Abstract: A drive circuit of an active matrix type organic EL display panel includes a drive current generator circuit for generating drive currents corresponding to the red, green and blue colors in a predetermined sequence in response to a RGB switching signal and a current switching circuit having a first, second and third output terminals corresponding to the respective red, green and blue colors, the current switching circuit adapted to select one of the first, second and third output terminals in the predetermined sequence in response to the RGB switching signal, generate currents for charging the capacitors of the pixel circuits for the red, green and blue colors in response to the drive currents and output the charging current to the output terminals.

Abstract: First analog currents are obtained through a plurality of switch circuits provided correspondingly to output pins of an organic EL drive circuit as drive currents or through output stage current sources. The first analog currents or the drive currents are compared by a comparator provided within the organic EL element drive circuit with a second analog current (reference current) or a current obtained by passing the second analog current through a current source corresponding to the output stage current source. A result of comparison is outputted externally of the organic EL element drive circuit. The drive currents are obtained sequentially at the output pins by turning the switch circuits ON one by one sequentially by a control circuit to sequentially obtain the result of comparison for the drive currents from the organic EL element drive circuit.

Abstract: A timing control signal for separating a display time period corresponding to one line horizontal scan period and a reset time period corresponding to a retrace period of horizontal scan is provided for each of R, G and B display colors. The display time periods for R, G and B display colors are determined by setting the reset time periods of the timing control signals according to externally set data, so that luminance for each display color is regulated.

Abstract: An organic EL element drive circuit includes a current mirror circuit, a first current output circuit for generating a current having a first value in response to an output current of one of output side transistors of the current mirror circuit and a current generator circuit. An input terminal of the organic EL element drive circuit is supplied with a current having a second value from a second current output circuit of another organic EL element drive circuit preceding to the organic EL element drive circuit, which has substantially the same construction as that of the first current output circuit, to generate a predetermined drive current and the input transistor of the current mirror circuit is driven by the predetermined drive current to generate the first current value corresponding to the second current value.

Abstract: An organic EL element drive circuit comprises a current mirror circuit including an input side transistor supplied with a predetermined current and a plurality of output side transistors provided correspondingly to terminal pins of an organic EL display panel, for obtaining drive currents to be supplied to the respective terminal pins, a switch circuit connected in parallel to or in series with the input side transistor of the current mirror circuit, a memory for storing display data indicative of luminous intensities of the organic EL elements driven through the terminal pins and a control circuit for ON/OFF controlling the switch circuit to cut predetermined current supplied to the input side transistor when the display data stored in the memory for one horizontal display line or for a part of the one horizontal display line indicates that the organic EL elements are not to be driven.

Abstract: Dummy circuits, which are not operated, are provided in transistor blocks, which are positioned in outermost side portions of a drive circuit forming area of an IC. Physical property-related stress of unit transistors constituting D/A converter circuits or the D/A converter circuits and output stage current sources, which are formed in the transistor block in an area between the outermost transistor blocks, are relatively even, so that current mirror circuits constituting the D/A converter circuits can be constructed with unit transistors having good pairing characteristics.

Abstract: In a D/A converter circuit including a current mirror circuit constructed with an input side transistor circuit and an output side transistor circuit, the input side transistor circuit comprises a series circuit of a first MOS transistor and a second MOS transistor and a first switch circuit connected in parallel to the first MOS transistor. Gates of the first and second MOS transistors are connected commonly and a source of either one of the first and second MOS transistors is connected to a drain of the other of the first and second MOS transistors and the second MOS transistor has a gate length shorter than a gate length of the first MOS transistor.

Abstract: Determination means determines for every column pin whether or not display data of a current horizontal scan period (display time period) is the same as that of a next horizontal scan line (display time period). When the display data for one horizontal line are identical, an anode of an OEL element is connected to this terminal pin and then the drive current of the OEL element having a cathode to be scanned next in the vertical direction becomes substantially the same. Then, when a next vertical line is scanned for the column pin having display data, which is determined as identical, the resetting of the OEL element is inhibited by the reset inhibit circuit and the generation of peak current in a next horizontal scan period (display time period D) is stopped.

Abstract: In the present invention, an input terminal of a flip-flop circuit in master slave form which is formed by connecting two inverters in a loop shape is connected to a first terminal via a first switch circuit, an output terminal of the flip-flop circuit is connected to a second terminal via a second switch circuit, a third switch circuit is provided between the path from the first switch circuit to the input terminal and the second terminal, a fourth switch circuit is provided between the path from the output terminal to the second switch circuit and the first terminal, and through turning ON the first and second switch circuits and turning OFF the third and fourth switch circuits the first terminal is rendered operable as an input terminal and the second terminal is rendered operable as an output terminal, and through turning OFF the first and second switch circuits and turning ON the third and fourth switch circuits the second terminal is rendered operable as an input terminal and the first terminal is rende

Abstract: In a D/A converter circuit including a current mirror circuit constructed with an input side transistor circuit and an output side transistor circuit, the input side transistor circuit comprises a series circuit of a first MOS transistor and a second MOS transistor and a first switch circuit connected in parallel to the first MOS transistor. Gates of the first and second MOS transistors are connected commonly and a source of either one of the first and second MOS transistors is connected to a drain of the other of the first and second MOS transistors and the second MOS transistor has a gate length shorter than a gate length of the first MOS transistor.

