Hai H.

Experience

• Senior Electrical Engineer EchoNous Inc · Full-time Jul 2025 – Feb 2026 7 mos Redmond, WA, United States Responsible for designing and improving analog and digital circuits, firmware for tester in ultrasound devices. Ensured IEC60601 compliance. Worked with production to design products with low cost manufacturability and to specifications. Oversaw and guided PCB vendors to make sure fabrication done compliant to design requirements and standards.
  
  • Designed several adapters from scratch with rigid and flex portion to connect mainboard with ultrasound transducers. Use layers to shield signals from EMI and minimize crosstalk with routing techniques. Performed schematic capture, ces rules, layout, route, drc, dfx, dfm, fabrication files, assembly drawings, and mechanical checks.
  • Designed and implemented hardware with scripting to control the actuation of motor in testing USB cable.
• Senior Electrical Engineer React Health · Full-time Jan 2023 – Sep 2025 2 yrs 8 mos Redmond, WA, United States Developed the architecture and implemented the next generation of PCBs according to DO-160 guidance. Led the team to improve existing PCBA's reliability and minimize failures in production and field returns. Collaborated with crossfunctional team to define new process to improve outcome and productivity. Performed hardware validation, debugging, and failure analysis on PCB components and wire/hardness with great attention to detail.
  
  ● Redesigned using Altium the control board of an electrical systems including major functional blocks such as Power Management, RF circuits in modem, Buck, Boost, flow and pressure sensor, an FPGA, a Micro-controller, microprocessor, ADC, DAC, 3-phase Compressor Driver, Blower Driver and battery charger. Incorporated solutions found of existing issues in manufacturing and add new features. As a result, yield of the new boards increased by additional 16% in production.
  ● Ran simulation of a linear regulator to drive the DC motor to deliver oxygen with precision and minimal noise to eliminate disturbance onto customer equipment's oxygen line; thus, zero customer complaints after 1 year of service.
  ● Optimized surge detection circuit to better protect internal components from damage by high-current surge or shorts while accommodating the high power under worst-case load. Included fault tolerant system design and redundant operation for improving reliability and safety. Utilized statistical analysis to troubleshoot production equipment for repeatability and accuracy and to meet regulatory requirements and compliance.
  ● Minimized noise on the SPI and I2C bus between micro-controller and peripheral sensor boards, enabling reliable data reading from sensor and preventing ventilator from going into INOP.
  ● Assisted in manufacturing engineering, monitoring supplier performance to ensure quality, system integration, and compliance with requirements.
• Senior Electrical Engineer Aerojet Rocketdyne · Full-time Mar 2022 – Nov 2022 8 mos Redmond, WA, United States Researched, developed, designed, and tested the Modular Multilevel Converter (MMC) as a new High-voltage DC power conversion topology for military and space application to be deployed for Lunar Surface Project.
  
  ● Performed trade study between various DC-DC converter such as resonant converters, MMC, flyback, etc.
  ● Adapted and applied control theory; simulated the control system with compensation to achieve stability and optimal transient response for MMC under the variation of load. Implemented this system in PCB and verified same results were collected.
  ● Developed the prototype boards for RMS and peak current sensing with analog front-end chain including a sense resistor, RF Op-amps, 2nd-order SK filtering, peak detector, an A/D converter and an isolator. Researched and selected components based on performance, cost, and availability. Perform hardware functional testing on the prototypes to verify product reliability and performance. Therefore, isolated issues and saved debugging time for system integration and during bring-up.
  ● Evaluated half-bridge configuration using the GaN transistor class for its robustness against radiation, EMI severity, and MIL-STD requirements for space environment. Rating at 650V, 60A.
  ● As a team, successfully developed and demonstrated the functionality of MMC power conversion in a prototype achieving 95% efficiency, 1200V stepping down to 70V, 13.5A in a 1000W power system.
• Senior System Engineer Amazon Kuiper · Full-time Oct 2021 – Feb 2022 4 mos Redmond, WA, United States Responsible for designing RF circuits and verifying communication system for Hi-Rel and Space applications.
  ● Developed a fifth-ordered analog filter using Sallen-Key and multi-feedback amplifier to obtain the right DC gain, low noise, low power, and low EMI effects for optical satellite communication. Analog signals converted to digital via parallel ADCs and communicated with CPUs/MPUs via LVDS SPI bus. Supervised the layout of this PCB to comply with IPC-A610 class III for space applications. Tested and collected successful test data for this module.
  ● Modeled and analyzed mathematically and thru circuit simulation the noise figure of the aforementioned analog frontend when designed in various gain combination for each amplifier stage, then chose the best combination for noise performance. Result showed a reduction of noise by 75% from its first design, an improvement in SNR for ADC.