Breakdown protection circuit for power amplifier
阅读说明:本技术 用于功率放大器的击穿保护电路 (Breakdown protection circuit for power amplifier ) 是由 M·M·R·艾斯梅尔 于 2019-08-06 设计创作,主要内容包括:本公开涉及用于功率放大器的击穿保护电路。公开了用于提高放大器的可靠性和/或减少或防止放大器的击穿(特别是放大器的晶体管的击穿)的系统、方法和设备。保护电路可以电耦合到放大器,并且可以配置成减少放大器处的电压摆动。放大器可以包括第一晶体管,并且保护电路可以包括电耦合到放大器的第一晶体管的控制端子的第二晶体管。当保护电路的第二晶体管的控制端子处的电源满足阈值功率时,保护电路可以配置为降低放大器的第一晶体管的电源端子处的功率。通过降低放大器的第一晶体管的电源端处的电压,保护电路可以允许放大器安全地操作,而不会发生击穿。(The present disclosure relates to a breakdown protection circuit for a power amplifier. Systems, methods, and apparatus are disclosed for improving the reliability of an amplifier and/or reducing or preventing breakdown of an amplifier, particularly breakdown of transistors of the amplifier. The protection circuit may be electrically coupled to the amplifier and may be configured to reduce a voltage swing at the amplifier. The amplifier may include a first transistor, and the protection circuit may include a second transistor electrically coupled to a control terminal of the first transistor of the amplifier. The protection circuit may be configured to reduce power at the power supply terminal of the first transistor of the amplifier when the power supply at the control terminal of the second transistor of the protection circuit satisfies the threshold power. By reducing the voltage at the power supply terminal of the first transistor of the amplifier, the protection circuit may allow the amplifier to operate safely without breakdown.)
1. An apparatus, comprising:
an amplifier; and
a protection circuit electrically coupled to the control terminal of the amplifier, the protection circuit configured to reduce a voltage swing at the amplifier based at least in part on a presence of a threshold power at the control terminal of the amplifier or at a power supply terminal of the amplifier.
2. The device of claim 1, wherein to reduce voltage swing at the amplifier, the protection circuit is configured to reduce a voltage at a power supply terminal of the amplifier.
3. The apparatus of claim 1, wherein the amplifier comprises a transistor, wherein the control terminal comprises a control terminal of the transistor, and wherein the power supply terminal comprises a power supply terminal of the transistor.
4. The apparatus of claim 3, wherein the transistor comprises a Complementary Metal Oxide Semiconductor (CMOS) transistor, wherein the voltage swing comprises a voltage swing between a drain of the CMOS transistor and a source of the CMOS transistor.
5. The apparatus of claim 3, wherein the protection circuit comprises a transistor, wherein a control terminal of the transistor of the protection circuit is electrically coupled to a control terminal of the transistor of the amplifier.
6. The apparatus of claim 5, wherein a power supply terminal of a transistor of the protection circuit is electrically coupled to a power supply terminal of a transistor of the amplifier.
7. The apparatus of claim 6, wherein the protection circuit further comprises at least one of:
a first sensing element electrically coupled between a control terminal of a transistor of the protection circuit and a control terminal of a transistor of the amplifier; or
A second sensing element electrically coupled between a power supply terminal of the transistor of the protection circuit and a power supply terminal of the transistor of the amplifier.
8. The device of claim 7, wherein at least one of the first sensing element or the second sensing element comprises one or more of a capacitor, a resistor, an inductor, a diode, a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), a Bipolar Junction Transistor (BJT), a transmission line, or a coupler.
9. The apparatus of claim 1, wherein the amplifier includes a first transistor and a second transistor arranged in a stack such that a power supply terminal of the first transistor is electrically coupled to a power supply terminal of the second transistor, and wherein the control terminal comprises a control terminal of the first transistor.
