Buck-Boost Converters

Buck-Boost ConvertersDy, Charlton PaulOrtega, Rommel JoshuaStep up/down power converterOutput voltage can be either higher or lower than the input voltageNon-isolated (input and output share common ground) inverting or non-inverting power stage topologyBuck-Boost Converter

Buck-Boost ConverterNon-inverting Topology

Operation as a Buck Converter

Operation as a Boost Converter

Continuous Conduction ModeDiscontinuous Conduction ModeModes of OperationCurrent through the inductor never falls to zero during a cycle

Continuous Conduction ModeContinuous Conduction ModeAs a Buck Converter

As a Boost ConverterContinuous Conduction Mode

Amount of energy required by the load is small enough to be transferred in a time shorter than the cycleCurrent at the inductor falls to zero for some time near the end of the cycleDiscontinuous Conduction ModeDiscontinuous Conduction ModeAs a Buck Converter

As a Boost Converter

Discontinuous Conduction Mode

Battery-powered systemsInput voltage may vary widelyDecreasing battery charge

Applicationshttp://www.learnabout-electronics.org/PSU/psu33.phphttp://www.ti.com/lit/an/slva059a/slva059a.pdfhttp://en.wikipedia.org/wiki/Buckboost_converter

Sources