Current drive circuit for supplying driving current to display panel
View Patent ↗A current driver circuit includes a DA conversion part for generating a display current whose magnitude corresponds to a value of a displayed data, a timing control part for generating a write controlling signal, and a plurality of electric current latching parts, each of which generates a driving current. Each of the electric current latching parts having a capacitor generates a display current whose magnitude corresponds to a magnitude of a voltage to which the capacitor is charged. Each of the elective current latching parts performs a reset operation that once discharges the capacitor in response to a reset signal generated by the timing control part. The current driver circuit can generate the driving current with high accuracy and improve the speed of response to the display device.
1. A driving circuit for retaining a display current in response to a write controlling signal and outputting said display current as a driving current, said display current whose magnitude corresponds to a value of an input date being supplied by display current generation means in sequence, comprising:
a first switch for connecting and disconnecting a first node to and from a second node in response to a first write controlling signal, said display current being supplied to said first node;
a first transistor whose gate and drain terminals are connected to said second terminal and whose source terminal is connected to a common terminal;
a second switch for connecting and disconnecting said second node to and from a third node in response to a second write controlling signal;
a capacitor connected across said third node and said common node, for retaining an electric potential at said third node;
a second transistor connected across said third node and said common node, which is turned on in response to a reset signal supplied prior to said first and second write controlling signals; and
a third transistor whose gate and source terminals are connected to said third node and said common node, respectively, for outputting said display current from a drain terminal thereof.
2. A driving circuit for retaining a display current in response to a write controlling signal and outputting said display current as a driving current, said display current whose magnitude corresponds to a value of an input date being in sequence supplied by display current generation means, comprising:
a first switch for connecting and disconnecting a first node to and from a second node in response to a first write controlling signal, said display current being supplied to said first node;
a first transistor whose gate and drain terminals are connected to said second terminal and whose source terminal is connected to a common terminal;
a second switch for connecting and disconnecting said second node to and from a third node in response to a second write controlling signal;
a capacitor connected across said third node and said common node, for retaining an electric potential at said third node;
a second transistor connected across said third node and a bias electric potential, which is turned on in response to a reset signal supplied prior to said first and second write controlling signals, said bias electric potential whose magnitude corresponds to a value of said input data being generated; and
a third transistor whose gate and source terminals are connected to said third node and said common node, respectively, for outputting said display current from a drain terminal thereof.