Abstract: A data driving circuit proofed against excessive pixel brightness because of overvoltage on the data line comprises a shift register circuit, a first latch circuit, a second latch circuit, a level shift circuit, a DAC circuit, and an output circuit. The second latch circuit detects a change in the MSB of the data signal of a sampled signal, and outputs a signal for applying a pre-operation of the current data line. When the MSB of the sampled signal is changed, the second latch circuit outputs a pre-operation enabling signal, and whether the grayscale value of the current data line is within a specified region. If within the specified region, the second latch circuit outputs an invalid signal, and the pre-operation is disabled.