Patent ID: 7369125
Filing Date: 2008-05-06
Classification: G09G

Abstract:
1. A current supply circuit providing an output current corresponding to digital data of n bits (wherein n is an integer not less than 2), comprising: a current driving device; a current output node electrically connected to a first power supply node via said current driving device while current is being supplied by said current supply circuit; a current control circuit connected between a second power supply node and said current output node, receiving digital data, corresponding to the digital data, for controlling the current flowing in a current path, that includes said current output node and extends between the first and second power supply nodes, while current is being supplied by said current supply circuit; and a voltage regulating circuit receiving the digital data for forcing, after the current supplying starts, a change in voltage on said current output node, based on the digital data, said voltage regulating circuit including a plurality of internal nodes corresponding to respective bits of the digital data, a plurality of voltage sources corresponding to respective internal nodes, each voltage source independently supplying a respective voltage, a plurality of first switch elements respectively connected between respective voltage sources and internal nodes, a plurality of capacitors connected to respective internal nodes, and a plurality of second switch elements connected between said current output node and respective internal nodes, wherein each of said second switch elements turns on or off depending upon a corresponding bit of the digital data while current is being supplied by said current supply circuit.