INTEGRATED CIRCUIT POWER TRANSISTOR ARRAY

摘要

A power transistor array integrated circuit includes an array of transistors, each having an electrode connected in common to a conductive line forming a part of the integrated circuit. The electrodes of the transistors are spaced along the conductive line and have a decreasing length in a given direction along the conductive line and have a decreasing length in a given direction along the conductive line. The conductive line has a corresponding increasing width in the given direction. The decrease in length of the electrode and the increase in width of the conductive line are such that the electrodes and the conductive line form a generally rectangular shape. Differences in turn-on voltage for the transistors resulting from the differences in their electrode length tend to compensate for voltage drop in the conductive line, thus giving uniform outputs from the transistors in the array. A region forming a reverse biased P-N junction to isolate circuit elements in the integrated circuit from one another is used as part of a conductive path to circuit ground and has a surface contact region of like conductivity and more highly doped than the reverse biased P-N junction region. The integrated circuit of this invention is especially useful as a thermal printhead driver circuit.