| 摘要 |
PURPOSE:To make it possible to determine the polygonal point or inclination of a polygonal line function by a simple circuit constitution by providing this polygonal line function generating circuit with switches for switching the gain of an operational amplifier and logical elements for controlling the switches in accordance with input voltage. CONSTITUTION:Resistors Rf1 to Rf3 are connected to an operational amplifier 1A through switches SW11 to SW13, SW21 to SW23 and the ON/OFF of respective switches is controlled by an EOR gate 3 and a NOR gate 4 in accordance with an input voltage level. For instance when Vth is set up as the threshold voltage of an IC including the switch 2, the EOR gate 3 and the NOR gate 4 and input voltage Vi is <(R1+R2).Vth/R2, voltage levels of points A and B is 'L'. Thereby the output C of the EOR gate 3 is turned to 'L', the output D of the NOR gate 4 is turned to an 'H' level and only the contacts SW13, SW23 are turned on. Consequently the gain of the amplifier 1A is determined by the resistor Rf3 and the inclination of a polygon line is expressed by Rf3/Ri1. |
