Special function amplifiers are not a specific brand but a category of amplifiers designed for specialized industrial, medical, and scientific applications. They are produced by various companies worldwide, including Texas Instruments (USA), Analog Devices (USA), and STMicroelectronics (Switzerland). These amplifiers serve industries such as automation, telecommunications, and instrumentation, offering products like precision amplifiers, isolation amplifiers, and instrumentation amplifiers. They are critical for signal conditioning, noise reduction, and high-accuracy measurements in demanding environments.