| 摘要 |
PURPOSE:To enable to select the desired logic circuit by a method wherein two pairs of circuits, each consisting of a logic circuit different from each other, are formed on one integrated chip and when the polarity of one side of the two power sources is a positive one, the polarity of the other side is changed in such a manner as to be a reverse polarity to the positive one. CONSTITUTION:When a power pin 3 of one side is set in a positive polarity and a power pin 10 of the other side is set in an negative polarity, voltage is loaded on an OR circuit 1, a control circuit 2 is actuated and a first circuit 15 acts as an NOR circuit, in which pins 12 and 13 are used as its input pins and a pin 14 is used as its output pin. When the power pin 10 and the power pins 3 are respectively set in a positive polarity and an negative polarity, voltage is loaded on an AND circuit 6, a control circuit 7 is actuated and a second circuit 9 acts as an NAND circuit, in which the pins 12 and 14 are used as its input pins and the pin 13 is used as its output pin. Accordingly, if the power pins 3 and 10 and the input/output pins 12, 13 and 14 may be connected in a state that an integrated circuit capable of displaying the desired functions is obtained at the time of aseembling. As a result, two kinds of integrated circuits are separately produced, thereby enabling to reduce significantly the man-hours in the control of their inventory independently to each other. |
