SelectLevel ID: PFSB-2

Description Role Overview

Semidynamics is seeking a Senior LPDDR5X Controller/PHY First-Silicon Bring-Up Engineer to support reconstruction, implementation and physical qualification of the LPDDR5X Controller/PHY initialization and training flow, taking controlled verification collateral through to deterministic first-silicon execution and failure diagnosis.

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.

Requirements Required experience

Demonstrable DDR/LPDDR post-silicon bring-up experience; LPDDR5/LPDDR5X experience is strongly preferred.

Strong understanding of memory-controller and PHY initialization, DRAM mode registers, timing configuration and frequency operating points.

Hands-on experience with PHY initialization firmware, mailbox/status flows, calibration and training procedures.

Experience diagnosing training failures and separating controller, PHY, DRAM, clock, reset and board-level causes.

Low-level C/C++ firmware development and direct MMIO/register access.

Ability to translate ordered verification sequences into deterministic executable firmware with readback, polling and bounded timeout handling.





Understanding of memory read/write sanity testing and the transition from training PASS to a usable memory configuration.

Practical laboratory experience during physical first-silicon memory bring-up.

Strongly preferred

Direct experience with Cadence DDR/LPDDR Controller and PHY IP.

Experience with Cadence PHY firmware/training flows or comparable commercial DDR PHY solutions.

LPDDR5X frequency switching, training checkpoints and known-good configuration capture.

Experience with first CPU-visible bandwidth measurements and controlled memory-performance evidence.

Experience correlating verification traces, register databases and physical-silicon results.

Expected responsibilities

Review existing DDR verification collateral and identify the authoritative initialization/training sequence.

Help convert the sequence into maintainable low-level C/C++ code rather than a blind register replay.

Define register access widths, masks, polling conditions and hardware-derived timeouts from authoritative specifications.

Integrate PHY firmware loading and controlled training/status flows.

Support first-silicon initialization, training, basic read/write and failure isolation.

Capture a controlled known-good configuration and reproducible evidence.

Support the transition to the first controlled CPU-visible read/write/copy bandwidth measurement.

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📌 Senior LPX Controller/PHY First-Silicon Bring-Up Engineer (Madrid)
🏢 Semidynamics
📍 Madrid