VoltaCo Consulting LLC provides electronic power conversion consulting services. We specialize in the design, qualification and application of DC/DC converters, AC/DC Rectifiers and Uninterruptible Power Supplies in power ranges from Point-of-Load modules to large scale power architectures. We are power electronics reliability experts and can assist in solving the most illusive application and reliability issues through the use of component physics of failure.www.voltaco.net

Product Reliability and Failure Analysis supporting development in Texas and China, manufacturing in Mexico and China and customers globally. Interfaced with customers in reviewing applications where power products have failed and recommended cost effective field action to mitigate future failures.• Performed RCA on 35W AC/DC Power Supply and concluded that the combination PFC/LLC controller contained an intrinsic flaw which caused switching MOSFET failures in THB. Identified film input filter capacitor susceptibility to moisture and worked with manufacturer to design a moisture resistant capacitor. Made recommendations to improve product robustness to successfully complete customer qualification.• Worked with router customer to resolve a POL module application issue, which resulted in intermittent operation upon start-up. Provided consultation to enhance customer’s analog measurement techniques.• Mentored team reviewing GaN MOSFET applications in DC/DC brick modules.

Component and Product Reliability supporting Development in Texas, California, Switzerland and China and manufacturing in Mexico, China and Poland.• Resolved repeated failures of 66W BMP DC/DC Converter in customer router deployed in Japan. Identified customer application susceptibility to atmospheric phenomena and recommended grounding and protection improvement to mitigate future occurrence.• Resolved catastrophic failure of 1MW UPS caused by 1200V IGBT shorting due to cosmic radiation susceptibility. Recommended replacement of IGBTs with radiation hardened devices affecting over 50MW at various datacenters through the US. Worked with IGBT manufacturer to mitigate cost increase for new device.• Deployed Design for Reliability (DFR) process globally thereby standardizing across all divisions. This resulted in product teams identifying reliability risks earlier in the development cycle and developing action plans to ensure products meeting reliability goals first time out.• Collaborated with Sourcing to achieve an immediate $250K cost reduction for high current DC circuit breakers by negotiating with Canadian supplier and recommending cost reduction through standardization of contact hardware. To date, realized over $600K in cost savings.

Component Engineering, Reliability and Supplier Quality supporting product Development and Sourcing in Texas and China and manufacturing in Mexico and China. Led a group of Component Engineers responsible for commercial components in Plano, Tustin and Shanghai as well as a Reliability Engineer and Global Environmental Compliance Leader in Plano.• Integrated Lineage Power Sourcing Quality Management System and Technical Regulations Standards as well as Design for Reliability and NPI processes into GE Energy’s processes ensuring best-in-class processes. • Defined a FRACAS system to integrate multiple development, customer quality and Design Archive of Mistakes databases into a single tool driven from the PLM system.• Improved DFM process by incorporating strain gage analysis of critical MLCC placement on PCB’s.• Led subcommittee responsible for updating IPC-9592B Derating Guidance and presented at APEC-2012• Conducted a study and documented the DC Bias Aging phenomenon of MLCC’s which causes the capacitance of MLCC’s to reduce, over time, beyond the datasheet specifications. This resulted in resolving a customer issue during HASS testing and improving the reliability of BMP’s, which use exclusively ceramic capacitors in energy storage applications.

Component Engineering, Reliability and Supplier Quality supporting product Development and Sourcing in Texas, California, India, Mexico and China and manufacturing in Mexico and China.• Resolved an issue caused by electrolyte diffusion through the rubber seal of an aluminum electrolytic capacitor used in the output of a 2KW Rectifier affecting over $2M revenue. This comprised of performing device accelerated life testing and weight loss measurements of suspect capacitors and securing manufacturer’s concurrence of the electrolyte to rubber seal mismatch. • Integrated component libraries, component selection and qualification processes from two acquisitions (Cherokee International and Peco II) into Lineage Power systems and processes ensuring best-in-class processes. • Deployed a global environmental compliance database and management system used to collect and analyze component material declarations and prepare product level material declarations for REACH, RoHS, WEEE, Conflict Minerals and other global environmental compliance regulations• Collaborated with Sourcing to regionalize custom parts supply base, notably sheet metal suppliers thereby increasing quality of piece parts. Qualified plating, cleaning and packaging processes for sub-tier suppliers thereby mitigating preponderance of white corrosion and cosmetic defect due to handling.• Collaborated on IPC subcommittee to develop the Derating Guidelines outlined in IPC-9592 Requirements for Power Conversion Devices for the Computer and Telecommunications Industries.

Component Engineering Team Leader supporting product development and manufacturing in Texas, Mexico and China.• Developed and globally deployed the Electronic Component Counterfeit countermeasures, Independent Distributor Qualification process and Broker Do Not Use process ensuring component authenticity through all modes of sourcing. GE Energy later adopted this as best-in-class practices.• Developed Electronic Component Leadless Package 2nd Level Solder Joint Reliability Qualification process used to qualify all new leadless packages prior to adoption into new designs.• Developed Switching Power Supply Training Course and Electronic Component Technology Training Course for Sr. Technicians and Jr. Engineers. • Led “Tiger Team” responsible for determining the root cause of power semiconductor failures in AC/DC rectifiers. For example, MOSFET failures in a 2N redundant power system causing multiple power module failures. The investigation uncovered a negative Vgs pulse in the high side FET of the asymmetrical half bridge due to the leakage inductance in the PWB layout. Developed an intricate snubber and clamp circuit on a daughter card which when installed under the MOSFET heat sink mitigated the spike without a major PWB layout change. • Studied Single Event Burn-out of power MOSFETs operating from a high voltage bus and deployed Recommendations for Derating High Voltage MOSFET’s; authored Power Systems’ Component Derating Guidelines; Design for Reliability Notebook and Lessons Learned; Guidelines for Paralleling Power MOSFET’s.• Qualified first commercialization of SiC 600V Schottky Rectifier for use in 760W Telecom grade Rectifier.

Electrical design team leader responsible for "internal Lucent customers" Off Line Switcher (OLS) power products. Focus on cost reduction effort and redesign to meet customer specifications on EMI and European EC standards. * Involved in reengineering a 4000-watt power system for a Lucent PBX in order to achieve a 25% cost reduction and recapture lost revenue from a competing power manufacturer. The system consisted of five 850W rectifiers, used in N+1 redundant mode, a battery interface unit and ten 810W DC/DC converters. * Designed a 290W UL, CSA and VDE certified, 3 output, power factor corrected Off Line Switcher. This included using a boost converter front end (to meet the PFC requirement) a two transistor forward converter for the main dc/dc converter and two magnetic amplifiers to control the auxiliary outputs. * Designed 810W UL, CSA and CISPR certified, triple output 48V DC/DC converter using a push-pull converter for the 5V, 60A main output and a 36W single transistor forward converter for the -5.2V auxiliary output. * Designed a 470W, 48V input, triple output DC/DC converter for a 2N redundant power system used in a disk array system in central office applications. Received US patent for innovative energy transfer circuit used for holdover of minor post-regulated outputs.