DC-DC transformer with inductor for the facilitation of adiabatic inter-capacitor charge transport

Abstract

The power converter comprises a charge pump, a first regulator that regulates the power provided by the power converter, and a power converter having a magnetic filter connected to a terminal of the charge pump. The specific terminal to which the magnetic filter is connected is selected to facilitate charge transport of an adiabatic capacitor within the charge pump.

Description

Technology Field

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 62 / 132,934 filed on March 13, 2015. The contents of said U.S. Provisional Application are incorporated herein in their entirety.

[0002] This specification relates to power conversion, particularly direct current power conversion. Background Technology

[0003] The disclosed power converter is obtained by placing a regulator in series with a charge pump. An example of the regulator operates by switching an inductor from one state to a second state according to some switch duty cycle. The inductor of such a regulator performs two functions. One is to control the output voltage of the converter. The other is to facilitate adiabatic charge transport between capacitors within the charge pump.

[0004] A known power converter operating according to the above principle is described in U.S. Patent No. 8,860,396, U.S. Patent No. 8,743,553, U.S. Patent No. 8,503,203, U.S. Patent No. 8,693,224, U.S. Patent No. 8,339,184, U.S. Patent No. 8,619,445, U.S. Patent No. 8,723,491 and U.S. Patent No. 8,817,501, the contents of which are incorporated herein by reference in their entirety. The problem to be solved

[0005] The present invention is based on the recognition that the regulator can perform the dual function of regulation and facilitating adiabatic charge transport by means of different components.

[0006] The present invention includes reducing the functionality of a component that has always been used to perform two functions, and relocating it so that one of the functions can no longer be performed. A new circuit component is added to perform the function that was performed by the existing component. Accordingly, the present invention achieves a more complex circuit having additional components that were not required in the prior art.

[0007] The present invention also reduces the die area required for the circuit by increasing the number of components to be placed on the die.

[0008] In addition to reducing the chip area, the present invention described herein provides a power conversion device that enables more voltage conversion to be performed most efficiently within the charge pump by filling specific holes in the performance of the entire power converter. means of solving the problem

[0009] In general, one or more arrangements of power converters are composed of a combination of interconnections of sections including at least a "voltage transformer," a "magnetic filter," and a "current regulator," wherein the aforementioned notations no longer have connotative meanings.

[0010] The power converter has terminals including a first pair of terminals and a second pair of terminals, also referred to as the terminals of the "controller" pair. In at least some embodiments, the operating power converter controls the voltage measured between the controlled pair of terminals. Typically, the power converter receives power at the first pair of terminals from a power source (e.g., an unregulated voltage source) referred to as the "powered" pair of terminals, and supplies power at the second pair of terminals to a controlled voltage (e.g., a substantially resistive load). However, it should be understood that other arrangements may be used.

[0011] The voltage transformer, which should not be confused with a conventional magnetic core AC current "transformer," has at least three terminals and includes a switched arrangement of capacitors. Generally, sequential operation of the switches within the voltage transformer causes a voltage conversion between the first pair of terminals of the voltage transformer and the second pair of terminals of the voltage transformer, generally in a rational multiple. Generally, one pair of terminals is associated with a higher voltage than the other pair. The terminals of the pairs are hereinafter referred to as the terminals of the "high voltage" pair and the terminals of the "low voltage" pair, respectively.

[0012] The sequential operation of the switches causes charge to be transported between the capacitors of the voltage transformer. The charge transport rate is limited by the current passing through at least one of the terminals of the voltage transformer. The terminal is called the "charge transport rate limiting" terminal.

[0013] If the charge transport rate between capacitors in at least one capacitor of the voltage transformer is limited for at least part of the time, for example, by the current at the charge transport rate limiting terminals, the voltage transformer is considered "adiabatic." If at least part of the charge transports, but not all of them, are controlled, the voltage transformer is called "partially adiabatic." Otherwise, the voltage transformer is designated as "completely adiabatic."

[0014] The above magnetic filter includes two terminals coupled to the circuit path without any switching operation. The magnetic filter counteracts variations in the current flowing through at least one of the terminals, hereinafter referred to as the "filtered terminal(s)" of the magnetic filter, and generally maintains a substantially constant current through the filtered terminal(s) during steady-state operation of the power converter. In some examples, the circuit path connecting the terminals includes a passive inductor. In any case, since the path between the two terminals does not require a switch, there is no switch on the path that is sized or selected to accommodate the maximum voltage or current that may be in the path during operation.

[0015] The above current regulator has at least two terminals and includes a switched arrangement of at least one inductor. Generally, the controlled sequential operation of one or more switches of the current regulator controls the current flow through at least one of the terminals of the current regulator (hereinafter referred to as the "controlled terminal"). Generally, the current regulator may regulate the current flow, but the regulation of the current flow may be based on the output voltage (e.g., time-averaged voltage) that can be measured between a pair of terminals of the current regulator, or between other terminals at the interface or inside the power converter.

