| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppress variation in printing density. SOLUTION: Reference P-type transistors 16, 17a-17f are divided in a size ratio the same as a driving P-type transistor 11 and compensating P-type transistors 12a-12f and are made to be in one-to-one correspondences. The reference P-type transistors 16, 17a-17f are independently provided on a semiconductor substrate as are the driving P-type transistor 11 and compensating P-type transistors 12a-12f. As a result, it is possible to obtain a precise relative size ratio and to prevent variation in printing compared to a conventional way wherein one reference P-type MOS transistor is shared thereby.</p> |
