PhD students in PMIC circuit design for real time control of multi-level and multi-stage power converters

Job Description

Tyndall National Institute is an international leader in semiconductors, photonics and deep-tech research and innovation. As a leading collaborative European research institute, Tyndall is a key actor and hosting partner in the delivery of the 'Chips for Europe Initiative' (EU Chips Act).

Tyndall is Ireland's leading research and innovation organisation and it is the national focal point for excellence in deep-tech research, development and graduate training at the convergence of nanotechnology, microelectronics, photonics, electronics and AI. Tyndall is recognised as an international research leader in semiconductor, chip and digital technologies, particularly as applied to the fields of Information & Communications, Health & Life Sciences, Agritech & Food Security, Energy and Climate Mitigation, emerging fields such as quantum, and novel computing paradigms.

The Institute's key objective is to see frontier research activities having a significant impact on economic development and societal challenges in Ireland, Europe and beyond. Central to Tyndall's mission is delivering economic impact through research excellence in partnership with industry and academia. With an annual turnover of more than ???50m, the Institute has a community of over 600 researchers, engineers, support staff, postgraduate students, interns and industry researchers-in-residence.

With significant committed Irish government support, Tyndall will grow to be 1,000 people by 2030, with approximately 750 researchers, including 250 PhD students. A new 17,000 m2 research building is under development adjacent to the Cork headquarters and there are developing plans to expand Tyndall's existing Dublin research labs and to establish other research sites within Ireland.

Tyndall's expansion is also supported by recent national and EU funding wins for significant (M???10's) additional research equipment across a range of areas such as semiconductor processing, microscopy, quantum technologies, heterogeneous integration, ultra-high speed optical communications and RF through THz characterisation.

About the Team

MCCI is Ireland's national Microelectronics Circuits Research Centre. Hosted by Tyndall Research Institute MCCI has a large team of researchers in silicon chip design, at various stages of their careers, from PhD researcher through to Principal Researcher and all are creating world leading, innovative and high impact technologies, which will shape our future lives. Specifically, MCCI's mission is to carry out industry-driven, excellent research in areas such as Analog Precision Circuits, RF and High-Speed Transceivers, Cryogenic CMOS and Integrated Power Systems research.

Analog Devices Inc. (ADI) is the world's largest Integrated Device Manufacturer (IDM) in the power management field. Analog Devices is sponsoring two prestigious PhD research scholarships in CMOS Power Control ICs, based at MCCI's office at Tyndall National Institute Cork Ireland. Power and energy control are now defining the fundamental performances achievable in every single electronic system, from the RF powered medical implant through to the AI accelerator in the data-centre server. These positions will position the researcher at technology curve edge and be valuable to a diverse range of career areas.

About the Role

Generally, the power systems in every electronics hardware system or device are undergoing a number of major technology paradigm shifts, which is making power control central to achieving the continued performance improvements, which we expect in this "more than Moore" era.

From the grid AC electricity connection to the end application, there are typically five stage of power conversion. Powering architectures, such as those being architected through the Open Compute Project are changing so that end-to-end efficiency can be pushed into the high eighties, per cent. AT no-load standby and lighter loads, the goal is to design control modes so that every stage maintains maximum efficiency and minimum quiescent control power. The key application SoC, ASIC, CPU, MCU, AI Accelerator or GPU in every application is moving to a very fine geometry CMOS node with high digital gate leakage. The last stage of power conversion - the VR voltage regulator - is becoming highly integrated and splitting into hundreds of highly dynamic rails, which power application CMOS circuit blocks on and off precisely as required to implement fine-grained power delivery.

Driving this trend for a huge number of last-stage highly dynamic rails, also, is the tendency for applications to go multi-core - presently eight cores for a mobile phone and hundreds of cores in a computer server. These highly integrated rails deliver up to 20 A/ns and having very little local input decoupling (reservoir) capacitance, they push are pushing the requirement for high dynamic performance up-stream to other stages in the powering architecture, such as the 48 V - 5/12 V DC-DC modules. These modules, in themselves have recently migrated from 12 V input to 48 V input, to reduce distribution current RI2 power loss in system PCB traces. To "break" this voltage or converter it through a large down conversion ratio, there are a variety of emerging new multi-stage topologies combining switched capacitor stages with traditional switch-mode inductor-based stages. These new power topologies are achieving very high efficiencies and with their cascade of smaller inductor and capacitor energy storage elements, have the as yet, unrealised potential to achieve very high dynamic performances. These complimentary PhD research themes are specifically about innovating in the power control and management ICs for DC-DC converters, specifically with the goals of bringing high dynamic performance to hybrid multi-stage, multi-level flying capacitor (FCML) or hybrid resonant switched capacitor (ReSC) DC-DC converter.

PhD #1 Suggested Research Area

• High dynamic performance controller for multi-level, multi-stage FCML or ReSC. It is anticipated that a monolithic multi-level converter with high performance mixed-signal controller will be created. The controller will incorporate the best elements of today's non-linear, linear time invariant (LTI) and discrete time (DTLTI) control techniques to achieve accurate, highly dynamic, competitive and highly efficient power control over all loads.

