A data interface

The invention relates to a data interface device that is constructed so as to minimize electromagnetic interference in a liquid crystal display. The data interface device comprises a data input arranged to receive data which are synchronized with a desired frequency of a data clock. A clock modulator modulates the data clock so as to provide a modulated clock signal having a certain frequency in a certain range of frequencies so as to minimize electromagnetic interference when data is transmitted using the data clock . A variable data transmission rate controller is responsive to the modulated data and the clock to clock such that the transmission rate of data varies and minimizes electromagnetic interference.