In a data driver 10A of a dot-inversion driving type, the outputs of voltage buffer amplifiers B1 to B12 are connected to respective data bus lines D1 to D12 of a LCD panel, short-circuiting switches S1, S3, S5, S7, S9 and S11 are connected between ones of every other adjacent data bus lines concerned with the same display color, and interconnecting lines on first and second rows are arranged in a staggered configuration. These short-circuiting switches are formed at one sides of every other data bus lines, and turned on by a control circuit 13 when the outputs of the voltage buffer amplifier are in a high impedance state.