New Design
Custom transformer and magnetics design
Buildable specifications for transformers, inductors, chokes, and specialty magnetic components.
Advanced Magnetics Design
Custom transformer engineering and inductor design consulting for power electronics.
Advanced Magnetics Design helps engineers and manufacturers design, review, troubleshoot, and reverse-engineer custom transformers, inductors, chokes, high-voltage magnetics, and hard-to-source specialty magnetic components.
Primary specialty
High-frequency custom transformers and inductors for power-conversion equipment.
Also supported
Reverse engineering, second-source replacements, chokes, current-sense transformers, and specialty high-voltage or low-frequency work.
When custom magnetics are needed
Custom magnetics bridge the gap between the power source, circuit topology, and electrical output the equipment requires.
Services
Custom transformer, inductor, choke, and magnetics engineering support.
Start with a new requirement, an existing sample, a failed prototype, incomplete documentation, or a production issue. Advanced Magnetics Design develops the component details and documentation needed for review, quotation, prototype build, or manufacturing transfer.
From Sample
Transformer reverse engineering
Exact-copy teardown, missing winding data, obsolete parts, and second-source documentation.
Problem Review
Design review and troubleshooting
Overheating, saturation, failed hipot, leakage, regulation, noise, prototype issues, or build variation.
Replacement
Redesigns and second sources
Hard-to-source parts, incomplete drawings, production transfer, cost targets, and manufacturability cleanup.
Common Projects
Transformer, inductor, choke, and magnetics engineering support.
Common work includes new designs, design reviews, replacement documentation, reverse engineering, and troubleshooting for power-conversion and specialty magnetic components.
- Custom transformer design
- Flyback Transformer Design
- Audio and impedance transformer design
- LLC transformer design
- SMPS transformer design
- Custom inductor design
- Common-mode choke design
- Transformer reverse engineering
- Obsolete transformer replacement
- Transformer overheating and failure review
- High-voltage transformer design
Service
Typical inputs
Typical outputs
Custom magnetic-component design
Topology, voltage range, frequency, duty cycle, current targets, isolation needs, mechanical limits.
Core, winding, insulation, wire, termination, construction notes, and test requirements. See Flyback Transformer Design and Audio Transformer Design.
Redesigns and second sources
Existing drawing, sample, supplier issue, cost target, material constraint, required fit/form/function match.
Alternate construction, material substitutions, equivalent magnetic targets, updated build documentation.
Transformer reverse engineering
Physical sample, markings, operating information, available measurements, need for functional or exact replacement.
Electrical characterization, dimensions, pinout, winding details, material list, and drawing/specification package.
Magnetic design reviews
Customer drawing, sample data, prototype measurements, thermal data, known design concerns.
Review of winding structure, insulation system, saturation margin, heating risk, leakage concerns, and manufacturability.
Magnetic component failure review
Failed and known-good samples, waveforms, operating conditions, test data, production history.
Focused review of overheating, saturation, insulation failure, poor regulation, material issues, and build variation.
Capabilities
Switching-transformer experience, supported by broad custom-magnetics capability.
The main focus is custom transformer and inductor design for power electronics. Related magnetics work is supported when it fits the project need and available information.