10. The apparatus of claim 9, wherein the protection circuit comprises a first transistor and a second transistor arranged in a stack such that a power supply terminal of the first transistor of the protection circuit is electrically coupled to a power supply terminal of the second transistor of the protection circuit, wherein:
a control terminal of the first transistor of the protection circuit is electrically coupled to a control terminal of the first transistor of the amplifier,
a power supply terminal of the first transistor of the protection circuit is electrically coupled to a power supply terminal of the first transistor of the amplifier,
a control terminal of the second transistor of the protection circuit is electrically coupled to a control terminal of the second transistor of the amplifier, an
A power supply terminal of the first transistor of the protection circuit is electrically coupled to a power supply terminal of the first transistor of the amplifier.
11. A protection circuit configured to prevent amplifier breakdown, the protection circuit comprising:
a first sensing element; and
a first transistor comprising a control terminal electrically coupled to a control terminal of a second transistor of the amplifier through the first sensing element,
wherein the protection circuit is configured to reduce a voltage swing at a power supply terminal of the amplifier based at least in part on a presence of threshold power at a control terminal of the first transistor.
12. The protection circuit of claim 11, further comprising a second sensing element, wherein the first transistor includes a power supply terminal electrically coupled to a control terminal of the second transistor through the second sensing element.
13. The protection circuit of claim 12, wherein the power supply terminal of the second transistor is a first power supply terminal, wherein the second transistor includes a second power supply terminal, wherein the amplifier includes a third transistor arranged in stack with the second transistor such that the second power supply terminal of the second transistor is electrically coupled to the power supply terminal of the third transistor, the protection circuit further comprising:
a fourth transistor including a control terminal electrically coupled to a control terminal of the third transistor.
14. The protection circuit of claim 13, wherein the power supply terminal of the first transistor is a first power supply terminal of the first transistor, wherein the fourth transistor includes a power supply terminal electrically coupled to a second power supply terminal of the first transistor.
15. The protection circuit of claim 14, wherein the first transistor comprises a third Complementary Metal Oxide Semiconductor (CMOS) transistor, wherein the third transistor comprises a third CMOS transistor, wherein the control terminal of the first CMOS transistor comprises a gate terminal of the first CMOS transistor, wherein the first power supply terminal of the first CMOS transistor comprises a drain terminal of the first CMOS transistor, wherein the second power supply terminal of the first CMOS transistor comprises a source terminal of the first CMOS transistor, wherein the control terminal of the third CMOS transistor comprises a gate terminal of the third CMOS transistor, wherein the power supply terminal of the third CMOS transistor comprises a drain terminal of the third CMOS transistor.
16. The protection circuit of claim 11, wherein the first transistor comprises a Complementary Metal Oxide Semiconductor (CMOS) transistor, wherein the control terminal comprises a gate terminal of the CMOS transistor.
17. A system, comprising:
an amplifier; and
a protection circuit electrically coupled to the control terminal of the amplifier, the protection circuit configured to reduce a voltage swing at the amplifier based at least in part on a presence of a threshold power at the control terminal of the amplifier or at a power supply terminal of the amplifier.
18. The system of claim 17, wherein to reduce voltage swing at the amplifier, the protection circuit is configured to reduce a voltage at a power supply terminal of the amplifier.
19. The system of claim 17, wherein the amplifier comprises a Complementary Metal Oxide Semiconductor (CMOS) transistor, wherein the control terminal comprises a gate terminal of the CMOS transistor, and wherein the power supply terminal comprises a drain terminal of the CMOS transistor, wherein the voltage swing comprises a voltage swing between the drain terminal of the CMOS transistor and a source terminal of the CMOS transistor.
20. The system of claim 19, wherein the protection circuit comprises a CMOS transistor, wherein a gate terminal of the CMOS transistor of the protection circuit is electrically coupled to a gate terminal of the transistor of the amplifier through a first sensing element, wherein a drain terminal of the CMOS transistor of the protection circuit is electrically coupled to a drain terminal of the CMOS transistor of the amplifier through a second sensing element.
