Silicon & Transceiver Validation Engineer

Cspeed IO is a stealth start up backed by Sutter Hills Ventures and Atreides Capital - headquartered in Palo Alto, CA.  Our executive team has a demonstrated track record of building and scaling category-defining semiconductor and infrastructure businesses at companies like Broadcom, Lumentum, Tesla, Apple, Samsung, Intel, and VMware.

Cspeed IO is developing next-generation optical semiconductor solutions for the AI infrastructure market, focused on enabling true “scale-up” architectures.  Our mission is to replace traditional copper interconnects with advanced fiber-optic technologies that overcome the limitations of existing optics solutions and architectures.

Overview

We are seeking a Silicon & Transceiver Validation Engineer to drive validation of our high-speed optical transceivers—from silicon characterization through module-level testing to host-system interoperability. You will review transceiver designs and requirements, develop comprehensive validation plans, and execute them in the lab across all major subsystems: Ethernet SerDes, internal data pipeline, laser and modulator control, mux/demux, and the MCU controller with EEPROM and I2C interfaces.

Key Responsibilities

• Review transceiver architecture and specifications; develop validation plans covering silicon, module, and system-level testing with defined coverage matrices and pass/fail criteria
• Characterize Ethernet SerDes performance (jitter, eye diagrams, BER, equalization) and validate internal data pipeline throughput across operating conditions
• Perform chip-level characterization across voltage, temperature, and process corners; drive root cause analysis with the SoC team
• Validate laser/modulator performance (output power, extinction ratio, wavelength stability) and mux/demux characteristics (channel isolation, insertion loss)
• Test MCU controller firmware interactions, boot sequences, EEPROM data integrity, I2C protocol compliance, and CMIS register map implementation
• Execute system-level functional validation, host interoperability testing (switches, NICs), and compliance verification (IEEE 802.3, CMIS, OIF)
• Develop and run reliability/stress test sequences (HTOL, LTOL, power cycling, thermal cycling)
• Build test setups and automation scripts (Python); create data collection and analysis pipelines; document procedures and results

Required Qualifications

• 5+ years of experience in hardware validation, silicon characterization, or transceiver testing
• Hands-on high-speed serial link validation: eye diagrams, BER testing, jitter analysis, S-parameter measurements
• Proficiency with lab instrumentation: real-time oscilloscopes, BERT, optical power meters, OSA, VNA
• Experience developing and executing structured validation plans from design specifications
• Understanding of transceiver architectures and subsystems (SerDes, TIA, driver, laser, modulator)
• Familiarity with I2C, SPI, and serial communication protocols; Python scripting for test automation
• BS/MS in Electrical Engineering, Physics, or equivalent

Preferred Qualifications

• Experience with NRZ optical transceiver validation and silicon characterization across PVT corners
• Familiarity with CMIS or similar management interface specifications
• Experience with Ethernet standards and compliance testing; equalization techniques and SerDes tuning (FFE, DFE, CTLE)
• Optical component characterization experience (laser IV/LI curves, modulator transfer functions)
• Experience in a startup or fast-paced development environment