Port Characterization & Troubleshooting
Enhancing SI Visibility with TDR, BER and More
Outline
- Host Life Cycle
- ML4035 Overview
- Port Troubleshooting Flow
- TDR Overview
- Cabled HCB Introduction
- Roadmap
- Test Coverage Guide
- MultiLane Advantages
Host Life Cycle
From Benchtop to Data Hall
ML4035 Overview
400G BERT | 35GHz Scope | TDR
4-Lane 53 GBd PPG:
- PAM4: 22-29.6 & 48-56 GBd
- NRZ: 22-29 & 48-56 Gbps
- DFE Pre-Coding & Gray Coding
- Channel Emulation & Full FEC
400G Bit Error Ratio Tester:
- Total DFE/FFE/CTLE equalization up to 13 dB
- FEC measurements
- Clock-data recovery
- BER counters
4-Lane 35 GHz Sampling Scope:
- High fidelity signal capture
- Jitter decomposition & NRZ/PAM4 full Eye measurements
4-Lane True-Differential TDR | TDT:
- High resolution TDR/TDT measurements
- Impedance profile measurements
- S-Parameters:
– Crosstalk
– Accurate multiport S-parameters
Automation SW
High throughput & affordable
Port Troubleshooting Flow
Beyond the Bit Error Rate
- Loopback module is first inserted for BER test
- If port BER is high, troubleshooting required
- TX path is tested using ML4035 Scope with CDR via HCB
- Impedance measurements help identify source of issue
- The ML4035 enables TDR Testing for port debug
TDR Overview
Time Domain Reflectometry with the ML4035
- Isolate impedance mismatches and discontinuities
- Pass/Fail verdict for each lane
- Standard & custom masks
- Gated TDR → hone-in on fault area (for instance, a bad connector or broken pin)
- Fast parallel measurements
- Sub ohm accuracy
- ~1 mm resolution
Efficient Characterization & Troubleshooting
Cabled HCBs & Switches
Cabled HCB: Transceiver-like connector with 2.4mm multi-coax cables
(available in Q3)
- RF cables and host plug integrated into one package
- Plugs directly into switch
- All major form factors (SFP, QSFP, QSFP-DD, & OSFP)
Cabled HCB with integrated Switch (available in Q4)
- Eight integrated 4:1 SE switches -> Test 16 differential lanes with a 4-lane tester
- Unlocks full port coverage (TX+RX) with a single plug
Roadmap
Test Coverage Guide
MultiLane Advantage
Why choose MultiLane?
MultiLane
- High value solution that includes BERT, DSO, TDR, & TDT
- High throughput (4 Diff Ports & Switch)
- User friendly & automated
- Compact & integrated size
- Single plug
Alternatives
- Expensive ($200k+)
- Low throughput (2 4 SE Ports)
- Test requires certified engineer
- Bulky, heavy instrument (ex. VNA)
- Multiple cable reconnections