Technical Field
The present disclosure relates to improving the reliability of amplifiers, and more particularly to techniques for reducing or avoiding breakdown of transistors in amplifiers.
Background
Traditionally, Power Amplifier (PA) designs have been dominated by gallium nitride (GaN), gallium arsenide (GaAs), or silicon germanium (SiGe). However, the ever-increasing demand for higher integration and lower cost of mobile communication devices has led to a trend towards using cheaper technologies in PA design, which leads to significant PA reliability issues.
Disclosure of Invention
The innovations described in the claims each have several aspects, no single one of which is solely responsible for the desirable attributes. Without limiting the scope of the claims, some of the salient features of the disclosure will now be briefly described.
The invention enables an improved protection of the amplifier, increasing the reliability of the amplifier by preventing or reducing the breakdown of the amplifier. An apparatus according to the present disclosure may include an amplifier and a protection circuit. The protection circuit may be electrically coupled to the control terminal of the amplifier. The protection circuit may be configured to reduce voltage swing at the amplifier. The reduction of the voltage swing may be based at least in part on detection of a threshold power at a control terminal of the amplifier.
The apparatus of the previous paragraph can also include any combination of the following features described in this paragraph, as well as other features described herein. The protection circuit may also be electrically coupled to the power supply terminal of the amplifier. The amplifier may comprise a transistor and the control terminal may comprise a control terminal of the transistor of the amplifier. The protection circuit may include a transistor corresponding to a transistor of the amplifier. The control terminal of the transistor of the protection circuit may be electrically coupled to the control terminal of the transistor of the amplifier. The protection circuit may also include one or more sensing elements. The one or more sensing elements may be electrically coupled between a control terminal of a transistor of the protection circuit and a control terminal of a transistor of the amplifier. Any of the one or more sensing elements may include one or more of a capacitor, a resistor, an inductor, a diode, a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), a Bipolar Junction Transistor (BJT), a transmission line, or a coupler.
The apparatus of any of the preceding paragraphs may also include any combination of the following features described in this paragraph, as well as other features described herein. The power supply terminal of the transistor of the protection circuit may be electrically coupled to the power supply terminal of the transistor of the amplifier. The protection circuit may also include one or more sensing elements. The one or more sensing elements may be electrically coupled between a power supply terminal of a transistor of the protection circuit and a power supply terminal of a transistor of the amplifier. Any of the one or more sensing elements may include one or more of a capacitor, a resistor, an inductor, a diode, a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), a Bipolar Junction Transistor (BJT), a transmission line, or a coupler.
The apparatus of any of the preceding paragraphs may also include any combination of the following features described in this paragraph, as well as other features described herein. The transistor of the amplifier may be a first transistor, and the amplifier may include a second transistor. The protection circuit may be electrically coupled to a control terminal of the second transistor of the amplifier. The first power supply terminal of the second transistor of the amplifier may be electrically coupled to the second power supply terminal of the first transistor of the amplifier. The second power supply terminal of the first transistor of the amplifier may be different from the first power supply terminal of the first transistor and/or may be different from the control terminal of the first transistor. The transistor of the protection circuit may be a first transistor of the protection circuit. The protection circuit may include a second transistor. In some cases, the protection circuit includes a replica circuit corresponding to the amplifier circuit. The replica circuit may comprise one or more transistors, which match or correspond to one or more transistors of the amplifier, which may comprise at least a first transistor of the amplifier or a second transistor of the amplifier. The replica circuit may be configured to compensate for variations in at least one of process, voltage and/or temperature of one or more transistors of the amplifier.
