Buck converters (integrated switch) are not a specific brand but a category of voltage regulators widely used in power electronics. Major manufacturers like Texas Instruments (USA), Infineon Technologies (Germany), and STMicroelectronics (Switzerland) produce these components. They serve industries such as automotive, industrial automation, and consumer electronics, providing efficient DC-DC voltage step-down conversion. Key products include synchronous buck regulators, non-synchronous buck ICs, and modules with integrated MOSFETs, featuring high efficiency and compact designs for space-constrained applications.