A voltage generating circuit, comprising: a rectification circuit having an input terminal adapted to receive a radio frequency signal, wherein the rectification circuit is configured to generate at least one auxiliary voltage (VPEG, VNEG) related to the radio frequency signal; and a voltage adjustment circuit coupled to the rectification circuit to receive the at least one auxiliary voltage (VPEG) and having at least one output terminal adapted to provide at least one bias voltage (Vbias, VREG) related to the radio frequency signal, the voltage generating circuit being characterized in that the voltage adjustment circuit includes a first voltage dividing component and a second voltage dividing component, a first terminal of the first voltage dividing component is coupled to the rectification circuit to receive the at least one auxiliary voltage (VPEG), and a first terminal of the second voltage dividing component receives a system voltage, a second terminal of the first voltage dividing component and a second terminal of the second voltage dividing component are coupled to the at least one output terminal of the voltage adjustment circuit, and that the voltage adjustment circuit provides the at least one bias voltage (Vbias, VREG) based on a selected one from the at least one auxiliary voltage (VPEG) and the system voltage. a rectification circuit having an input terminal adapted to receive a radio frequency signal, wherein the rectification circuit is configured to generate at least one auxiliary voltage (VPEG, VNEG) related to the radio frequency signal; and a voltage adjustment circuit coupled to the rectification circuit to receive the at least one auxiliary voltage (VPEG) and having at least one output terminal adapted to provide at least one bias voltage (Vbias, VREG) related to the radio frequency signal, the voltage generating circuit being characterized in that the voltage adjustment circuit includes a first voltage dividing component and a second voltage dividing component, a first terminal of the first voltage dividing component is coupled to the rectification circuit to receive the at least one auxiliary voltage (VPEG), and a first terminal of the second voltage dividing component receives a system voltage, a second terminal of the first voltage dividing component and a second terminal of the second voltage dividing component are coupled to the at least one output terminal of the voltage adjustment circuit, and that the voltage adjustment circuit provides the at least one bias voltage (Vbias, VREG) based on a selected one from the at least one auxiliary voltage (VPEG) and the system voltage. the voltage adjustment circuit includes a first voltage dividing component and a second voltage dividing component, a first terminal of the first voltage dividing component is coupled to the rectification circuit to receive the at least one auxiliary voltage (VPEG), and a first terminal of the second voltage dividing component receives a system voltage, a second terminal of the first voltage dividing component and a second terminal of the second voltage dividing component are coupled to the at least one output terminal of the voltage adjustment circuit, and that the voltage adjustment circuit provides the at least one bias voltage (Vbias, VREG) based on a selected one from the at least one auxiliary voltage (VPEG) and the system voltage.