The apparatus of any of the preceding paragraphs may also include any combination of the following features described in this paragraph, as well as other features described herein. To reduce voltage swing at the amplifier, the protection circuit may be configured to reduce the voltage at the power supply terminal of the amplifier. Any of the transistors described herein may include a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). The first power supply terminal, the control terminal, and the second power supply terminal of any of the transistors described herein may correspond to a drain terminal, a gate terminal, and a source terminal, respectively, of a MOSFET. The first power supply terminal, the control terminal, and the second power supply terminal of any of the transistors described herein may correspond to a source terminal, a gate terminal, and a drain terminal, respectively, of a MOSFET. The voltage swing may be a voltage swing between a power supply terminal and another power supply terminal (e.g., between a first power supply terminal and a second power supply terminal), or between a power supply terminal and a control terminal. For example, the voltage swing may be a voltage swing between the drain of the MOSFET and the source of the MOSFET, a voltage swing between the drain of the MOSFET and the gate of the MOSFET, or a voltage swing between the source of the MOSFET and the gate of the MOSFET. Any of the transistors described herein may comprise a Complementary Metal Oxide Semiconductor (CMOS).
The apparatus of any of the preceding paragraphs may also include any combination of the following features described in this paragraph, as well as other features described herein. Any of the transistors described herein may include a Bipolar Junction Transistor (BJT). The first power supply terminal, the control terminal, and the second power supply terminal of any transistor described herein may correspond to an emitter terminal, a base terminal, and a collector terminal, respectively, of a BJT. The first power supply terminal, the control terminal, and the second power supply terminal of any of the transistors described herein may correspond to a collector terminal, a base terminal, and an emitter terminal, respectively, or a BJT. The voltage swing may be a voltage swing between a power supply terminal and another power supply terminal (e.g., between a first power supply terminal and a second power supply terminal), or between a power supply terminal and a control terminal. For example, the voltage swing may be a voltage swing between an emitter of the BJT and a collector of the BJT, a voltage swing between an emitter of the BJT and a base of the BJT, or a voltage swing between a collector of the BJT and a base of the BJT.
The present invention provides an improved protection circuit for an amplifier that can improve the reliability of the amplifier and prevent or reduce the breakdown of the amplifier. The protection circuit according to the present disclosure may be configured to reduce voltage swing at the amplifier. The protection circuit may include at least a first transistor and a second transistor. The first transistor of the protection circuit may include a first power supply terminal, a control terminal, and a second power supply terminal. The first power supply terminal of the first transistor of the protection circuit may be electrically coupled to the first power supply terminal of the first transistor of the amplifier through the first sensing element. The first control terminal of the first transistor of the protection circuit may be electrically coupled to the control terminal of the first transistor of the amplifier through the second sensing element. The second transistor of the protection circuit may include a first power supply terminal, a control terminal, and a second power supply terminal. The second power supply terminal of the second transistor of the protection circuit may be electrically coupled to the second power supply terminal of the first transistor of the protection circuit. The second power supply terminal of the first transistor of the protection circuit may be different from the first power supply terminal of the first transistor of the protection circuit. The second power supply terminal of the first transistor of the protection circuit may be different from the control terminal of the first transistor of the protection circuit. A control terminal of the second transistor of the protection circuit may be electrically coupled to a control terminal of the second transistor of the amplifier through a third sensing element. The protection circuit may be configured to reduce voltage swing at the amplifier. The reduction in the voltage swing may be based at least in part on a voltage at a control terminal of a first transistor of the amplifier or a voltage at a control terminal of a second transistor of the amplifier.
The protection circuit of the preceding paragraph can also include any combination of the following features described in this paragraph, as well as other features described herein. Any one of the first transistor of the protection circuit, the second transistor of the protection circuit, the first transistor of the amplifier, or the second transistor of the amplifier may include a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). The first power supply terminal, the control terminal, and the second power supply terminal of any of the transistors described herein may correspond to a drain terminal, a gate terminal, and a source terminal, respectively, of a MOSFET. The first power supply terminal, the control terminal, and the second power supply terminal of any of the transistors described herein may correspond to a source terminal, a gate terminal, and a drain terminal, respectively, of a MOSFET. Any one of the first transistor of the protection circuit, the second transistor of the protection circuit, the first transistor of the amplifier, or the second transistor of the amplifier may include a Complementary Metal Oxide Semiconductor (CMOS) transistor.
