A voltage selecting circuit includes: a first transistor, having a first terminal coupled with a first input terminal and having a second terminal coupled with a voltage output terminal; a second transistor, having a first terminal coupled with a second input terminal and having a second terminal coupled with the voltage output terminal; a first resistor positioned between the first input terminal and a control terminal of the second transistor; a second resistor positioned between the second input terminal and a control terminal of the first transistor; a first current adjusting circuit coupled with the control terminal of the first transistor; a second current adjusting circuit coupled with the control terminal of the second transistor; a comparison circuit for comparing voltages at the first and second input terminals; and a control circuit configured to operably control the first current adjusting circuit and the second current adjusting circuit.