A bandgap reference circuit is disclosed operating under a predetermined low voltage source. The circuit has a first circuit with a first differential amplifier for generating a first current, a second circuit with a second differential amplifier for generating a second current, and a bandgap reference voltage output module for combining the first current and the second current to output a bandgap reference voltage, wherein the first circuit and the second circuit complement each other for offsetting variations of the bandgap reference voltage due to temperature changes.