Organic EL panel drive circuit and organic EL display device using the same drive circuit
AssigneeRohm Co., Ltd.
InventorsJun Maede, Shinichi Abe, Akio Fujikawa, Masanori Fujisawa
Life of this patent
Estimating the term…
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.
Claims19
An organic EL panel drive circuit as an IC for current-driving an organic EL elements through terminal pins of an organic EL display panel, comprising:
- a plurality of pads provided correspondingly to said terminal pins;
- a plurality of D/A converter circuits having current-mirror circuits constructed with unit transistors and provided correspondingly to said pads, respectively, said D/A converter circuits adapted to generate analog currents corresponding to display data for luminous display of said organic EL elements;
- and
- a plurality of transistor blocks each having a rectangular area in which at least two columns of unit transistors are formed, a width of the rectangular area in a pad arranging direction substantially corresponding to n times a pad pitch, where n is a positive integer,
- wherein unit transistors constituting the D/A converter circuits are selected from the unit transistors of the transistor blocks and the D/A converter circuits constructed with the unit transistors of the outermost transistor blocks are dummy circuits, which are inoperable for driving the organic EL elements arranged in a matrix.
An organic EL panel drive circuit as an IC for current-driving an organic EL elements through terminal pins of an organic EL display panel, comprising:
- a plurality of pads provided correspondingly to said terminal pins;
- a plurality of D/A converter circuits having current-mirror circuits constructed with unit transistors and provided correspondingly to said pads, respectively, said D/A converter circuits adapted to generate analog currents corresponding to display data for luminous display of said organic EL elements;
- and
- a transistor arranging block including a plurality of transistor blocks each having a rectangular area and width in an arranging direction of said pads and arranged with pitch, which is substantially n times an arranging pitch of said pads, where n is a positive integer, each said transistor block including at least two columns of unit transistors including at least two unit transistors arranged in the width direction of said transistor arranging block and a plurality of unit transistors arranged in a direction perpendicular to said pad arranging direction, said unit transistors constituting said D/A converter circuits being selected from an inside area of said transistor arranging block, said D/A converter circuits constructed with unit transistors formed in outermost side areas of said transistor arranging block in said direction perpendicular to said pad arranging direction being dummy circuits, which are inoperable for driving the organic EL elements arranged in a matrix.
An organic EL display device including an organic EL drive circuit formed as an IC for current-driving organic EL elements through terminal pins of an organic EL display panel, said IC comprising:
- a plurality of pads provided correspondingly to said terminal pins;
- a plurality of D/A converter circuits having current-mirror circuits constructed with unit transistors and provided correspondingly to said pads, respectively, said D/A converter circuits adapted to generate analog currents corresponding to display data for luminous display of said organic EL elements;
- and
- a plurality of transistor blocks each having a rectangular area in which at least two columns of unit transistors are formed, a width of the rectangular area in a pad arranging direction substantially corresponding to n times a pad pitch, where n is a positive integer,
- wherein unit transistors constituting the D/A converter circuits are selected from the unit transistors of the transistor blocks and the D/A converter circuits constructed with the outermost transistor blocks are dummy circuits, which are inoperable for driving the organic EL elements arranged in a matrix.
An organic EL display device including an organic EL drive circuit formed as an IC for current-driving organic EL elements through terminal pins of an organic EL display panel, said IC comprising:
- a plurality of pads provided correspondingly to said terminal pins;
- a plurality of D/A converter circuits having current-mirror circuits constructed with unit transistors and provided correspondingly to said pads, respectively, said D/A converter circuits adapted to generate analog currents corresponding to display data for luminous display of said organic EL elements;
- and
- a transistor arranging block including a plurality of transistor blocks each having a rectangular area having width in an arranging direction of said pads and arranged with pitch, which is substantially n times the arranging pitch of said pads, where n is a positive integer, each said transistor block including at least two columns of unit transistors including at least two unit transistors arranged in the width direction of said transistor arranging block and a plurality of unit transistors arranged in a direction perpendicular to said pad arranging direction, said unit transistors constituting said D/A converter circuits being selected from an inside area of said transistor arranging block, said D/A converter circuits constructed with unit transistors formed in outermost side areas of said transistor arranging block in said direction perpendicular to said pad arranging direction being dummy circuits, which are inoperable for driving the organic EL elements arranged in a matrix.
Dependencies are inferred from the claim text.