You will own the power distribution network from voltage regulator output to die bump — impedance, IR drop, droop and decoupling across package and board. Senior IC role: you own the PDN numbers that power delivery, SI and the package team design against.

What you will work on:

• PDN design and closure for a multi-die AI accelerator package

• DC IR, AC impedance, transient droop and electro-thermal analysis across die, package and board

• Decoupling strategy and optimisation across on-die, package and board tiers

• Package–board anti-resonance identification and mitigation

• PDN noise to jitter translation, closed back into the SI budget

Responsibilities:

• Analysis & closure: Build and close DC IR, electro-thermal, AC impedance and transient PDN analysis from VR output through package to die bump. Set target impedance per rail and hold the design to it.

• Chip power models: Work with CPM and workload current profiles to size on-die, package and board decoupling, and to predict droop across all three droop timescales.

• Resonance & mitigation: Identify package–board anti-resonance and cavity behaviour, and drive the plane, via and decap changes that mitigate it.

• SI coupling: Translate PDN noise into jitter through PHY supply sensitivity, and feed the result back into the channel budget.

• Vendor & validation: Drive CPM and model requirements with IP, PHY and package vendors. Correlate against PDN impedance measurement and on-die droop telemetry, and support bring-up and power debug.

Requirements:

• 8+ years in power integrity for high-speed digital systems, including package-level PDN work

• Hands-on with PDN extraction and simulation tools — Ansys SIwave/HFSS, Cadence Sigrity/Clarity or equivalent

• Real experience with DC IR, target impedance, transient droop and decap optimisation on a high-current rail

• Working knowledge of chip power models and how to apply workload current profiles

• Comfortable reading a package substrate stackup and bump map, and reasoning about plane, via and cavity behaviour

• Python scripting for automation and post-processing

Nice to Have:

• 2.5D, interposer, chiplet or advanced substrate PDN co-design

• PDN impedance measurement and on-die margin or droop telemetry correlation

• Electro-thermal co-simulation with the thermal team

• Familiarity with OCP rack-scale platforms and high-current delivery architectures

• Automated or AI-assisted engineering flows — PyAEDT, scikit-rf or similar

Why Semidynamics?

• Work for one of Europe’s most promising deep-tech semiconductor scale-ups.

• Accelerated development path.

• 4 days per week in the Barcelona office (city center), 1 day WFH.

• 1 week of work from everywhere in the world.

• Competitive package.

• A collaborative, technical, and growth-oriented environment that values direct ownership and clear thinking.