk in step 3. V pk -V pk V vma Figure xxx Transmitter equalization measurement

4 or 50MHz < < 6 GHz SCC22 = max 6, * Log G SDD22 = max 10, * Log G Figure xxy Transmitter Dierential and Common Mode Return Loss or 100MHz < SCD11< max L,min H, N + S * Log10 3.0G r0 L = 26, H = 10, N = 12.7, S = 13.3 Proposal #2 TOLp 0.03 Cp: 0.94 pf TOLn 0 Cn: 0.7 pf Zo(kΩ): 0.05 skew: 5 ps -15 db < 6GHz L = 30, H = 6, N = 8, S = 26 SCD11 & SCD22 Limit 0 GHz S11 S22 SCD #NAME? 0.06 #NAME? ###### ###### ###### ###### ###### ###### ###### ### 0.10 #NAME? 0.63 #NAME? ###### ###### ###### ###### ###### ###### ###### ### 0.20 #NAME? 1.26 #NAME? ###### ###### ###### ###### ###### ###### ###### ### 0.50 #NAME? 3.14 #NAME? ###### ###### ###### ###### ###### ###### ###### ### #NAME? 6.28 #NAME? ###### ###### ###### ###### ###### ###### ###### ### 2.00 #NAME? #NAME? ###### ###### ###### ###### ###### ###### ###### ### 5.00 #NAME? #NAME? ###### ###### ###### ###### ###### ###### ###### ### #NAME? #NAME? ###### ###### ###### ###### ###### ###### ###### ### SATA TSATA RX GHz Figure xxz SCD22 Dierential to Common Mode Conversion

5 Receiver: Editor s note: There are some actors at the ar end that will complicate the receiver jitter tolerance speciication. Since the receiver is expected to have an equalization unction, a mathematical equalization equation will probably be needed to process the received signal at the compliance point to determine the resulting jitter is proper or testing the receiver device. Adrian to provide: Inormative physical test with an 800mV launch rom a compliant transmitter into a 10-meter ipass cable with some amount o jitter applied at the transmitter end, with SSC enabled, NEXT actively applied. Receiver to perorm data recovery at 10e-12 with 95% conidence level. Receiver device Min Nominal Max Units SDD11 Dierential Return Loss See Figure xyx db SCC11 Common Mode Return Loss See Figure xyx db Reerence Di Impedance 100 ohm Reerence Common Mode Impedance 25 ohm Common Mode Tolerance (2-200MHz) 150 mv Max Operational Dierential Input 6,0 Gbps 1200 mv Max Operational Dierential Input 1,5 and 3,0 Gbps 1600 mv Max Non-Operational Input Voltage 2000 mv Skew? Included in jitter? Receiver amplitude: Reerence receiver methodology could include

6 or 50MHz < < 6.0 GHz SCC22 = SDD22 = max 10, * Log 10 G 3.0 Figure xyx Receiver Dierential and Common Mode Return Loss