Low-power, low-noise amplifier with negative feedback loop

Patent metadata

Field	Value
Publication number	US-11038475-B2
Application number	US-201916684431-A
Country	US
Kind code	B2
Filing date	Nov 14, 2019
Priority date	Nov 14, 2019
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

A low-power, low-noise amplifier with a negative feedback loop is provided. A low noise amplifier (LNA) includes a common gate (CG) amplifier, a common source (CS) amplifier having a gate connected to a source of the CG amplifier, a differential current balancer (DCB) connected to an output end of the CG amplifier and an output end of the CS amplifier, a symmetric load connected to the DCB, and a current bleeding circuit with one end connected to the output end of the CS amplifier and another end connected to the symmetric load, the current bleeding circuit including an active element and a load corresponding to the symmetric load, and an output end of the active element is connected to a gate of the CG amplifier.

First claim

What is claimed is:

1. A low noise amplifier (LNA) comprising:
a common gate (CG) amplifier;
a common source (CS) amplifier having a gate connected to a source of the CG amplifier;
a differential current balancer (DCB) connected to an output end of the CG amplifier and an output end of the CS amplifier;
a symmetric load connected to the DCB; and
a current bleeding circuit with one end connected to the output end of the CS amplifier and another end connected to the symmetric load, the current bleeding circuit comprising an active element and a load corresponding to the symmetric load, wherein an output end of the active element is connected to a gate of the CG amplifier.

2. The LNA of claim 1 , wherein the DCB comprises:
a first transistor with one end connected to the output end of the CG amplifier and another end connected to the symmetric load; and
a second transistor with one end connected to the output end of the CS amplifier and another end connected to the symmetric load.

3. The LNA of claim 2 , wherein in the DCB, a source of the first transistor is connected to a gate of the second transistor, and a source of the second transistor is connected to a gate of the first transistor.

4. The LNA of claim 3 , wherein the DCB further comprises:
a capacitor connected between the source of the first transistor and the gate of the second transistor and between the source of the second transistor and the gate of the first transistor.

5. The LNA of claim 1 , wherein the load corresponding to the symmetric load is implemented as at least one of a resistor, an inductor and a capacitor.

6. The LNA of claim 1 , wherein the active element is implemented as a transistor, and is connected between the CS amplifier and the load corresponding to the symmetric load.

7. The LNA of claim 2 , wherein the symmetric load comprises:
a first load connected to the first transistor; and
a second load connected to the second transistor.

8. The LNA of claim 7 , wherein an impedance of the first load is equal to an impedance of the second load.

9. The LNA of claim 7 , wherein an impedance of the load corresponding to the symmetric load is 1/(N−1) times the impedance of the first load and the second load, wherein N is greater than one.

10. The LNA of claim 1 , wherein a size ratio between the CG amplifier and the CS amplifier is 1:N, wherein N is greater than one.

11. The LNA of claim 1 , further comprising:
a capacitor connected between the active element and the gate of the CG amplifier.

Assignees

• Knu Lndustry Cooperation Found
• Knu Industry Cooperation Found

Inventors

• Kwon Ku Duck

Classifications

• H03F3/19

  with semiconductor devices only · CPC title

• H03F2200/451

  the amplifier being a radio frequency amplifier · CPC title

• H03F3/45179 Primary

  using MOSFET transistors as the active amplifying circuit (H03F3/45278 takes precedence) · CPC title

• H03F3/04

  with semiconductor devices only · CPC title

• H03F1/223

  with MOSFET's · CPC title