The WCH CH341A is a versatile USB interface chip from Nanjing Qinheng Microelectronics (WCH) that provides USB-to-serial, USB-to-SPI, and USB-to-I²C functionality. It is widely used as a USB programmer for EEPROM, BIOS, and flash memory chips, as well as for debugging and embedded development tasks. The CH341A supports Windows, Linux, and macOS through dedicated drivers and utilities. Known for its low cost, broad protocol support, and reliability, it is popular among technicians, hardware hackers, and repair professionals for firmware flashing, device recovery, and hardware diagnostics.