Abstract: An organic EL element drive circuit comprises a plurality of peak current generator circuits provided correspondingly to terminal pins of an organic EL display panel, for adding peak currents corresponding to pulse widths of predetermined pulse signals and a pulse generator circuit for generating the predetermined pulse signal including a first, second and third pulses having pulse widths thereof determined according to data, which are set externally of the pulse generator circuit. The pulse generator circuit sends the first pulse to the terminal pins of the peak current generator circuits provided for R display color as the predetermined pulse, the second pulse to the peak current generator circuits provided for G display color as the predetermined pulse and the third pulse to the peak current generator circuits provided for B display color as the predetermined pulse.

Abstract: A current mirror type D/A converter circuit is constructed with transistor cells each including a MOS transistor, a gate region of which MOS transistor has folded stripe configuration in a plan view thereof, or a current flowing direction in a channel of which is a folded stripe in plan view.

Abstract: A transistor for detecting current generated by an output side transistor of a current mirror circuit of an organic EL panel drive circuit and a control circuit including a current driven input stage and an output stage for driving the input side transistor of the current mirror circuit are provided. The input stage of the control circuit receives the detected current and a certain reference current and the output stage of the control circuit generates a drive current, which corresponds to a difference between the detected current and the certain reference current and drives the input side transistor of the current mirror circuit. The control circuit controls the detected current in such a manner that it becomes equal to the reference current and the current distributed to terminal pins of an organic EL panel becomes the reference current or a current corresponding thereto.

Abstract: First analog currents are obtained through a plurality of switch circuits provided correspondingly to output pins of an organic EL drive circuit as drive currents or through output stage current sources. The first analog currents or the drive currents are compared by a comparator provided within the organic EL element drive circuit with a second analog current (reference current) or a current obtained by passing the second analog current through a current source corresponding to the output stage current source. A result of comparison is outputted externally of the organic EL element drive circuit. The drive currents are obtained sequentially at the output pins by turning the switch circuits ON one by one sequentially by a control circuit to sequentially obtain the result of comparison for the drive currents from the organic EL element drive circuit.

Abstract: An organic EL element drive circuit comprises a current mirror circuit including an input side transistor supplied with a predetermined current and a plurality of output side transistors provided correspondingly to terminal pins of an organic EL display panel, for obtaining drive currents to be supplied to the respective terminal pins, a switch circuit connected in parallel to or in series with the input side transistor of the current mirror circuit, a memory for storing display data indicative of luminous intensities of the organic EL elements driven through the terminal pins and a control circuit for ON/OFF controlling the switch circuit to cut predetermined current supplied to the input side transistor when the display data stored in the memory for one horizontal display line or for a part of the one horizontal display line indicates that the organic EL elements are not to be driven.

Abstract: Dummy circuits, which are not operated, are provided in transistor blocks, which are positioned in outermost side portions of a drive circuit forming area of an IC. Physical property-related stress of unit transistors constituting D/A converter circuits or the D/A converter circuits and output stage current sources, which are formed in the transistor block in an area between the outermost transistor blocks, are relatively even, so that current mirror circuits constituting the D/A converter circuits can be constructed with unit transistors having good pairing characteristics.

Abstract: An organic EL drive circuit comprises a timing signal generator circuit for generating a plurality of second timing control signals sequentially delayed from a first timing control signal, a reset pulse generator circuit for selecting one of the plurality of the second timing control signals according to the predetermined data and generating a reset pulse having a front edge determined according to the selected second timing control signal and a rear edge determined by the first timing control signal and a switch circuit responsive to the reset pulse for connecting the terminal pins to a predetermined bias line to reset an organic EL element of an organic EL panel connected to the terminal pins. Luminance of the organic EL panel is regulated by regulating the display period according to the predetermined data.

Abstract: An organic EL element drive circuit includes a current mirror circuit, a first current output circuit for generating a current having a first value in response to an output current of one of output side transistors of the current mirror circuit and a current generator circuit. An input terminal of the organic EL element drive circuit is supplied with a current having a second value from a second current output circuit of another organic EL element drive circuit preceding to the organic EL element drive circuit, which has substantially the same construction as that of the first current output circuit, to generate a predetermined drive current and the input transistor of the current mirror circuit is driven by the predetermined drive current to generate the first current value corresponding to the second current value.

Abstract: A drive current having a peak current, for driving an organic EL display panel, is generated by generating the peak current in output side transistors of a current mirror circuit having a plurality of input side transistors by driving one of the input side transistors with a predetermined current and reducing an output current of the output side transistors from the peak current to a steady current by reducing the drive current per one input side transistor by branching the predetermined current to the other input side transistors connected in parallel to the one input side transistor.

Abstract: A timing control signal for separating a display time period corresponding to one line horizontal scan period and a reset time period corresponding to a retrace period of horizontal scan is provided for each of R, G and B display colors. The display time periods for R, G and B display colors are determined by setting the reset time periods of the timing control signals according to externally set data, so that luminance for each display color is regulated.