The protection circuit of any of the preceding two paragraphs may also include any combination of the following features described in this paragraph, as well as other features described herein. Any of the first transistor of the protection circuit, the second transistor of the protection circuit, the first transistor of the amplifier, or the second transistor of the amplifier may include a Bipolar Junction Transistor (BJT). The first power supply terminal, the control terminal, and the second power supply terminal of any transistor described herein may correspond to an emitter terminal, a base terminal, and a collector terminal, respectively, of a BJT. The first power supply terminal, the control terminal, and the second power supply terminal of any of the transistors described herein may correspond to a collector terminal, a base terminal, and an emitter terminal, respectively, or a BJT. Any of the first sensing element, the second sensing element, or the third sensing element can include one or more of a capacitor, a resistor, an inductor, a diode, a MOSFET, a BJT, a transmission line, or a coupler.
For the purposes of summarizing the disclosure, certain aspects, advantages, and novel features of the invention have been described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, the innovations may be implemented or performed in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.
Drawings
The drawings and the related description herein are provided to illustrate specific embodiments and are not intended to be limiting.
Fig. 1 is a diagram illustrating an embodiment of a system including an example protection circuit electrically coupled to an example amplifier.
Fig. 2 is a diagram illustrating an embodiment of a system including an example protection circuit and an example amplifier having a plurality of transistors.
Fig. 3 is a diagram illustrating an embodiment of a system including an example amplifier and an example protection circuit including at least one transistor.
Fig. 4 is a diagram illustrating an embodiment of a system including an example amplifier and an example protection circuit.
Fig. 5 is a diagram illustrating an embodiment of a system including an example amplifier and an example protection circuit.
Detailed Description
Overview
Complementary Metal Oxide Semiconductor (CMOS) Power Amplifiers (PAs) can achieve significant cost and size reductions. However, there are many difficulties in utilizing PAs in Radio Frequency (RF) devices. For example, although CMOS PAs are relatively inexpensive compared to GaN, GaAs, SiGe, and/or silicon bipolar PAs, many CMOS PAs have significant reliability issues. For example, a commercial PA may require a high Voltage Standing Wave Ratio (VSWR), and the strong mismatch condition associated with the high VSWR may result in high voltage spikes at the CMOS transistors. Because CMOS transistors are susceptible to breakdown (e.g., gate oxide or PN junction) if they are exposed to voltages that exceed a threshold voltage corresponding to the breakdown voltage of the transistor, CMOS PAs are more susceptible to breakdown in commercial and other implementations. Nevertheless, the trend toward the use of CMOS PAs in RF and other devices is becoming more apparent as the demand for lower cost increases.
Some techniques for managing problems associated with voltages exceeding the normal operating voltage or threshold operating voltages corresponding to breakdown voltages include coupling a series of diodes to the power supply terminals of the amplifier. For example, in some cases, the swing voltage is greater than or equal to the turn-on voltage of the diode (e.g., a positive amount of voltage must be applied across the diode to cause the diode to conduct current or "turn on" in the forward direction). These swing voltages can therefore open up diodes that can clip the signal and protect the amplifier. However, these techniques are generally not suitable for low voltage processes, e.g., the breakdown voltage of the transistor is less than the turn-on voltage of the diode. Thus, the coupling of the diode to the power supply terminal of the amplifier may not be suitable for CMOS PA protection, at least due to the small or nano-scale processes of CMOS PAs.
