An IO circuit capable of high voltage signaling in a low voltage BiCMOS process. The IO circuit includes a voltage rail generator circuit that receives a reference voltage and generates a voltage rail supply. A BJT (bi-polar junction transistor) buffer circuit is coupled to the voltage rail generator circuit and a pad. The BJT buffer circuit includes a pull-up circuit and a pull-down circuit. The pull-up circuit receives the voltage rail supply. The pull-down circuit is coupled to the pull-up circuit. The pad is coupled to the pull-up circuit and the pull-down circuit.