A buffer circuit, a display module, and a display driving method are disclosed. The buffer circuit comprises a first polarity buffer, a negative polarity buffer. The first polarity buffer receives a first supply voltage and a second supply voltage to output a first reference voltage to a first resistance string. The second supply voltage is less than the first supply voltage. The negative polarity buffer receives the second supply voltage and a third supply voltage to output a negative reference voltage to a negative resistance string. The third supply voltage is less than the second supply voltage.