| 摘要 |
PURPOSE:To obtain the switched capacitor amplifier which suits to IC-implementation and obtains an optional amplification degree at a switching frequency by connecting switched capacitor equivalent resistances which are variable in frequency and operate mutually with opposite-phase clocks to the feedback side of an operational amplifier and also connecting a switched capacitor equivalent resistance which operates at a variable frequency to its input side. CONSTITUTION:When clocks phialpha and phialpha', and phibeta and phibeta' for switching are controlled, an output voltage V0 is pumped up every time the clock phibeta turns on. Therefore, the output voltage V0 is eventually as shown by an equation I. When switched capacitors are all equal, the equation I becomes an equation II. The figure shows that a final output 3sinomegat is sampled as an output Vs by a sample and hold circuit A with the sampling clock phialphas, but the final output is only sampled at a frequency falphas twice as high as the frequency falpha of the clock phialpha. |
