Apparatus and methods for low noise amplifiers

• US 10,340,861 B2
• Filed: 10/12/2017
• Issued: 07/02/2019
• Est. Priority Date: 11/18/2016
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Ye, Peihua, Pehlivanoglu, Engin Ibrahim, Marsan, Eric J.
• Primary Examiner(s): Nguyen, Khanh V
• Assistant Examiner(s): Nguyen, Khiem D
• Application Number:
  US15/782,032
• Publication Number:
  US 20180145648A1
• Time in Patent Office: 628 Days
• Field of Search: 330 51, 330151, 330 86, 330110, 330302, 330305, 330306, 330282, 330311
• CPC Class Codes: H03F 1/0277 Selecting one or more amplifiers from a plurality of amplifiers
• CPC Class Codes: H03F 1/223 with MOSFET's
• CPC Class Codes: H03F 1/26 Modifications of amplifiers to reduce influence of noise generated by amplifying elements
• CPC Class Codes: H03F 2200/06 A balun, i.e. balanced to or from unbalanced converter, being present at the input of an amplifier
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2203/45611 the IC comprising only one input signal connection lead for one phase of the signal
• CPC Class Codes: H03F 2203/7236 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers by (a ) switch(es)
• CPC Class Codes: H03F 3/193 with field-effect devices H03F3/195 takes precedence
• CPC Class Codes: H03F 3/21 with semiconductor devices only H03F3/245 takes precedence
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/72 Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal

Abstract

Apparatus and methods for low noise amplifiers (LNAs) are provided herein. In certain configurations, an LNA includes a gain stage and a bypass stage electrically connected in parallel with one another between an input and an output. The bypass stage and the gain stage are selectively activated based on a mode of the LNA. For example, the gain stage provides inverting amplification to an input signal received at the input in a gain mode. Additionally, the bypass stage provides a low gain path from the input to the output in a bypass mode. Additionally, the bypass stage includes a balun that provides inversion to the bypass stage such that a phase delay through the bypass stage is similar to a phase delay of the gain stage.

Claims

1. A wireless communication device comprising:

a low noise amplifier including a mode control circuit configured to operate the low noise amplifier in a selected mode chosen from a plurality of modes including a first gain mode and a bypass mode, a first gain circuit electrically connected between an input terminal and an output terminal and operable to provide inverting amplification to a radio frequency input signal received at the input terminal in the first gain mode, and a bypass circuit electrically connected in parallel with the first gain circuit between the input terminal and the output terminal, the bypass circuit including a balun operable to provide an inversion to the radio frequency input signal in the bypass mode so as to compensate for a difference in phase delay between the bypass circuit and the first gain circuit; and

an antenna configured to provide the radio frequency input signal to the low noise amplifier.

2. The wireless communication device of claim 1 wherein the low noise amplifier further includes a phase compensation circuit electrically connected to the output terminal and configured to further compensate for the difference in phase delay.

3. The wireless communication device of claim 2 wherein the phase compensation circuit includes a plurality of capacitors that are digitally selectable.

4. The wireless communication device of claim 2 the low noise amplifier further includes a serial interface configured to receive data operable to control an amount of phase adjustment provided by the phase compensation circuit.

5. The wireless communication device of claim 2 wherein the balun is operable to provide a coarse phase adjustment and the phase compensation circuit is operable to provide a fine phase adjustment.

6. The wireless communication device of claim 1 the low noise amplifier further includes an input matching inductor electrically connected between the input terminal and a radio frequency terminal, the balun having an inductance that compensates for a loss of the input matching inductor.

7. The wireless communication device of claim 1 wherein the low noise amplifier further includes a second gain circuit electrically connected between the input terminal and the output terminal in parallel with the first gain circuit, the second gain circuit operable to provide inverting amplification to the radio frequency input signal in a second gain mode of the plurality of modes.

8. The wireless communication device of claim 1 wherein the balun includes a primary winding and a secondary winding, the primary winding and the secondary winding connected to ground on opposite ends relative to one another such that the balun provides the inversion to the radio frequency input signal.

9. A low noise amplifier comprising:

a mode control circuit configured to operate the low noise amplifier in a selected mode chosen from a plurality of modes including a first gain mode and a bypass mode;

a first gain circuit electrically connected between an input terminal configured to receive a radio frequency input signal and an output terminal configured to provide a radio frequency output signal, the first gain circuit operable to provide inverting amplification to the radio frequency input signal in the first gain mode; and

a bypass circuit electrically connected in parallel with the first gain circuit between the input terminal and the output terminal, the bypass circuit including a balun operable to provide an inversion to the radio frequency input signal in the bypass mode so as to compensate for a difference in phase delay between the bypass circuit and the first gain circuit.

10. The low noise amplifier of claim 9 further comprising a phase compensation circuit electrically connected to the output terminal and configured to further compensate for the difference in phase delay.

11. The low noise amplifier of claim 10 wherein the phase compensation circuit includes a plurality of capacitors that are digitally selectable.

12. The low noise amplifier of claim 10 further comprising a serial interface configured to receive data operable to control an amount of phase adjustment provided by the phase compensation circuit.

13. The low noise amplifier of claim 10 wherein the balun is operable to provide a coarse phase adjustment and the phase compensation circuit is operable to provide a fine phase adjustment.

14. The low noise amplifier of claim 9 further comprising an input matching inductor electrically connected between the input terminal and a radio frequency terminal, the balun having an inductance that compensates for a loss of the input matching inductor.

15. The low noise amplifier of claim 9 wherein the mode control circuit is operable to select the bypass circuit and deselect the first gain circuit in the bypass mode, and to select the first gain circuit and deselect the bypass circuit in the first gain mode.

16. The low noise amplifier of claim 9 further comprising a second gain circuit electrically connected between the input terminal and the output terminal in parallel with the first gain circuit, the second gain circuit operable to provide inverting amplification to the radio frequency input signal in a second gain mode of the plurality of modes.

17. The low noise amplifier of claim 9 wherein the balun includes a primary winding and a secondary winding, the primary winding and the secondary winding connected to ground on opposite ends relative to one another such that the balun provides the inversion to the radio frequency input signal.

18. A radio frequency front-end system comprising:

a low noise amplifier including a mode control circuit configured to operate the low noise amplifier in a selected mode chosen from a plurality of modes including a first gain mode and a bypass mode, a first gain circuit electrically connected between an input terminal and an output terminal and operable to provide inverting amplification to a radio frequency input signal received at the input terminal in the first gain mode, and a bypass circuit electrically connected in parallel with the first gain circuit between the input terminal and the output terminal, the bypass circuit including a balun operable to provide an inversion to the radio frequency input signal in the bypass mode so as to compensate for a difference in phase delay between the bypass circuit and the first gain circuit; and

an input switch including a first throw operable to provide the radio frequency input signal to the input terminal of the low noise amplifier.

19. The radio frequency front-end system of claim 18 wherein the low noise amplifier further includes a phase compensation circuit electrically connected to the output terminal and configured to further compensate for the difference in phase delay.

20. The radio frequency front-end system of claim 19 wherein the balun is operable to provide a coarse phase adjustment and the phase compensation circuit is operable to provide a fine phase adjustment.