US 6,320,468 B2 · Method and system for suppressing oscillations in a multi-stage amplifier

Abstract

A multi-stage amplifier for amplifying radio frequency signals includes a first amplifier stage having a first transistor and a second amplifier stage having a second transistor. The first transistor includes a first drain connected to a reference voltage through a first connection circuit. The second transistor includes a second drain connected to a reference voltage through a second connection circuit. The amplifier also includes a first transmission line connecting a portion of the first connection circuit to a portion of the second connection circuit and a resistive element connected in parallel with the first transmission line between the portion of the first connection circuit and the portion of the second connection circuit. The resistive element suppresses oscillation conditions at either of the first and second bias terminals.

Claims26

Dependent claims

A multi-stage amplifier for amplifying radio frequency signals, the amplifier comprising:

a first amplifier stage having a first transistor, the first transistor having a first bias terminal connected to a reference voltage through a first connection circuit;
a second amplifier stage having a second transistor, the second transistor having a second bias terminal connected to a reference voltage through a second connection circuit;
a first transmission line connecting a portion of the first connection circuit to a portion of the second connection circuit;
and
a resistive element connected in parallel with the first transmission line between the portion of the first connection circuit and the portion of the second connection circuit for suppressing oscillation conditions at either of the first and second bias terminals;
wherein the first connection circuit includes a second transmission line connected serially to a first bypass capacitor at a first node;
wherein the second connection circuit includes a third transmission line connected serially to a second bypass capacitor at a second node;
wherein the first transmission line connects the first and second nodes;
and
wherein the resistive element is connected in parallel with the first transmission line between the first and second nodes.

7 more elements

Dependencies are inferred from the claim text.

Method and system for suppressing oscillations in a multi-stage amplifier

Life of this patent

Method and system for suppressing oscillations in a multi-stage amplifier

Life of this patent

Abstract

Claims26