Primary power-conversion work
- Flyback, forward-converter, push-pull, half-bridge, and full-bridge switching transformers
- Power inductors, PFC inductors, common-mode chokes, differential-mode chokes, air-core inductors, and gapped magnetic components
- Planar, foil, litz-wire, flat-wire, and conventionally wound magnetic components
- Core, winding, insulation, leakage, loss, thermal, and manufacturability tradeoffs for power electronics
Specialty and replacement work
- Encapsulated transformers, low-frequency laminated-steel power transformers, and tape-wound / ring-core toroidal transformers
- Audio transformers, impedance-matching transformers, current-sense transformers, autotransformers, and custom multiwinding transformers
- Second-source replacement, redesign, material substitution, and documentation recovery from drawings or samples
Engineering topics
- Core-material, core-geometry, and air-gap selection
- Turns, winding structure, wire, foil, litz-wire, and flat-wire design
- Flux-density, saturation, ripple-current, and energy-storage analysis
- Core loss, copper loss, skin-effect, and proximity-effect analysis
- Leakage inductance, interwinding capacitance, EMI, and regulation optimization
- Insulation system, creepage, clearance, thermal rise, and manufacturability review
Reverse-engineering deliverables
- Destructive reverse engineering for exact-replacement work, layer-by-layer documentation, and manufacturer quoting
- Non-destructive analysis for functional replacement designs when the original part must remain intact
- Electrical measurements, pinout, phasing, dimensions, core/bobbin details, and construction notes based on the selected analysis method
- Build documentation, material list, winding details, insulation notes, inspection points, and specification package
Design/Build Outputs
- Custom magnetic design or replacement component specifications based on customer requirements, samples, or available design information
- Core, bobbin, winding, insulation, wire, foil, litz-wire, tape, shield, and termination details
- Volt-second capability, turns, winding order, phasing, pinout, and construction documentation
- BOM, build notes, inspection points, test requirements, and specification package
Review and troubleshooting support
- Independent review of customer drawings, supplier data, prototypes, or incomplete magnetic-component documentation
- Focused investigation of overheating, saturation, poor regulation, leakage-inductance issues, insulation failures, and build variation
- Recommendations for prototype changes, second-source paths, documentation cleanup, and production handoff
Reverse Engineering
Reverse-engineer an existing magnetic component for exact-copy documentation, functional replacement, or second-source quoting.
Destructive teardown is available when the goal is detailed build documentation from a physical sample. Non-destructive characterization can also support a functional replacement when enough operating information is available.
View transformer reverse engineering
Destructive teardown
Best for exact-copy replacement, missing winding data, obsolete parts, and manufacturer quote packages.
Functional replacement
Best when the sample must survive and electrical operating information is available.
Build documentation
Output can include schematic, dimensions, electrical requirements, material list, winding data, test limits, and manufacturing notes.
Typical uses:
obsolete or unavailable parts, second-source replacement, failed or incomplete supplier documentation, production troubleshooting, manufacturing transfer, redesign support, cost reduction, and recovery when only a physical sample is available.
Sample handling:
do not ship samples until the project objective, required work, sample condition, and return-or-teardown expectations have been reviewed and agreed.
Reverse-engineering limits:
reverse engineering can document construction and measured behavior, but exact material grade, proprietary processing, and production variation may require engineering judgment or supplier confirmation.
Safety and approvals:
final safety certification, agency approvals, and production validation remain the responsibility of the product manufacturer unless separately contracted.
About
Transformer and magnetic-component design from a hands-on magnetics specialist.
I am Craig Lombard, founder and Principal Engineer at Advanced Magnetics Design. I have more than 30 years of electrical engineering experience, including over 12 years focused entirely on custom transformer, inductor, choke, and magnetic-component design.
My work focuses on practical magnetic components for switching power supplies, inverters, high-voltage equipment, isolation circuits, industrial electronics, and specialized electrical systems.
I have designed magnetic components ranging from one-off specialty parts to production components requiring voltage conversion, isolation, high-voltage output, current sensing, impedance matching, or custom magnetic performance.
I also served for more than a decade as electrical engineering manager for a custom magnetics design and manufacturing company, giving me direct experience with both the engineering work and the realities of building magnetic components.
Advanced Magnetics Design supports projects that begin with circuit requirements, customer samples, existing drawings, failed prototypes, or production issues. Work can include custom magnetic design, reverse engineering, redesigns, second-source replacements, design reviews, winding specifications, material lists, test requirements, and manufacturing documentation.
Start with the component, the requirement, or the problem.
Advanced Magnetics Design can begin with a new transformer requirement, an existing supplier drawing, a sample to reverse engineer, a failed prototype, production test data, or a thermal, regulation, isolation, saturation, or leakage-inductance issue that needs focused engineering review.
Project scope is reviewed before quotation so the work matches the required engineering depth, documentation, testing, and schedule.
Request engineering review / quote