[0016] A common feature of many embodiments is that the arrangement of the voltage transformer, the magnetic filter, and the current regulator of the power converter is such that the filtered terminal of the magnetic filter is directly coupled to the first terminal of the voltage transformer (i.e., without an intervening switch), and the first terminal is a charge transport control terminal. Preferably, the magnetic filter is coupled to the terminals of a low-voltage pair such that the magnitude of the current flow, as is generally recognized, is higher at the low-voltage terminal than at the high-voltage terminal of the voltage transformer.

[0017] Another common feature is that the controlled terminal of the current regulator is directly coupled to the second terminal of the voltage transformer (different from the first terminal) (i.e., without an intervening switch). The second terminal may be the charge transport rate control terminal of the voltage transformer, but is not necessarily so.

[0018] In some examples, the current regulator is coupled to a plurality of terminals of the voltage transformer or to a plurality of separate voltage transformer portions of the power converter. In other examples, a plurality of current regulators or current regulators having a plurality of separate controlled terminals are coupled to a plurality of terminals of the voltage transformer or to a plurality of separate voltage transformers.

[0019] In the operation of the power converter, the current regulator is controlled to achieve a controlled voltage at the controlled terminals of the power converter.

[0020] Various configurations of the above voltage transformer, magnetic filter, and current regulator may be grouped into classes called "series," "sigma," and "pseudo-series" (which may overlap), and these names do not include specific attributes.

[0021] The configurations of the above series class include configurations in which the current regulator, the voltage transformer, and the magnetic filter are connected in series between the first pair and the second pair of terminals of the power converter. In at least some of the configurations, the magnetic filter is connected to the controlled / load terminals of the power converter and the current regulator is coupled to the powered terminal of the power converter. In at least one of the other configurations, the magnetic filter is coupled to the powered terminal of the power converter and the current regulator is coupled to the controlled terminal of the power converter.

[0022] The configurations of the above sigma class and the above pseudo-serial class include configurations in which one controlled terminal of the current regulator is connected to a controlled terminal of the power converter. The voltage transformer is also coupled to the same (or potentially different) controlled terminal of the power converter through the magnetic filter, so that the magnetic filter provides a path from the charge transport rate control terminal of the voltage transformer to the controlled terminal. In at least some configurations of the sigma class, the other terminal of the current regulator is coupled to the voltage transformer, so that when operating, the control of the current regulator affects the voltage of the first pair or the second pair of terminals of the voltage transformer. For example, the terminals of the first pair of terminals of the voltage transformer are connected to the controlled terminal of the power converter, which is also connected to the controlled terminal of the current regulator through the magnetic filter, and the other terminal of the current regulator is connected to the terminals of the second pair of terminals of the voltage transformer.

[0023] The above sigma class configurations include a configuration in which a path exists from the terminals of the first pair of terminals of the power converter to the terminals of the second pair of terminals of the power converter, passing through the current regulator without passing through the voltage transformer.

[0024] The configurations of the above-mentioned pseudo-series class include not only a configuration in which the voltage transformer is coupled to the controlled terminal of the power converter through a first path that passes through the magnetic filter without passing through the current converter, but also a configuration in which it is coupled through a second path that passes through the current regulator without passing through the magnetic filter.

[0025] In one aspect, the present invention features a power conversion device. The device comprises a power converter having a charge pump, a first regulator that regulates the power provided by the power converter, and a magnetic filter connected to the terminal of the charge pump. The specific terminal to which the above magnetic filter is connected is selected to facilitate charge transport between adiabatic capacitors within the charge pump.

[0026] Embodiments include the charge pump having a first terminal and a second terminal. During operation, the first terminal is maintained at a first voltage and the second terminal is maintained at a second voltage lower than the first terminal. In the embodiments, the magnetic filter is connected to the second terminal, which is the terminal having the lower voltage.

[0027] In other embodiments, the first regulator is positioned to block a first portion of the power provided by the power converter. Meanwhile, the charge pump is positioned to block a second portion of the power provided by the power converter. The magnetic filter is also positioned to block the second portion. The second portion is larger in size than the first portion.

[0028] In other embodiments, the first regulator is positioned to block a first portion of the power provided by the power converter. Meanwhile, the charge pump is positioned to block a second portion of the power provided by the power converter. The magnetic filter is also positioned to block the second portion. The first and second portions are combined at the output of the power converter.

[0029] In another embodiment, the magnetic filter and the first regulator are connected to the output of the power converter. In the embodiment, the first regulator is connected to the first terminal. Among the embodiments, there are embodiments in which the first regulator also includes a ground terminal connected to the first terminal.

