| 摘要 |
<p>PURPOSE:To reduce the cost, which is achieved by decreasing the number of signal lines and obviating the need of a large scale buffer, and to prevent the occurrence of noise by permitting a common signal generating part to apply a select signal to each set of light emitting element integrated arrays via a low current output buffer. CONSTITUTION:An LED head 8 is provided with segment drivers 21-1 to 21-4, LED arrays D1 to D40, a common signal generating circuit 2, etc. The segment drivers 21-1 to 21-4 are composed of a shift register 25, a latch circuit 26, an AND gate 27, a constant current buffer 28 and a buffer 29. A control signal CTR is input to the constant current buffer 28 via a terminal I6, and the buffer 28 controls the current value thereof, and outputs input video data D to the corresponding LED arrays from outputs Y1 to Y64. Each of the LED arrays D1 to D40 is formed with 64 LEDL1 to L64. However, this controller does not require a large buffer which discentralizingly supplies common signals C1 to C10 lighting and driving the LEDL1 to L64.</p> |
