Current drive circuit and display
View Patent ↗A current drive circuit is provided with a bias generator and a current output unit; wherein the bias generator is provided with: p-channel MOS transistor, p-channel MOS transistor, and reference current source; and the current output unit is provided with: p-channel MOS transistor, switch means, p-channel MOS transistor, and output terminal.
1. A display, comprising:
organic EL elements that are arranged in a matrix;
current drive circuits and scan circuits for causing drive currents to flow to said organic EL elements,
wherein the current drive circuit comprises:
a current mirror circuit;
a current source for applying reference current input to said current mirror circuit;
a switch means to which output current of said current mirror circuit is applied; and
a cascode circuit for supplying the output current of said switch means as a drive current.
2. A current drive circuit comprising:
a bias generator that includes:
a first transistor in which a gate terminal and a drain terminal are connected together;
a second transistor in which a source terminal is connected to said drain terminal of said first transistor and a gate terminal and a drain terminal are connected together; and
a current supply that causes a reference current to flow to said second transistor; and
a current output unit that includes:
a third transistor in which a gate terminal is connected to said gate terminal of said first transistor;
a fourth transistor in which a gate terminal is connected to said gate terminal of said second transistor; and
a switch means that is provided between a drain terminal of said third transistor and a source terminal of said fourth transistor.
3. A current drive circuit according to claim 2 , further comprising:
a plurality of said current output units; and
a plurality of terminals that are connected to each of drain terminals of said fourth transistors of said plurality of said current output units.
4. A current drive circuit according to claim 3 , wherein each of said plurality of said current output units supplies as output a current that has been weighted.
5. A current drive circuit comprising:
a plurality of current drive circuits according to claim 2 ; and
a terminal that is connected to drain terminals of each of said fourth transistors of said plurality of said current drive circuits.
6. A current drive circuit according to claim 5 , wherein each of said plurality of said current drive circuits supplies as output a current that has been weighted.
7. A current drive circuit according to claim 1 , wherein said switch means is turned ON and OFF by a control signal.
8. A current drive circuit according to claim 2 , wherein said switch means is turned ON and OFF by a control signal.
9. A current drive circuit according to claim 7 , wherein said control signal is a graduation data signal of a display.
10. A current drive circuit according to claim 8 , wherein said control signal is a graduation data signal of a display.
11. A current drive circuit according to claim 1 , wherein said switch means is a MOS transistor.
12. A current drive circuit according to claim 2 , wherein said switch means is a MOS transistor.
13. A current drive circuit according to claim 3 , wherein said switch means is a switch group that includes a plurality of switch means, and said switch group decodes graduation data signals of a display.
14. A current drive circuit according to claim 5 , wherein said switch means is a switch group that includes a plurality of switch means, and said switch group decodes graduation data signals of a display.
15. A current drive circuit according to claim 13 , comprising a switch means that is connected to a source terminal of said third transistor.
16. A current drive circuit according to claim 14 , comprising a switch means that is connected to a source terminal of said third transistor.
17. A current drive circuit according to claim 15 , comprising a switch means that is connected to a source terminal of said first transistor and that is always in an ON state.
18. A current drive circuit according to claim 16 , comprising a switch means that is connected to a source terminal of said first transistor and that is always in an ON state.
19. A display, comprising:
organic EL elements that are arranged in a matrix;
current drive circuits and scan circuits for causing drive currents to flow to said organic EL elements; and
signal processing circuits for receiving image data signals as input, supplying graduation data signals to said current drive circuits, and supplying scan control signals to said scan circuits; and
wherein said display is provided with a current drive circuit comprising:
a current mirror circuit;
a current source for applying reference current input to said current mirror circuit;
a switch means to which output current of said current mirror circuit is applied; and
a cascode circuit for supplying the output current of said switch means as a drive current.
20. A display, comprising:
organic EL elements that are arranged in a matrix;
current drive circuits and scan circuits for causing drive currents to flow to said organic EL elements; and
signal processing circuits for receiving image data signals as input, supplying graduation data signals to said current drive circuits, and supplying scan control signals to said scan circuits; and
wherein said display is provided with the current drive circuit of claim 2 as said current drive circuit.