Mismatch detection using replica circuit

Patent metadata

Field	Value
Publication number	US-11519956-B2
Application number	US-202017003498-A
Country	US
Kind code	B2
Filing date	Aug 26, 2020
Priority date	May 7, 2014
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

An apparatus for detecting difference in operating characteristics of a main circuit by using a replica circuit is presented. In one exemplary case, a sensed difference in operating characteristics of the two circuits is used to drive a tuning control loop to minimize the sensed difference. In another exemplary case, several replica circuits of the main circuit are used, where each is isolated from one or more operating variables that affect the operating characteristic of the main circuit. Each replica circuit can be used for sensing a different operating characteristic, or, two replica circuits can be combined to sense a same operating characteristic.

First claim

What is claimed is:

1. A method for operating a first radio frequency (RF) circuit path comprising a first active circuit, the method comprising:
providing a second RF circuit path comprising a second active circuit that is a reduced size replica of the first active circuit;
sensing a difference between one or more operating characteristics of the first RF circuit path, sensed at one or more sensing points of the first RF circuit path, and one or more reference operating characteristics of the second RF circuit path, sensed at one or more sensing points of the second RF circuit path; and
controlling operation of the first RF circuit path based on the sensing,
wherein,
the one or more operating characteristics of the first RF circuit path are affected by a set of operating variables, and
the second RF circuit path is configured so that one or more reference operating characteristics of the second RF circuit path are substantially isolated from a subset of the operating variables.

2. A method for operating a first radio frequency (RF) circuit path comprising a first active circuit, the method comprising:
providing a second RF circuit path comprising a second active circuit that is a reduced size replica of the first active circuit;
coupling one or more sensing points of the first RF circuit path to a sensing circuit;
coupling one or more sensing points of the second RF circuit path to the sensing circuit;
based on the couplings, sensing a difference between one or more operating characteristics of the first RF circuit path, sensed at the one or more sensing points of the first RF circuit path, and one or more reference operating characteristics of the second RF circuit path, sensed at the one or more sensing points of the second RF circuit path; and
controlling operation of the first RF circuit path based on the sensing,
wherein,
the one or more operating characteristics of the first RF circuit path are affected by a set of operating variables, and
the second RF circuit path is configured so that one or more reference operating characteristics of the second RF circuit path are substantially isolated from a subset of the operating variables.

3. The method according to claim 1 , wherein the set of operating variables comprises variables selected from the group consisting of: a) a load to the first/second RF circuit paths, b) a local temperature at the first/second active circuits, c) hot carrier injection (HCI) effect on devices of the first/second active circuits, d) transient effects on the first/second active circuits, e) floating body effects on devices of the first/second active circuits, f) different operating modes of the first/second RF circuit paths, g) different frequencies of operation of the first/second RF circuit paths, and combinations thereof.

4. The method according to claim 1 , further comprising:
monolithically integrating the first and second RF circuit paths;
based on the integrating, placing the second active circuit away from the first active circuit; and
based on the placing, thermally isolating the second active circuit from the first active circuit,
wherein controlling operation of the first RF circuit path based on the sensing comprises:
based on the thermally isolating, controlling a gain of the first active circuit according to a sensed difference in gains of the first active circuit and the second active circuit.

5. The method according to claim 4 , wherein the first active circuit is selected from the group consisting of: a) an amplifier circuit, b) a power amplifier, c) a low noise amplifier (LNA), d) a mixer, e) a voltage controlled oscillator (VCO), f) a modulator, and g) a demodulator.

6. The method according to claim 4 , wherein:
the controlling of the gain of the first active circuit provides gain stabilization of the first RF circuit path.

7. The method according to claim 4 , wherein the controlling of the gain is selected from the group consisting of: a) controlling bias voltages, b) controlling input signal levels to the first and/or the second active circuit, c) controlling output signal levels from the first and/or the second active circuit, and combinations thereof.

8. The method according to claim 4 , further comprising:
based on the integrating, providing a temperature sensor at a vicinity of the second active circuit;
based on the providing, sensing a temperature of the second active circuit; and
based on the sensing, controlling the gain of the second active circuit.

9. The method according to claim 1 , further comprising:
monolithically integrating the first and second RF circuit paths;
activating the second active circuit prior to activation of the first active circuit;
based on the activating, removing transient and/or floating body effects from the second active circuit;
based on the removing, providing a stable operation of the second RF circuit path; and
activating the first active circuit;
wherein controlling operation of the first RF circuit path based on the sensing comprises:
sensing a difference between one or more operating characteristics of the first RF circuit path and the second RF circuit path; and
based on the sensing, controlling the first RF circuit path to affect the one or more operating characteristics of the first RF circuit path.

10. The method according to claim 9 , wherein:
the sensed difference comprises a value selected from the group consisting of: a) a biasing voltage, b) an output voltage, c) a gain, and combinations thereof, and
the controlling of the first RF circuit path provides compensation of transient and/or floating body effects of the first RF circuit path.

11. The method according to claim 1 , further comprising:
designing the second active circuit for reduced stress;
based on the designing, monolithically integrating the first and second RF circuit paths; and
based on the designing, reducing hot carrier injection (HCI) effects over the second active circuit;
wherein controlling operation of the first RF circuit path based on the sensing comprises:
based on the reducing, controlling biasing to the first active circuit according to a sensed difference in biasing voltages of the first active circuit and the second active circuit, thereby compensating HCI effects over the first RF circuit path.

12. The method according to claim 11 , wherein the designing of the second active circuit comprises designing for features selected from the group consisting of: a) a different stack height, b) a different device width, c) a different device length, d) an input signal scaling, e) an output signal scaling, f) a different supply voltage, and combinations thereof.

13. The method according to claim 1 , further comprising:
monolithically integrating the first and second RF circuit paths;
terminating the second RF circuit path at an output node of the second RF circuit path using a broadband load; and
configuring the first RF circuit path for operation in a selected operating frequency of the plurality of operating frequencies;
wherein controlling operation of the first RF circuit path based on the sensing comprises:
sensing a difference between one or more operating characteristics of the first RF circuit path and the second RF circuit path; and
based on the sensing, controlling the first RF circuit path for reducing the difference, wherein the sensed difference comprises a value selected from the group consisting of: a) a biasing voltage, b) an output voltage, c) a gain, d) an output impedance, e) an input impedance, and combinations thereof.

14. The method according to claim 13 , wherein the controlli

Assignees

• Psemi Corp

Inventors

• Nobbe Dan William
• Reedy Ronald Eugene
• Bacon Peter
• Cable James S

Classifications

• H03F2203/21142

  Output signals of a plurality of power amplifiers are parallel combined to a common output · CPC title

• H03F3/195

  in integrated circuits · CPC title

• H03F2200/378

  A variable capacitor being added in the output circuit, e.g. collector, drain, of an amplifier stage · CPC title

• H03F1/56 Primary

  Modifications of input or output impedances, not otherwise provided for · CPC title

• G01R31/2836

  Fault-finding or characterising (G01R31/2822 - G01R31/2831 take precedence) · CPC title