Using a Buck Converter in an Inverting Buck-Boost Topology

To power some applications, generating a negative voltage from a positive input voltage source may be required. In such instances it is possible to configure the buck converter into an inverting buck-boost topology, where the output voltage is negative with respect to ground. This paper explains basic buck topology and inverting buck-boost topology, and addresses design considerations that must be taken into account when a nonsynchronous buck converter is used in an inverting buck-boost configuration.