1. A pixel circuit comprising:
an organic EL element which emits light according to a drive current;
a storage capacitor which is charged with a data voltage;
a first driving transistor responsive to a charged voltage of the storage capacitor to supply a drive current to the organic EL element; and
a second driving transistor connected the storage capacitor and a predetermined power supply responsive to a potential corresponding to a voltage drop in the organic EL element, and supplies a charge current to the storage capacitor, wherein
means for causing the second driving transistor to supply charge current to the storage capacitor from a time when the storage capacitor is charged with the data voltage and the drive current from the first driving transistor flows through the organic EL element, and, when the drive current from the first driving transistor is stopped by a change in the charged voltage of the storage capacitor, the drive current is supplied to the organic EL element for a period corresponding to the data voltage and corresponding to a voltage drop of the organic EL element.
2. A pixel circuit as defined in claim 1, wherein the first driving transistor and the second driving transistor are p-channel transistors, a source of the first driving transistor is connected to a first power supply, a source of the second driving transistor is connected to a second power supply, and the second power supply has a voltage higher than that of the first power supply.
3. A pixel circuit as defined in claim 1, wherein the first driving transistor and the second driving transistor are p-channel transistors, sources of the first driving transistor and the second driving transistor are connected to a first power supply, and the second driving transistor is of depletion type.
4. A pixel circuit as defined in claim 1, wherein the storage capacitor includes a part which utilizes an organic layer of the organic EL element as a dielectric layer.
5. A display panel wherein pixels are arranged in a shape of a matrix, each of the pixels comprising:
an organic EL element which emits light in accordance with a drive current;
a storage capacitor which is charged with a data voltage;
a first driving transistor which is supplied with a charged voltage of the storage capacitor at a gate and supplies a drive current to the organic EL element; and
a second driving transistor which connects the storage capacitor and a predetermined power supply, is supplied with a voltage externally set, and supplies a charge current to the storage capacitor;
means for causing the second driving transistor to supply charge current to the storage capacitor from a time when the storage capacitor is charged with the data voltage and the drive current from the first driving transistor flows through the organic EL element, and, when the drive current from the first driving transistor is stopped by a change in the charged voltage of the storage capacitor, the drive current is supplied to the organic EL element for a period corresponding to the data voltage and corresponding to the voltage set outside the pixel.
6. A display panel as defined in claim 5, wherein the voltage externally set is alterable.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A die holding mechanism comprising a die push-up means that pushes up a die which is on a wafer sheet, and a die holding means that holds a die pushed up by said die push-up means, wherein:
said die is provided with connecting wires on an upper surface thereof;
said die holding means is provided with a connecting wire receiving shaft which is installed so as to be movable upward and downward, a pair of die holding levers which have die holding sections for holding said die and are installed on both sides of said connecting wire receiving shaft so that said die holding levers can open and close, and a die holding lever opening-and-closing means which opens and closes said die holding levers; and wherein
said die is pushed upward by said die push-up means, and said connecting wire receiving shaft is pushed upward during an upward movement of said die; and when said connecting wire receiving shaft is raised by a predetermined amount, said die holding levers are closed so as to hold said die, and said push-up needle of said die push-up means is lowered, thus allowing said die to be held by said die holding levers.
2. The die holding mechanism according to claim 1, wherein said die holding sections of said die holding levers are positioned beneath an undersurface of said die so as to hold said die.
3. The die holding mechanism according to claim 1, wherein said die holding sections of said die holding levers hold said die at side surfaces of said die.
4. A die packing device comprising:
a die holding means disposed so as to be movable upward and downward and to above a tray in which a die having thereon connecting wires is packed, said die holding means being provided with a connecting wire receiving shaft which is installed so as to be movable upward and downward, a pair of die holding levers which have die holding sections for holding said die and are installed on both sides of said connecting wire receiving shaft so that said die holding levers can open and close, and a die holding lever opening-and-closing means which opens and closes said die holding levers, and
a collet installed above said tray, said collet being rotatable and holding said die by vacuum suction; wherein
said collet receives said die from said die holding means, inverts said die so that said connecting wires face downward, and causes said die to be accommodated in said tray.
5. The die packing device according to claim 4, wherein said die holding sections of said die holding levers are positioned beneath an undersurface of said die so as to hold said die.
6. The die packing device according to claim 4, wherein said die holding sections of said die holding levers hold said die at side surfaces of said die.
7. A die bonding apparatus comprising:
a die holding means disposed so as to be movable upward and downward and to above a substrate to which a die having thereon connecting wires are bonded, said die holding means being provided with a connecting wire receiving shaft which is installed so as to be movable upward and downward, a pair of die holding levers which have die holding sections for holding said die and are installed on both sides of said connecting wire receiving shaft so that said die holding levers can open and close, and a die holding lever opening-and-closing means which opens and closes said die holding levers, and
a collet installed above said substrate, said collet being rotatable and holding said die by vacuum suction; wherein
said collet receives said die from said die holding means, inverts said die so that said connecting wires face downward, and causes said die to be bonded to said substrate.
8. The die bonding apparatus according to claim 7, wherein said die holding sections of said die holding levers are positioned beneath an undersurface of said die so as to hold said die.
9. The die bonding apparatus according to claim 7, wherein said die holding sections of said die holding levers hold said die at side surfaces of said die.