Executive Summary
BAE Systems uses buck power supplies to power various equipment that is sensitive to precise voltages. Although the power supplies perform adequately, the company desires to replace the analog feeback loops which control the output voltage with a digital design. Digital feedback loops provide flexibility, allow simplified circuit design with fewer required components, and allow the power supply to be reconfigured without changing the hardware design.
Various components were compared for the digital loop implementation, including field programmable gate arrays (FPGAs), microcontrollers, and digital pulse width modulation controllers (PWM controllers). We chose a Freescale HC12 microcontroller because it offered the following advantages:
The HC12 microcontroller interfaced well with common power circuit designs, particularly the well-known DC Buck Converter topology. Use of the microcontroller satisfied all our design objectives of low cost, real-time reconfigurability, and user interface capabilities. We are confident that BAE Systems will be pleased with our solution and will enjoy the added benefits of the power supply design.
Last updated: April 27, 2007
