Patent ID: 6774877
Filing Date: 2004-08-10
Classification: G09G

Abstract:
A current driver circuit, comprising:a current mirror circuit having at least a first transistor and a second transistor, said first transistor generating gate potential that accords with a drain current thereof, and said second transistor having a drain connected to a current-driven element, wherein application of a potential that accords with the gate potential of said first transistor to a gate of said second transistor causes said second transistor to drive said current-driven element at a current that accords with the drain current of said first transistor; holding capacitor for holding gate potential of said second transistor; a first switch element for connecting the drain of said first transistor to a signal line that provides a signal current in accordance with a received control signal; a second switch element that enters either a conductive state or a cutoff state in accordance with a received control signal, and that causes said current mirror circuit to operate when in the conductive state and that both prevents operation of said current mirror circuit and cuts off a charge/discharge path from said holding capacitor when in the cutoff state; a line for providing a source current of said first transistor and a source current of said second transistor; a third transistor that is inserted between said line and a source of said first transistor and that operates in a non-saturation region; and a fourth transistor that is inserted between said line and a source of said second transistor and that operates in a non-saturation region.