Jack Brunning

Technical Consultancy

Continuation after transfer and sale of Gallium Semiconductor GaN IP.

Design, modelling and evaluation for a portfolio suite of high power GaN-SiC RF power devices for macro-BST in sub 6GHz telecom bands. Device design for Doherty, dual path and single ended configurations with and without internal pre-match using discrete, GaAs IPD and ACP package technologies. Part of the Gallium Semiconductor core team tasked with creating a high performing GaN technology group. • Design lead for a 400W packaged RF power device portfolio for macro-BST portfolio using a 50V GaN-SiC process node and GaAs IPD in the following bands. • 1.8-2.2GHz • 2.3-2.7GHz • 3.3-3.8GHz • 3.7-4.2GHz • Developed and integrated a complete EDA transistor design flow in Cadence MWO. • Developed 3D FEM + bondwire and package modelling for ACC, ACP and DFN packages in Cadence MWO. • Developed low power (60W) macro driver devices and linear RFPA demo. • Mentored junior team members in RFPA fundamentals, design and modelling techniques. • Alignment with external subcontractors. • Significant contributor to the establishment and development of the Nijmegen GaN R&D team.

Design, modelling and evaluation of GaN devices. Developed prototype integrated load modulated PA architectures and built knowledge base in early phase development environment. • Design, modelling, development, and evaluation of <6GHz GaN based load modulated power amplifiers. • Development of EDA modelling. • Characterization of semiconductor technologies across various process nodes. • Identification of potential IP opportunities and where appropriate, extraction of. • Contribute to competitor analysis and development of technology roadmaps. • Co-assist in the initial establishment of a Leeds based GaN team.

Design and modelling of discrete RF power devices for mobile broadband applications in sub 6GHz bands and 400 - 600W power ranges. • Design of high-power Si-LDMOS transistors for macro base-station applications in sub-bands 1.8 to 2.7GHz. • RF transistor design specifically for Doherty architectures. • S-parameter and load pull bench characterization of RF power transistors. • RF transistor modelling and measurement fitting. • Detailed line-up analysis and dimensioning for transmitter chain. • Designed concept and prototype for high power in a compact ceramic package study in 1.8 / 1.9 / 2.2 / 2.7GHz bands. Output of project suitable for high volume production and currently [2022] being released.

Provided detailed design knowledge and techniques with respect to modelling, Doherty architectures and load modulation design concepts for Horizon 2020 in house Early-Stage Researcher (ESR). Contributed as co-author to academic publications. Duties undertaken in parallel with current employment.

Detailed design and development of solid-state RF / Microwave power amplifiers (SSPAs) for surveillance, broadcast, military and commercial applications. • Single ended, balanced and load modulated (Doherty) solid state power amplifier design and development. • Use of Si-LDMOS and GaN-SiC transistor technologies. • Validation of transistor compact models. • Detailed line-up analysis and dimensioning for transmitter chain. • Authorship and presentation of technical feasibility studies and technology reviews.

Design and development of waveguide components (experience up to 20GHz) for commercial, space, military and scientific applications from initial customer specification, hardware design \ EM modelling, lab development \ testing, through to product delivery. • Design of waveguide components; tees, bends, comparators, high power loads, couplers. • 3D electromagnetic modelling and simulation using CST and HFSS packages. • Test \ measurement of waveguide components and systems. • Off-site antenna testing and qualification. • Basic mechanical test fixture design including design of test adaptors. • Working within a multi-disciplinary team alongside Mechanical Engineers. • Authorship of progress \ technical reports and design reviews with customers at home and abroad.

Development of passive components for CATV applications. • Design and prototype of lumped element diplexers, high\low pass filters (up to 1GHz) from initial customer specification, synthesis, EM simulation and layout through to testing, qualification, data sheets and product release documentation. • Basic test fixture design for lab development and testing purposes. • Test, measurement, characterization, and qualification of filters. • Product release of designs into volume production (400K+).

Development of 2.5GHz WiMAX radio for 20W and 40W variants from initial build to pre-production low volume production runs. • Radio lab tests. • De-bug of prototypes including RF, DC and baseband stages • Characterisation of radio performance • Evaluation of transmitter and receiver chains • Generation of failure mode analysis spreadsheets for prototype rounds against module specification

Awarded PhD scholarship funding by University of Liverpool. Research based on THz solid state power amplifier and transistor design. Research interests include: • THz transistors • Design of efficient passive combining at THz frequencies • SSPA design at THz frequencies • Fabrication for THz technologies • Linear and non-linear measurement techniques in the THz region • Solid state physics • Microfluidic cooling