A reference voltage generator is provided. The reference voltage generator includes a bandgap reference circuit, a level shifter and a voltage divider. The bandgap reference circuit includes a current generator and a first BJT. The current generator outputs a reference current. The first BJT flows in the reference current from its emitter via a first resistor and has its collector and base grounded, such that a bandgap reference voltage and a first bias voltage can be output at the connection between the current generator and the first resistor and at the emitter of the first BJT. The level shifter is coupled to the bandgap reference circuit and outputs a second bias voltage higher than the first bias voltage and unequal to the bandgap reference voltage. The voltage divider is connected between the second bias voltage and the bandgap reference voltage and outputs a reference voltage therebetween.