Designing a Boost-Switching Regulator with the MCP1650
Today's electronic circuits require a number of different voltage potentials. Powering silicon devices like microcontrollers or digital logic require a different voltage than bias supplies or powering strings of LEDs. A system can very easily contain a combination of circuits that require different voltages. With only a single input voltage delivered to the system, a power regulator is needed to produce the necessary voltages.
The power regulator can be an inductor-based, switchmode power converter, a switched capacitor charge pump or a linear regulator. Each regulator has it's own advantages and disadvantages, but it is the particular application requirements that determine which type of power regulator is best suited.
This application note focuses on inductor-based, switchmode power converters, more specifically ? the boost regulator topology. The boost is one of the fundamental switchmode power topologies. The other being the buck regulator. From these two topologies, all other switchmode power supply topologies are derived. The buck topology is used to provide a regulated voltage that is lower than the unregulated input voltage source. The boost topology produces a regulated output voltage that is higher than the unregulated input voltage source. An example of a boost regulator design will be explored using Microchip's MCP1650 boost controller.