To address these and other problems, systems, methods, and apparatus are disclosed for improving reliability and/or reducing or preventing breakdown of an amplifier, particularly breakdown of a transistor of the amplifier. The protection circuit may be electrically coupled to the amplifier and may be configured to reduce a voltage or voltage swing at the amplifier. The amplifier may include a transistor, and the protection circuit may include a transistor electrically coupled to the transistor of the amplifier. For example, a power supply terminal of a transistor of the protection circuit may be electrically coupled to a power supply terminal of a transistor of the amplifier and/or a control terminal of a transistor of the protection circuit may be electrically coupled to a control terminal of a transistor of the amplifier. When the amplifier experiences a voltage (e.g., at a drain or control terminal of a transistor) that satisfies a threshold voltage corresponding to a breakdown voltage of the transistor of the amplifier, at least some energy may be transferred to the protection circuit to reduce the voltage or voltage swing experienced by the amplifier. By reducing the voltage at the transistors of the amplifier, the transistors of the amplifier can continue to operate in a safe operating region. Thus, the protection circuit may advantageously protect the amplifier from breakdown due to voltages exceeding a breakdown voltage threshold, VSWR load variations, and the like. Further, unlike the techniques described above for managing overvoltages, the protection circuit disclosed herein is used to protect an amplifier during low voltages as well as during high or intermediate voltages.
In addition to reduced reliability, smaller feature sizes may make CMOS circuits more susceptible to process, supply voltage, and temperature (PVT) variations. Accordingly, some embodiments of the present disclosure advantageously provide a protection circuit that can limit and/or compensate for PVT variability of an amplifier. For example, the protection circuit may track the circuitry of the amplifier to compensate for PVT variations. That is, the arrangement of at least a portion of the protection circuit may correspond to or match the arrangement of at least a portion of the circuitry of the amplifier. Because the elements of the protection circuit can track the elements of the amplifier, if there is PVT variation, each element of the protection circuit can be affected by PVT variation in the same manner as its corresponding amplifier element. Thus, the protection circuit can provide the same protection and performance to the amplifier even in the presence of PVT variations.
Although generally described herein as being applicable to CMOS PAs, similar protection circuits or techniques may be used for other Metal Oxide Semiconductor Field Effect Transistor (MOSFET) amplifiers, including but not limited to n-type mos (nmos) and p-type mos (pmos) amplifiers. Additionally or alternatively, similar protection circuits or techniques may be used for Bipolar Junction Transistor (BJT) amplifiers.
Over-voltage
Load mismatch at the antenna can cause reflections of the transmitted signal, resulting in standing waves. The amplitude and phase of the reflected signal may be quantified by a reflection coefficient p. If the amplitude of the transmitted signal is VfThe maximum amplitude of the standing wave is Vmax=Vf(1+ | ρ |). Thus, when strongly mismatched applications, standing waves can be up to twice the amplitude of the emitted wave. A measure of load mismatch is the Voltage Standing Wave Ratio (VSWR), which is the ratio between the maximum and minimum voltages of the standing wave. This ratio is shown in
The high voltage standing wave can accelerate long term degradation of the CMOS PA and even lead to breakdown of the CMOS transistors. Thus, as described herein, a barrier to utilizing CMOS PAs and other PAs is the ability of transistors to survive high load Voltage Standing Wave Ratio (VSWR) conditions. Accordingly, systems, methods, and apparatus are disclosed for improving reliability and/or reducing or preventing transistor breakdown of an amplifier by utilizing an improved protection circuit that limits the voltage or voltage swing at the transistors of the amplifier, thereby improving the reliability of the amplifier.
Protective circuit
Fig. 1 is a diagram illustrating an embodiment of a system 100, the system 100 including an
The amplifier 102 may be configured to increase the power of the signal. For example, the amplifier 102 may be a Radio Frequency (RF) Power Amplifier (PA) that may convert a low power RF signal to a higher power RF signal. The amplifier 102 may be configured to drive an antenna (not shown) of a transmitter and/or transceiver (not shown). Additionally or alternatively, the amplifier 102 may be configured to increase the power of a signal received at an antenna (not shown) of a receiver and/or transceiver (not shown).
