| 摘要 |
PURPOSE:To obtain a level adjuster which is high in universal applicability and accuracy, by respectively connecting an input resistance and a feedback resistance using, a switch capacitor equivalent resistance with operational amplifiers through switching means which can reversibly switch the connecting relations to the operational amplifiers. CONSTITUTION:The input resistance R1 and the feedback resistance R2 are constituted of a switch capacitor equivalent resistance, etc., and independently drived by clock signals supplied from the outside and, since the clock signals are variable in frequency, the resistance values of the input and feedback resistances R1 and R2 can optionally be changed. When such combination of the input and feedback resistances whose resistance values can optionally be changed by external clock signals are connected through switching means S1-S4 which can reversibly switch the connecting relations to operational amplifiers OP, the combination of the resistances can be enlarged further. Therefore, level adjustment is made possible over a wide range from attenuation of input signals to amplification.
|
