State change stabilization in a phase shifter/attenuator circuit

Patent metadata

Field	Value
Publication number	US-10069481-B2
Application number	US-201715839676-A
Country	US
Kind code	B2
Filing date	Dec 12, 2017
Priority date	Jun 26, 2015
Publication date	Sep 4, 2018
Grant date	Sep 4, 2018

Abstract

An electronic system that includes a digitally selectable phase shifter circuit and an insertion loss fine adjustment circuit such that the system as a whole exhibits little or no change in insertion loss when changing phase state, and/or a digitally selectable attenuator circuit and a phase fine adjustment circuit such that the system as a whole exhibits little or no effect on phase when changing attenuation state. Included are methods for selecting adjustment control words for such circuits.

First claim

What is claimed is:

1. An electronic circuit for modifying an applied radio frequency, including:
(a) at least one of (1) a phase shifter circuit for modifying the phase of the applied radio frequency signal in response to applied phase state digital control words, and (2) an attenuator circuit for selectively attenuating the applied radio frequency signal in response to applied attenuation state digital control words;
(b) a fine adjustment circuit coupled to at least one of the phase shifter circuit and the attenuator circuit, the fine adjustment circuit including at least one of (1) an adjustment attenuator circuit for providing a selectable attenuation adjustment as a function of the applied phase state digital control words to substantially equalize insertion loss variations between phase states selected by the applied phase state digital control words, and (2) an adjustment phase shifter circuit for providing a selectable phase shift adjustment as a function of the applied attenuation state digital control words to substantially equalize phase variations between attenuation states selected by the applied attenuation digital control words; and
(c) an adjustment control circuit coupled to the fine adjustment circuit, wherein the adjustment control circuit includes a look-up table that maps at least one of the applied phase state digital control words or the applied attenuation state digital control words to at least one set of adjustment digital control words, and wherein at least one set of the adjustment digital control words is coupled to the fine adjustment circuit.

2. The invention of claim 1 , wherein the adjustment control circuit is coupled to an external source of adjustment digital control words, and further includes a multiplexer for selectably applying adjustment digital control words to the fine adjustment circuit from one of the look-up table or the external source of adjustment digital control words.

3. The invention of claim 1 , wherein the look-up table includes multiple pages of memory locations, each of which maps at least one of the applied phase state digital control words or the applied attenuation state digital control words to a separate set of adjustment digital control words.

4. The invention of claim 1 , wherein at least one of the at least one attenuator circuit includes a plurality of selectable attenuator circuits for providing selectable attenuation as a function of the applied phase state digital control words.

5. The invention of claim 1 , wherein at least one of the at least one phase shifter circuit includes a plurality of selectable phase shifter circuits for providing selectable phase shift adjustment as a function of the applied attenuation digital control words.

6. The invention of claim 1 , wherein the step size of the attenuation adjustment provided by the adjustment attenuator circuit is less than about 0.5 dB.

7. The invention of claim 1 , wherein the step size of the phase shift provided by the adjustment phase shifter circuit is less than or equal to about 2.5 degrees of phase.

8. An electronic circuit for modifying an applied radio frequency, including:
(a) at least one phase shifter circuit for modifying the phase of the applied radio frequency signal in response to applied phase state digital control words; and
(b) a fine adjustment circuit coupled to at least one of the at least one phase shifter circuit, the fine adjustment circuit including at least one attenuator circuit for providing a selectable attenuation adjustment as a function of the applied phase state digital control words to substantially equalize insertion loss variations between phase states selected by the applied phase state digital control words; and
(c) an adjustment control circuit coupled to the fine adjustment circuit, wherein the adjustment control circuit includes a look-up table that maps the applied phase state digital control words to at least one set of adjustment digital control words, and wherein at least one set of the adjustment digital control words is coupled to the fine adjustment circuit.

9. The invention of claim 8 , wherein the adjustment control circuit is coupled to an external source of adjustment digital control words, and further includes a multiplexer for selectably applying adjustment digital control words to the fine adjustment circuit from one of the look-up table or the external source of adjustment digital control words.

10. The invention of claim 8 , wherein the look-up table includes multiple pages of memory locations, each of which maps the applied phase state digital control words to a separate set of adjustment digital control words.

11. The invention of claim 8 , wherein at least one of the at least one attenuator circuit includes a plurality of selectable attenuator circuits for providing selectable attenuation as a function of the applied phase state digital control words.

12. The invention of claim 8 , further including at least one attenuator circuit, coupled to the adjustment control circuit, for selectively attenuating the applied radio frequency signal in response to applied attenuation state digital control words.

13. The invention of claim 8 , wherein the step size of the attenuation adjustment provided by the fine adjustment circuit is less than about 0.5 dB.

14. An electronic circuit for modifying an applied radio frequency, including:
(a) at least one attenuator circuit for selectively attenuating the applied radio frequency signal in response to applied attenuation state digital control words; and
(b) a fine adjustment circuit coupled to at least one of the at least one attenuator circuit, the fine adjustment circuit including at least one phase shifter circuit for providing a selectable phase shift adjustment as a function of the applied attenuation state digital control words to substantially equalize phase variations between attenuation states selected by the applied attenuation digital control words; and
(c) an adjustment control circuit coupled to the fine adjustment circuit, wherein the adjustment control circuit includes a look-up table that maps the applied attenuation state digital control words to at least one set of adjustment digital control words, and wherein at least one set of the adjustment digital control words is coupled to the fine adjustment circuit.

15. The invention of claim 14 , wherein the adjustment control circuit is coupled to an external source of adjustment digital control words, and further includes a multiplexer for selectably applying adjustment digital control words to the fine adjustment circuit from one of the look-up table or the external source of adjustment digital control words.

16. The invention of claim 14 , wherein the look-up table includes multiple pages of memory locations, each of which maps the applied attenuation state digital control words to a separate set of adjustment digital control words.

17. The invention of claim 14 , wherein at least one of the at least one phase shifter circuit includes a plurality of selectable phase shifter circuits for providing selectable phase shift adjustment as a function of the applied attenuation state digital control words.

18. The invention of claim 14 , further including at least one phase shifter circuit, coupled to the adjustment control circuit, for modifying the phase of the applied radio frequency signal in response to applied phase state digital control words.

19. The invention of claim 14 , wherein the step size of the phase shift adjustment provided by the fine adjustment circuit is l

Assignees

• Psemi Corp

Inventors

• Allison Matt
• Shapiro Eric S

Classifications

• H03H11/24

  Frequency-independent attenuators · CPC title

• H03H11/20 Primary

  Two-port phase shifters providing an adjustable phase shift · CPC title

• H03K2005/00286

  Phase shifter, i.e. the delay between the output and input pulse is dependent on the frequency, and such that a phase difference is obtained independent of the frequency · CPC title

• H03K5/08

  by limiting; by thresholding; by slicing, i.e. combined limiting and thresholding (H03K5/07 takes precedence; comparing one pulse with another H03K5/22; providing a determined threshold for switching H03K17/30) · CPC title

• H03H7/25

  comprising an element controlled by an electric or magnetic variable (H03H7/27 takes precedence) · CPC title