The amplifier 102 may include at least one
As described above, in some embodiments, the
Additionally or alternatively, in some embodiments, the
Amplifier 102 may include
The
In some embodiments, the
Transistor stack
Fig. 2 is a diagram illustrating an embodiment of a
Similar to the
In the illustrated embodiment, the
One or both of
In some cases, such as high voltage processes, some protection circuits may include one or more diodes that may be electrically coupled to the first power supply terminal of the first transistor. By adding a diode at the output, any extra swing above the required voltage can turn on the diode, which can cut off the signal. However, this technique may not be useful for nanoscale CMOS processes with low breakdown voltages. For example, given a 28nm CMOS process, the breakdown voltage BVDSAbout 0.65 volts, an AC breakdown of about 1.2 volts, negative at 50 ohmsUnder load impedance, 1 volt of large signal swing on a single transistor breaks down about 200mV from the transistor. Thus, a diode turn-on voltage of approximately 500mV to 800mV will not protect the transistor from breakdown. Conversely, the
Fig. 3 is a diagram illustrating an embodiment of a
Similar to the
As described in more detail below, the voltage at the
A benefit of using the topology of fig. 3 is that when the voltage at
For example, the amplifier 102 may experience a voltage at the first
Fig. 4 is a diagram illustrating an embodiment of a
In a CMOS transistor, there are at least three device-specific capacitances between the terminals: capacitances for gate-source, gate-drain and drain-source. In the example of fig. 4, the
As shown, the
Additionally,
The
As described herein, the
Vgz=scale_factor_1*Vgn(equation 3)
Similarly, the
Vdz=scale_factor_2*Vdn(equation 4)
Source voltage VszIs the voltage at the
Drain current IdzMay be described as a current flow between the
Many short channel devices operate in a velocity saturation region. When the
Idz=w*vsat*(vgz↑-vth)*(1+λ*Vdz↓) (equation 6)
As demonstrated by the above relationship, the protection circuit 102 may advantageously protect the
For example, a change in VSWR or ZL causes a drain voltage V at the drain terminal 112dnA change in (c). For example, as VSWR increases, the drain voltage VdnMay also be increased. Drain voltage VdnCauses the drain voltage V at the
PVT compensation
Fig. 5 is a diagram illustrating an embodiment of a
CMOS circuits are susceptible to process, supply voltage, and temperature (PVT) variations compared to other circuits. Among other things, PVT variability can affect the breakdown voltage of a particular transistor. For example, even transistors of the same make and model may have different breakdown voltages based at least in part on PVT variations. Accordingly, in some cases, the
By aligning the tracking amplifier with the same elements (e.g., matching
As shown, the
The concepts described with respect to fig. 5 are compatible with and may be used in conjunction with any combination of the embodiments and/or features described herein, such as those associated with any of fig. 1-4.
Term(s) for
Unless the context dictates otherwise, throughout the specification and claims, the words "comprise," "comprising," "contain," "have," and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is, in the sense of "including, but not limited to". As generally used herein, the term "coupled" refers to two or more elements that may be directly coupled to each other or coupled through one or more intermediate elements. Likewise, the word "connected," as generally used herein, refers to two or more elements that may be connected directly or through one or more intermediate elements. Additionally, as used in this application, the words "herein," "above," "below," and words of similar import shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above detailed description which use the singular or plural number may also include the plural or singular number respectively. The word "or" in reference to a list of two or more items is generally intended to include all of the following interpretations of the word: any item in the list, all items in the list, and any combination of items in the list.
Furthermore, conditional language used herein, such as "may," "for example," "such as," and the like, are generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or states, unless expressly stated otherwise or otherwise understood in the context of such use. Thus, such conditional language is not generally intended to imply that features, elements, and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for determining whether such features, elements, and/or states are included or are to be performed in any particular embodiment.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the present disclosure. Indeed, the novel methods, apparatus, systems, devices, and integrated circuits described herein may be embodied in various other forms; furthermore, various omissions, substitutions and changes in the form of the methods, devices, and systems described herein may be made without departing from the spirit of the disclosure.
The claims presented herein are in a single dependency format suitable for submission by the U.S. patent and trademark office. However, it should be assumed that each of the claims may depend multiple times on any of the preceding claims, unless technically unfeasible.
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