Patent Application
20170093226
This application claims priority to Indian patent application no. 5114/CHE/2015 filed on Sep. 24, 2015, the complete disclosure of which, in its entirely, is herein incorporated by reference.
Technical Field
The embodiments herein generally relate to voltage regulation, and more particularly, to a circuit and a method for regulating voltage of a high radio frequency line of a radio frequency circuit for the protection of devices that are driven by the high radio frequency line in integrated circuits.
Description of the Related Art
In communication systems, transmission line is configured to carry alternating current of a radio frequency that includes signals with a high radio frequency. Typically, the transmission lines are used for purposes such as connecting a radio transmitter and a radio receiver with their antenna, distributing cable television signals, routing calls between telephone switching centers, computer network connections and high speed computer data buses and the like. However, inside integrated circuits (ICs), distances between source and destination of the radio frequency signals are typically much lower than wavelength of the radio frequency signals. In such cases, a lumped model of interconnect consisting of series inductor and a shunt load capacitor describes the behavior of interconnect accurately. In such interconnects, when the frequency of an input signal is close to resonant frequency of a LC network, gain of the circuit is very large. During such instances, the interconnect produces an amplified version of the input signal at output, which may not desirable in cases where the output of the interconnect feeds circuits that have devices voltage rating at their inputs.
Accordingly, there remains a need for a system and a method to monitor and regulate voltage across a low voltage device driven by a long line carrying radio frequency signals in integrated circuits.
In view of a foregoing, an embodiment herein provides a circuit for regulating a voltage of a high radio frequency line across a low voltage device. The circuit includes an input port, a high radio frequency line, a LC circuit, a peak detection circuit, a comparator, and a variable resistor. The input port receives a high radio frequency signal. The high radio frequency line is configured to carry the high radio frequency signal from the input port. The LC circuit is configured to boost the high radio frequency line into a boosted high radio frequency line. The peak detection circuit is configured to (i) measure a voltage of the boosted high radio frequency line, and (ii) detect a peak of the voltage of the boosted high radio frequency line. The comparator is configured to compare the voltage of the boosted high radio frequency line with a pre-defined voltage. The variable resistor is configured to control quality factor of the circuit to gain voltage. The variable resistor regulates the voltage of the boosted high radio frequency line to equal to the pre-defined voltage by adjusting a resistance of the variable resistor based on an output of the comparator.
In an embodiment, the LC circuit includes an inductor, and a capacitor. The inductor is configured to model an inductance of the high radio frequency line. The capacitor is configured to model a capacitance of the high radio frequency line to obtain the boosted high radio frequency line.
In another embodiment, the voltage that is regulated is applied to the low voltage device.
In yet another embodiment, the comparator identifies a voltage variation between the pre-defined voltage and the voltage of the boosted high radio frequency line.
In yet another embodiment, the variable resistor is placed in series with the high radio frequency line.
In one aspect, a circuit for regulating a voltage of a high radio frequency line across a low voltage device is provided. The circuit includes an input port, a high radio frequency line, a LC circuit, a peak detection circuit, a comparator, and a variable resistor. The input port receives a high radio frequency signal. The high radio frequency line is configured to carry the high radio frequency signal from the input port. The LC circuit is configured to boost the high radio frequency line into a boosted high radio frequency line. The LC circuit includes an inductor, and a capacitor. The inductor is configured to model an inductance of the high radio frequency line. The capacitor is configured to model a capacitance of the high radio frequency line to obtain the boosted high radio frequency line.
The peak detection circuit is configured to (i) measure a voltage of the boosted high radio frequency line, and (ii) detect a peak of the voltage of the boosted high radio frequency line. The comparator is configured to compare the voltage of the boosted high radio frequency line with a pre-defined voltage. The comparator identifies a voltage variation between the pre-defined voltage and the voltage of the boosted high radio frequency line. The variable resistor is configured to control quality factor of the circuit to gain voltage. The variable resistor regulates the voltage of the boosted high radio frequency line to equal to the pre-defined voltage by adjusting a resistance of the variable resistor based on the voltage variation identified by the comparator. The voltage is regulated is applied to the low voltage device. The variable resistor is placed in series with the high radio frequency line.
In an embodiment, the resistance of the variable resistor that is required to regulate the voltage of the high radio frequency line is determined based on a known input frequency of the high radio frequency line.
In another embodiment, the resistance of the variable resistor is selected from a look up table. The look up table may be generated during an initial calibration based on a known input frequency.
In yet another embodiment, the variable resistor is placed in series with the inductor.
In another aspect, a method for regulating a voltage of a high radio frequency line across a low voltage device is provided. The method includes the following steps: (a) applying a high radio frequency signal to an input port of a high radio frequency line, wherein the high radio frequency is configured to carry the high radio frequency signal; (b) boosting, using a LC circuit, the high radio frequency line into a boosted high radio frequency line; (c) measuring, using a peak detection circuit, a voltage of the boosted high radio frequency line; (d) detecting, using the peak detection circuit, a peak of the voltage of the boosted high radio frequency line; (e) comparing, using a comparator, the voltage of the boosted high radio frequency line with a pre-defined voltage; (f) regulating, using a variable resistor, the voltage of the boosted high radio frequency line to equal to the pre-defined voltage by adjusting a resistance of the variable resistor based on an output of the comparator; and (g) applying the voltage that is regulated to the low voltage device.
These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which:
The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
Various embodiments provide circuits and methods to regulate voltage across load resistor of a high radio frequency transmission line of a radio frequency (RF) circuit. More particularly, the circuits and methods disclosed herein deals with the sensing and regulation of the voltage at the output port of interconnect to protect low voltage devices connected to a port.
As mentioned, there remains a need for a circuit and a method to monitor and regulate voltage across a low voltage device driven by a long line carrying radio frequency signals in integrated circuits. Referring now to the drawings, and more particularly to
At step 212, the voltage of the boosted high radio frequency line is regulated to equal to the pre-defined voltage 114 by adjusting a resistance of the variable resistor 106 based on an output of the comparator 110 using a variable resistor 106. The resistance of the circuit may affect quality factor (e.g. Q factor) of the circuit and reduce the gain from the input of the high radio frequency line to its output. The variable resistor 106 will adjust the resistance continuously till the voltage of the boosted high radio frequency line is equal to the pre-defined voltage 114. In one embodiment, if the voltage of the boosted high radio frequency line is higher than the pre-defined voltage 114, the variable resistor 106 decrease the resistance based on an output of the comparator 110. In another embodiment, if the voltage of the boosted high radio frequency line is lower than the pre-defined voltage 114, the variable resistor 106 increase the resistance based on the output of the comparator 110. The output of the comparator 110 may include voltage variation between the pre-defined voltage 114 and the voltage of the boosted high radio frequency line. At step 214, the voltage that is regulated is applied to the low voltage device 112.
The circuit protects the low voltage device 112 that has a low voltage rating from the voltage of the boosted high radio frequency line. The circuit regulates the voltage of the boosted high radio frequency line to equal to the pre-defined voltage 114 by varying the resistance of the variable resistor 106, thereby a regulated voltage is supplied to the low voltage device 112. The circuit is uncomplicated design compared to existing circuits.
The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein may be practiced with modification within the spirit and scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 5114/CHE/2015 | Sep 2015 | IN | national |
