| 摘要 |
PURPOSE:To reduce the installing space, to decrease the cost and to improve the reliability by connecting same types of resistors either in parallel or series or changing a characteristic of a semiconductor forming a resistance so as to vary the resistance thereby eliminating the need for an externally installing resistor. CONSTITUTION:Semiconductor integrated circuits 1, 2 are input buffer circuits with pull-up resistor and pull-down resistor attached and provided with a power supply line 3 of the circuits, a ground line 4, an internal signal line 5 for an input signal of both the circuits 1, 2, a totempole buffer 6 and same kinds of pull-up resistors and pull-down resistors 11, 12 and 21, 22 for the input buffer. The pull-up resistor and pull-down resistor groups for the resistors 12, 22 of the same kind of the resistors 11, 21 are connected in parallel with the pull-up resistors and pull-down resistors 11, 21. As a result, the combined resistance is decreased as 1/2, 1/3,.... Thus, the resistance is varied by connecting the same kind of the resistors in parallel and series or by changing the characteristic of the semiconductor to reduce the installing area, the cost and number of components. |
