Low power voltage reference circuit

摘要

A bandgap voltage reference circuit according to the present invention generates a constant reference voltage and is not affected by variations in a power supply voltage and in a manufacturing process. In the bandgap voltage reference circuit, a constant voltage supply unit supplies a constant voltage, a first current mirror mirrors a first current flowing through the constant voltage supply unit to generate a second current, and a second current mirror controlled by the constant voltage from the constant voltage supply unit mirrors the second current to generate a third current and outputs the third current to an output node. A voltage reference unit is connected to the output node to provide a reference voltage to the output node. The voltage reference unit includes at least one PMOS transistor and at least one NMOS transistor which are connected to each other in series or in parallel. Ion implantation processes for determining threshold voltages of the PMOS transistor and the NMOS transistor are simultaneously performed.