The DPI military/industrial-grade Unmanned Multirotor Aerial Relay (UMAR) tethered drone can provide 400+ hours of non-stop uptime and operations – at altitudes up to 500 feet – because of the continuous power flow through the tether. To achieve this, power needs to be delivered from the host vessel to the drone at extremely high voltage (500 – 800V) and low current to enable the use of the thinnest, lightest tether, which in turn enables greater drone mobility and larger airborne payloads. Also, high-voltage conversion must be achieved in the smallest possible footprint and lightweight profile. UMAR’s eight independent rotors require sophisticated, interconnected PCB circuitry, so any space savings enabled at the power-component layer can be repurposed for other value-add components.