Patent ID: 6316997
Filing Date: 2001-11-13
Classification: H03G

Abstract:
A variable gain amplifier comprising:first and second transistors, each having first and second terminals and a control terminal, the voltage between the control terminal and the second terminal of each transistor controlling the current flow through the transistor from the first terminal to the second terminal;a controllable switch circuit;first, second and third resistors;a capacitance; and,first and second current sources;the first and second resistors being coupled between the first terminals of the first and second transistors, respectively, and a first power supply terminal;the second terminals of the first and second transistors being coupled to a second power supply terminal through the first and second current sources, respectively, and to each other through the third resistor;the capacitance being controllably coupleable between the second terminal of the first transistor and the second terminal of the second transistor by the controllable switch circuit.