Analog Mixed-Signal Design and Modelling Engineer

About IonQ:

IonQ, Inc . [NYSE: IONQ] is the world’s leading quantum platform and merchant supplier - delivering integrated quantum solutions across computing, networking, sensing, and security. IonQ’s newest generation of quantum computers, the IonQ Tempo, is the latest in a line of cutting-edge systems that have been helping customers and partners including Amazon Web Services, and AstraZeneca achieve 20x performance results and accelerate innovation in drug discovery, materials science, financial modeling, logistics, cybersecurity, and defense.

In 2025, the company achieved 99.99% two-qubit gate fidelity, setting a world record in quantum computing performance.

This role is based at our Oxford, England (UK) office, with the option to work a few days a week remotely.

Up to 5%

1765

We are looking for a Staff Analog Mixed-Signal Design and Verification Engineer to join our Cryo-CMOS IC team at IonQ Oxford. In this role, you will design analog and mixed-signal blocks from specification through circuit design, simulation, layout, tape-out and silicon validation. You will also own top-level chip integration and modelling as a first-class part of our Cryo-CMOS development flow. In this you will build and maintain the model of the chip that the whole team simulates against, a mixed-abstraction model combining transistor-level circuits with Verilog-A/Verilog-AMS and System Verilog real-number behavioural blocks.

You will decide which blocks are represented at which level of abstraction, keep the models faithful to the schematics and measured silicon. The full-chip model will then be used to verify the ASICs that control the quantum processor from room temperature down to a few kelvin.

In this position, you will build and maintain the model of the chip that the whole team simulates against, a mixed-abstraction model combining transistor-level circuits with Verilog-A/Verilog-AMS and System Verilog real-number behavioural blocks. These models will be derived form first-principles mathematics and correlated against schematic and measured silicon. You will decide which blocks are represented at which level of abstraction, keep the models faithful to the schematics and measured silicon.

The full-chip model will then be used to verify the ASICs that control the quantum processor from room temperature down to a few kelvin.

You’ll have the opportunity to set the design and modelling standards the programme signs off against, making trusted models to inform tape-out decisions, and raise the design and modelling capability of the engineers around you, contributing directly to the success of IonQ’s quantum computing roadmap.

• Own the full-chip modelling strategy: model architecture, abstraction levels, accuracy targets and sign-off criteria used across the IC development flow
• Owning analog and mixed-signal blocks (references, DACs, switches, regulators, clock distribution) from specification through schematic design
• Own top-level integration: define block interfaces and specifications, assemble the top level, and run the full-chip mixed-signal simulations that verify the ASIC Develop Verilog-A and Verilog-AMS models of analog blocks and assemble them into a simulatable full chip
• Build real-number models so the full chip runs in digital verification and regression at practical speed
• Derive models from mathematics: turn a transfer function, a Z-parameter network description or a MATLAB analysis into robust Verilog-A with well-behaved tolerances
• Define and run model-versus-schematic correlation, keeping models in sync with design releases, and feed measured silicon behaviour, back into the models and the block designs
• Stand up mixed-signal co-simulation and regression (Cadence AMS Designer, Xcelium with Spectre) Lead block-level design reviews and mentor engineers on circuit design and modelling craft

To be successful, you will need deep analog and mixed-signal design and modelling experience, typically 10+ years. You will have designed blocks proven in silicon and models and used in production tape-out flows. You will bring expert…