Method and apparatus for driving electrochromic display device

A method and apparatus for driving an electrochromic display device in which an electric current is applied only to one of display elements for which non-coincidence exists between an initially applied display information signal and a subsequently applied display information signal. In one preferred embodiment, a driver circuit comprises a latch circuit for storing a display information signal, a non-coincidence detection circuit for detecting non-coincidence between a subsequently applied display information signal and an initially applied display information signal stored in the latch circuit, and a signal generating circuit responsive to a non-coincidence signal from the detection circuit for generating an output signal for a display element for which non-coincidence is detected. In another preferred embodiment, a driver circuit comprises a latch circuit for generating an output at the instant delayed from a display information signal, and gate means for generating an output signal in response to the display information signal and the output from the latch circuit.