The invention provides a serial link transmitter coupled to a serial link receiver through a pair of transmission lines and having a pair of transmitting terminals respectively coupled to one of the transmission lines. The serial link transmitter comprises a differential amplifier and a voltage clamping circuit. The differential amplifier generates a pair of differential output voltages on the transmitting terminals according to a pair of differential input voltages for transmitting data to the serial link receiver, and the differential output voltages are transmitted with a common mode voltage to the serial link receiver during data transmission. The voltage clamping circuit clamps the pair of differential output voltages of the transmitting terminals to the common mode voltage before the serial link transmitter transmits data to the serial link receiver.