Electronotes/AN-23 - The CA3080 as a voltage-controlled resistor: Difference between revisions

which is the same thing we had above. But here the current is drawn from the input (<math>I_{in} = I_{out}</math>) so the VCR looks like a resistor to ground, as seen in Fig. 2b. We can thus use this sort of VCR to implement the [[high pass filter|high-pass filter]] structure shown in Fig. 2c. The implementation is shown in Fig. 2d, and the 3dB frequency is <math>\frac{l1}{2 \pi R_{eq}C}</math>.