| 摘要 |
PURPOSE:To obtain a single unit composite device, in which the excellent points of the two mentioned below is utilized and the defective points of them are removed, by a method wherein the collectors and the drains of a bipolar transistor and an FET are connected commonly, a base and a source are directly connected, and an emitter and a source are connected through a resistance element within a semiconductor substrate. CONSTITUTION:A bipolar transistor 2, an FET3 and a P type semiconductor resistor 4 are provided on an N type Si substrate 1, and they are connected as prescribed. Bias V0 is given between the collector C and the emitter E of the element 2, the element 3 is brought into a conductive state by adding input V2 to the gate of the element 3, and a current I1 is applied to the resistor 4. When V1 is increased, the voltage drop of the resistor 4 is increased, and an operating voltage is added to the base B of the element 2, the element 2 is brought into a conductive state, and I2 beings to flow. At this time, the ON resistance of the entire device is mainly determined by the element 2, and it has minor ON resistance characteristics. Also, as the input resistance of the device is the input resistance of the element 3 itself, it is almost infinite. Through the above- mentioned procedures, the single unit device, whereon the excellent point of the elements 2 and 3 is utilized and their defective point is removed, can be mass produced at low cost. |
