摘要 |
A variable impedance circuit is disclosed which comprises a pair of diodes having their cathodes connected together, a first current source coupled to the connection between the diodes, and a second and a third current source which are connected to the anodes of the diodes respectively. The second and third current sources are controlled by means of current mirror circuits so that equal forward currents are caused to flow therefrom to the paired diodes, thus making it possible to set up a desired impedance variation range.
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