| 摘要 |
<p>PURPOSE:To contrive a reduction in the area of an LED recording head, by providing a plurality of transfer gates tor setting a constant current, a plurality of polysilicon fuses and a plurality of pads at junction points, on a driver LSI chip. CONSTITUTION:The ON resistance of a transfer gate 23 is set to be 1.2 times that of a transfer gate 22, for example the ON resistance of a transfer gate 24 is set to be 1.2 times that of the transfer gate 23, and the ON resistance of a transfer gate 25 is set to be 1.2 times that of the transfer gate 24. Next, the ON resistance of the transfer gate 23 is selected through measurement of the quantity of light emitted from corresponding N LED elements in a driver LSI. In this case, a pulse of voltage is impressed between pads 14, 15 to cut off a polysilicon fuse 19, and the ON resistance of the transfer gate 23 is used as a resistance. The ON resistance of the transfer gate 25 is selected for lowering a driving current in an LSI. In this case, a pulse of voltage is impressed between pads 16, 17, and the ON resistance of the transfer gate 25 is used as its resistance.</p> |
