| 摘要 |
<p>Conventionally, the luminances are different with the blocks of semiconductor circuits of current output type because of the variations of the semiconductor circuits when displaying is conducted on a single display panel by using the semiconductor circuits. In current output stages (14a, 14b), current-mirror circuits are provided at both ends of each chip to supply reference currents serving as references of gradation display from the ends. By increasing the resistances of the gate wires of the current-mirror circuits for distributing the currents to the outputs, the variations of the thresholds of the transistors in the chip are compensated so as to cause the output currents at the left and right ends to agree with each other. The reference currents are made equal to each other by interconnecting reference current generating resistors (11c to 11f) at least between the semiconductor circuits connected adjacently. Thus, the differences between the currents at both ends of all the semiconductor circuits are reduced to 1% or less, and the variation caused at the boundary of chips can be decreased.</p> |
