Abstract: A method for supporting communication between a torch and a wire feeder or power source. The method includes superimposing a carrier signal on a DC trigger line voltage that is modulated to communicate data between the torch and the wire feeder/power source. The circuitry also supports conventional trigger line functionality.

Abstract: A power supply to provide welding or cutting power. The power supply may include an input rectifier to receive an AC input voltage from an input mains and output a rectified DC signal; a PFC/boost block to receive the rectified DC signal and output a boost DC signal having a predetermined voltage independent of the AC input voltage; an inverter to receive the boost DC signal, and output AC power to an output transformer; a PFC controller to control operation of the PFC/boost block; a control block to control operation of the inverter; an internal power supply to receive the rectified DC signal and output a first DC power signal to power the PFC controller, and output a second DC power signal to power the control block.