Switching amplifiers are a category of electronic devices rather than a specific brand. They are widely used in industrial automation, audio systems, and telecommunications for efficient signal amplification. Companies like Siemens (Germany), ABB (Switzerland), and Rockwell Automation (USA) produce switching amplifiers, which are known for their high efficiency and compact design. These amplifiers serve industries such as manufacturing, energy, and broadcasting, offering products like Class-D audio amplifiers and PWM-based industrial amplifiers.