PhD #2 Suggested Research Area

• Traditionally, switch mode converter controllers have been voltage-mode or current mode and have been classical PID or PI, respectively to control state-space averaged linear time invariant (LTI) system representations. There have been analog and digital (discrete time) versions. These systems achieve closed-loop control over the load voltage, dynamic set-point tracking and maintain fixed switching frequency for output noise spectrum control, but at the expense of high bandwidth ADCs, amplifiers and modulators. The challenges of achieving fast transient responses, high efficiency overload, lower CMOS complexity and area implementations resulted in a variety of non-linear hysteretic controllers, with varieties of constant on-time (COT), fixed-off time (FOT), adaptive on-time AOT, according to achieve various goals such as good line rejection. These controllers achieve lower cost implementations but have the drawbacks of variable switching frequency and some unpredictable output voltage ripples. More recently linear controllers are emerging which show promise with implementing time domain controllers using time, instead of voltage as the processed signal, using voltage controlled oscillators (VCOs) and voltage controlled delay lines (VCDLs). These controllers have digital type signals with CMOS 0-1 voltage levels. The research goal is to combine the best attributes of functionality implementations from the variety of control schemes to realise high performance control with low area digital type CMOS implementations which are substantially auto synthesisable and transferrable across CMOS geometries and achieve high dynamic performance, maintain over-load efficiency and generate controlled noise spectra. In short, the objective is to create low cost, synthesisable controller schemes, which deliver the performances associated with last stage VR controllers.

Key Responsibilities

• Complete your PhD research degree in high dynamic performance, real-time CMOS power management (PMIC). Your research will significantly advance the state-of-the-art from both research and commercial perspectives.
• Complete mixed-signal PMIC integrated circuit prototypes ("test chips") from concept, circuit design through silicon layouts, tape-out and silicon test characterization in the Design evaluation laboratory. These test chips will implement a complete integrated switch-mode power system including power path, gate drives and control, to showcase the noteworthy advancements made by your research.
• Perform experimental test characterisation of your stand-alone prototype PMIC test chips to showcase your advances in mixed-signal, high dynamic performance, real time power control as applied to select power topologies.
• Author or co-author peer-reviewed publications of international standing
• Engage in the dissemination of the results of the research, in other fora, as directed by and in conjunction with senior MCCI research staff. There will be presentations for in-house and company internal conferences.
• Manage/participate in education and public outreach engagement activities, as required.
• Ensure all activities are compliant with MCCI Processes and the Tyndall Quality Management System
• Carry out any additional duties as may reasonably be required within the general scope and level of the post.

About You

• You will be ambitious to achieve a high-quality research PhD through publications in pre-eminent tier 1 conferences and journals from University College Cork
• You plan to dedicated to a strong technical career in the area of power management with advanced digital control

Essential Criteria

• The ideal applicant will have a 1st class honours degree in electronic engineering or related discipline.
• Evidence of a strong desire to innovate and pursue advanced research.
• Evidence of being highly analytical, with good interpersonal and organisational skills
• Strong fundamental knowledge in core disciplines such as engineering mathematics, analog circuits, control systems theory and power electronic systems
• Strong technical writing and communications skills

Desirable Criteria

• Master's Degree in a relevant research area in electronics
• Specialised modules at under-graduate level in CMOS IC design, power electronics, control system design or digital signal processing
• Good understanding of switch-mode converter design and magnetic component operation
• Good understanding of continuous and discrete time controller design methodologies
• Experience with mixed-signal IC design
• Experience with mathematical modelling tools, such as MATLAB or Python
• Experience with integrated circuit design tools, such as Cadence/ Mentor

What we offer

• You will have the opportunity to pursue your research to the highest level in a world-class CMOS technology design center that has a young, dynamic, vibrant and self-driven research environment. You will be part of a large, collegial and supportive team of researchers at all levels of experience and across a variety of relevant disciplines, such as thin-film magnetics, signal processing and data-converters.
• There will be a 6-month internship at Analog Devices Ireland Design Centre Office at the beginning of the PhD period.
• There is an excellent research environment, which is co-located with many world leading research groups, such as Tyndall's Integrated Magnetics group. Tyndall Research Institute and MCCI together host over 500 researchers, with approximately 150 pursuing PhD research.
• These PhD research themes are of strong strategic relevance to the sponsoring company and as such there will be access to company expertise, through means such as internal corporate technical conferences or internship at an ADI site.
• Great career development and advancement that is highly visible to the semiconductor industry through direct contact with the sponsoring company, other MCCI member companies' base and through IEEE publications and conferences.
• Opportunities to publish and present at the leading conferences such as IEEE Solid-State Circuits conferences will be very strongly supported and indeed will be your primary focus
• Attend training courses and workshops, use the latest industry CAD design tools
• A generous tax-free scholarship stipend payment including tuition fees covered
• 20 days per annum annual leave for full-time research students, in addition to public holidays.
• Full coverage of travel expenses to international conferences to present project outcomes.
• Training and development opportunities are also provided.
• Mardyke Sports Arena -Students - free when registered with UCC
• Free Park and Ride Service

Terms of Studentship

Contract : Full Time/ Fixed Term

The annual stipend is ???25,00.00 for 4 years. In addition, annual tuition fees will be paid by the Tyndall National Institute.

Informal enquiries can be made in confidence to Hugo Cruz and John Morrissey.