Position: Senior Signal Integrity Engineer High-Speed Active Electrical CablesLocation: Nashua, NH Position SummaryWe are seeking an experienced Signal Integrity (SI) Engineer to join our High-Speed I/O R&D team. The successful candidate will be responsible for the electrical design, simulation, validation, and optimization of next-generation Active Electrical Cables (AEC), optical transceivers, Linear Pluggable Optics (LPO), and high-speed networking products supporting 800G, 1.6T and future generation applications.
This role requires deep expertise in high-speed serial channels, DSPs, retimers, SerDes architectures, PCB design, cable assemblies, optical modules, and signal integrity analysis from concept through production.
ResponsibilitiesSignal Integrity Design & Analysis
- Develop channel architectures for high-speed copper and optical interconnect products.
- Perform pre-layout and post-layout SI simulations for channels operating at 224G PAM4 and beyond.
- Analyze insertion loss, return loss, crosstalk, impedance discontinuities, and channel compliance.
- Optimize PCB stack-ups, via structures, connector interfaces, cable constructions, and package transitions.
- Develop channel budgets and link performance models.
AEC and Copper Interconnect Development- Design and evaluate Active Electrical Cable (AEC) architecture utilizing DSPs and retimers.
- Perform channel simulations for DAC, ACC, and AEC products.
- Collaborate with cable suppliers on manufacturing feasibility and performance optimization.
DSP & Retimer Integration- Evaluate and optimize high-speed channels utilizing DSPs and retimers from leading semiconductor vendors.
- Analyze equalization performance, FEC impacts, CTLE, DFE, and adaptive link behavior.
- Support device bring-up, characterization, and compliance testing.
Laboratory Validation- Develop correlation between simulation and measured performance.
- Perform channel characterization using VNAs, TDRs, oscilloscopes, and BERT systems.
- Analyze eye diagrams, COM, SNDR, BER, jitter, and equalization performance.
- Support compliance testing and customer qualification activities.
Cross-Functional Leadership- Work closely with PCB design, mechanical, thermal, process, firmware, manufacturing, and supplier teams.
- Drive technical decisions related to channel architecture, stack-up selection, and manufacturing tradeoffs.
- Support customer design reviews and technical engagements.
Required Qualifications- BS, MS, or PhD in Electrical Engineering or related field.
- 5+ years of experience in high-speed signal integrity engineering.
- Strong understanding of high-speed serial interfaces and networking systems.
- Experience with 56G, 112G, and preferably 224G PAM4 technologies.
- Experience developing products using DSPs and retimers.
- Experience with active copper cables AEC, DACs, ACCs.
- Strong understanding of PCB design, stack-ups, via optimization, and transmission line theory.
- Experience with S-parameter analysis and channel modeling.
Preferred Experience- Experience with QSFP-DD, OSFP, OSFP-XD I/O cable assembly products
- Familiarity with Broadcom, Credo, Marvell, Astera Labs, or similar DSP/retimer solutions.
- Familiarity with CMIS and MSA specifications.
- Experience supporting NPI, qualification, and volume manufacturing.
Ansys HFSS, COM and IEEE channel compliance methodologies.
