Patent ID: 6218899
Filing Date: 2001-04-17
Classification: H03F,H03G,H04B

Abstract:
A method of adjusting a gain of a linear amplifier, wherein said amplifier includes at least a pair of transistors, said method comprising the steps of:varying a set of impedances of said amplifier in a controlled linear manner so as to adjust said gain while maintaining a Third-Order Intercept Point (IP3) constant, wherein said varying step includes the step of:sequentially adding into a circuit path of said transistor pair an impedance value including one or more resistors each said resistor having associated therewith a MOS device operable for changing the effective resistance of said associated resistor, wherein said sequentially adding step includes the step of varying the gate voltage of said MOS device to control the effective resistance of said device; andadjusting bias conditions through said transistor pair consistent with the varying of said impedances.