Patent ID: 7193619

Claim:
A signal line driving circuit comprising: a first and a second current source circuits corresponding to each of a plurality of signal lines; a shift register, wherein the first current source circuit is disposed in a first latch and the second current source circuit is disposed in a second latch, wherein the first current source circuit is connected to a current source for video signal, wherein the first current source circuit comprises a first capacitive element, wherein the second current source circuit comprises a second capacitive element; wherein the first current source circuit converts a current supplied from the current source for video signal into a first voltage according to a sampling pulse supplied from the shift register, holds the first voltage using the first capacitive element, and supplies a current corresponding to the first voltage to the second latch, and wherein the second current source circuit converts a current supplied from the first latch into a second voltage according to a latch pulse, holds the second voltage using the second capacitive element and supplies a current corresponding to the second voltage to each of the plurality of signal lines.