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

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<math>I = (V_{2}-V_{1})(\frac{1}{200k}+\frac{I_{c}}{47.3})</math>
<math>I = (V_{2}-V_{1})(\frac{1}{200k}+\frac{I_{c}}{47.3})</math>


Thus, as the current <math>I_{c}</math> is increased, the effective resistance goes down, starting from a value of 200k (or whatever attenuator is used). For a completely linear system, the circuit of Fig. 5 can be used to get rid of the l/200k term.
Thus, as the current <math>I_{c}</math> is increased, the effective resistance goes down, starting from a value of 200k (or whatever attenuator is used). For a completely linear system, the circuit of Fig. 5 can be used to get rid of the <math>\frac{1}{200k}</math> term.


== References ==
== References ==