Amplifier

Patent metadata

Field	Value
Publication number	US-11290064-B2
Application number	US-202016861132-A
Country	US
Kind code	B2
Filing date	Apr 28, 2020
Priority date	May 2, 2016
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

An amplifier for a receiver circuit is disclosed. The amplifier has an input node (V in ) and an output node (V out ). It comprises a tunable tank circuit connected to the output node (V out ), a feedback circuit path connected between the output node (V out ) and the input node (V in ), and a tunable capacitor connected between an internal node of the feedback circuit path and a reference-voltage node. A receiver circuit and a communication apparatus is disclosed as well.

First claim

The invention claimed is:

1. An amplifier for a receiver circuit, the amplifier having an input node (V in ) and an output node (V out ), comprising:
a tank circuit coupled to the output node (V out );
a circuit path comprising first and second nodes and a third node situated between the first and second nodes, wherein the circuit path is coupled between the output node (V out ) and the input node (V in ); and
a tunable capacitor coupled between the third node of the circuit path and a reference-voltage node,
wherein the coupled circuit path is a passive circuit.

2. The amplifier according to claim 1 , wherein the circuit path comprises a series connection of at least one resistor and at least one capacitor.

3. The amplifier according to claim 2 , wherein the at least one resistor is tunable.

4. The amplifier according to claim 2 , wherein said at least one capacitor comprises a first capacitor, said at least one resistor comprises a first resistor coupled between the output node (V out ) and the first capacitor and a second resistor coupled between the first capacitor and the input node (V in ).

5. The amplifier according to claim 4 , wherein the third node of the circuit path is between the first capacitor and the second resistor.

6. The amplifier according to claim 1 , comprising a first transistor in common-source configuration.

7. The amplifier according to claim 6 , comprising a second transistor coupled in a cascode configuration between the first transistor and the output node (V out ).

8. A differential amplifier for a receiver circuit, comprising a first and a second amplifier, each according to claim 1 .

9. A receiver circuit comprising an amplifier according to claim 1 .

10. A communication apparatus comprising the receiver circuit according to claim 9 .

11. The communication apparatus according to claim 10 , wherein the communication apparatus is a wireless communication device for a cellular communication network.

12. The communication apparatus according to claim 10 , wherein the communication apparatus is a radio base station for a cellular communication network.

13. A receiver circuit comprising the differential amplifier of claim 8 .

14. The amplifier according to claim 6 , comprising an inductor coupled to the source terminal of the first transistor.

15. The amplifier according to claim 1 , wherein the tank circuit has a tunable center frequency.

16. The amplifier according to claim 1 , wherein:
the input node is coupled to an output node of another circuit of the receiver circuit; and
the tunable capacitor is configured to be tuned to cause the amplifier to have an input impedance that matches an output impedance of said another circuit at each of a plurality of center frequencies of the receiver circuit.

17. The receiver circuit according to claim 9 , wherein:
the input node is coupled to an output node of another circuit of the receiver circuit; and
the tunable capacitor is configured to be tuned to cause the amplifier to have an input impedance that matches an output impedance of said another circuit at each of a plurality of center frequencies of the receiver circuit.

18. The receiver circuit according to claim 13 , wherein in one or both of the first and second amplifiers:
the input node is coupled to an output node of another circuit of the receiver circuit; and
the tunable capacitor is configured to be tuned to cause the amplifier to have an input impedance that matches an output impedance of said another circuit at each of a plurality of center frequencies of the receiver circuit.

Assignees

• Ericsson Telefon Ab L M

Inventors

• Mu Fenghao

Classifications

• H03F3/195

  in integrated circuits · CPC title

• H04B1/18

  Input circuits, e.g. for coupling to an antenna or a transmission line (coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H) · CPC title

• H04B1/0082

  with a common local oscillator for more than one band · CPC title

• H03F1/342 Primary

  in field-effect transistor amplifiers · CPC title

• H03F2200/144

  the feedback circuit of the amplifier stage comprising a passive resistor and passive capacitor · CPC title