Patent ID: 8154332

Claim:
A current-controlled resistor comprising: a first input terminal configured to receive an input signal; a second input terminal configured to receive a current control signal; a first stage configured to receive at least part of the current control signal, the first stage including first and second PN diodes having respective first terminals of a first type and respective second terminals of a second type, wherein the first terminals of the first and second PN diodes are coupled to each other and wherein the second terminal of the first PN diode is coupled to the first input terminal; a second stage configured to receive at least part of the current control signal, the second stage including a third PN diode having first and second terminals of the first and second types, respectively, the second terminal of the third PN diode being coupled to the second terminal of the second PN diode of the first stage; and a first current mirror interposed between the second input terminal and the first terminals of the first, second, and third PN diodes, the first current mirror being configured to transmit part of the current control signal to the first stage and part to the second stage.