[0030] In another embodiment, the charge pump includes first and second charge transport paths. In the embodiments, a first regulator is connected to the first charge transport path, and a magnetic filter is connected to the second charge transport path. Among the embodiments are embodiments in which the second charge transport path has a larger current than the first charge transport path, and embodiments in which the first charge transport path has a larger current than the second charge transport path. Also among the embodiments are embodiments in which there is a second regulator, and the magnetic filter is a component of the second regulator. In some of the embodiments, the first regulator operates in a first duty cycle, and the second regulator operates in a second duty cycle controlled independently of the first duty cycle.

[0031] Some embodiments include a controller for controlling the operation of the regulator based on the output of the power converter. Other embodiments include a clock configured to provide a clock signal to the regulator or the charge pump.

[0032] In addition, among the above embodiments, there are embodiments having a control system configured to control the operation of the power converter based on the measured output of the power converter. Among the above embodiments, there are embodiments having a controller that controls the regulator, a controller that controls the charge pump, having both of the above, having a clock signal input capable of receiving a clock signal, having digital inputs for the controller, having analog inputs for the controller, and combinations of the above-described embodiments.

[0033] Various charge pumps and regulators may be used. For example, among the embodiments are embodiments having a multiphase charge pump, a single-phase charge pump, a multistage charge pump, a two-phase charge pump, a switch-mode power converter, a buck converter, a bidirectional regulator, and a multiphase regulator.

[0034] In some embodiments, the charge pump includes capacitors interconnected by a set of switches. During operation, the first set of switches is in a state opposite to that of the second set of switches.

[0035] In some embodiments, the charge pump is a reconfigurable charge pump. Among the embodiments, there are embodiments in which the regulator is configured to transition from providing a first voltage to providing a second voltage during the reconfiguration of the charge pump.

[0036] In another aspect, the present invention features a power conversion device. The device comprises a charge pump, a first regulator that regulates the power provided by the power converter, and a power converter having a magnetic filter connected to a terminal of the charge pump. A specific terminal to which the magnetic filter is connected is selected to cause a restriction on charge transport between capacitors within the charge pump.

[0037] In another aspect, the present invention features a non-transient computer-readable medium storing a data structure to be operated by a program executable on a computer system, wherein, when operated by said program, said data structure causes at least a part of a process for manufacturing an integrated circuit comprising a circuit described by said data structure, said circuit comprising a switching network configured to be used with a power converter including a charge pump, a first regulator configured to regulate power provided by said power converter, and a magnetic filter connected to a terminal of said charge pump and selected to facilitate charge transport between adiabatic craters within said charge pump.

[0038] Other features and advantages of the present invention will become apparent from the following description and claims. Effects of the invention

[0039] The advantage of at least some configurations of the above sigma and the above quasi-parallel classes is that some of the power flow passing through the power converter passes through the magnetic filter but not through the current regulator. Since the magnetic filter does not introduce a switch in the power flow path through the magnetic filter, power losses (e.g., resistive and capacitive losses in the switch) are reduced and the overall efficiency of the power converter is improved.

[0040] The advantage of at least some configurations of any of the above classes is that the number or range of combinations of terminal voltages supported by the converted power can be increased compared to other configurations that are affected by constraints on voltage differences between the terminals of the pair of current regulators that are smaller than the threshold voltage.

[0041] Another advantage of at least some configurations is that the voltage or current handling requirements of the switches of the converted voltage and / or current regulators may be reduced compared to other configurations. These reduced requirements may result in physically smaller semiconductor devices, which can reduce the size of the integrated circuit implementation of some or all of the power converter. Brief explanation of the drawing

[0042] FIG. 1 illustrates an embodiment of a power converter. FIG. 2 illustrates a switched-capacitor charge pump for use with a power converter such as that shown in FIG. 1. FIG. 3a illustrates terminals connected to the various capacitor networks that are formed and not formed as the charge pump of FIG. 2 transitions to its various states. FIG. 3b illustrates a first capacitor network corresponding to the first configuration of the switches for the charge pump of FIG. 2. FIG. 3c illustrates a second capacitor network corresponding to the second configuration of the switches for the charge pump of FIG. 2. FIG. 4 illustrates a block diagram of the 4-terminal charge pump of FIG. 2. Figure 5 shows a block diagram of the three-terminal charge pump of Figure 3a. FIG. 6a illustrates the components of a conventional regulator that can be used in a power converter such as that shown in FIG. 1. FIGS. 6b through 6d illustrate alternative regulators for use with a power converter such as that shown in FIG. 1. FIGS. 6b through 6d illustrate alternative regulators for use with a power converter such as that shown in FIG. 1. FIGS. 7a and 7b illustrate magnetic filters that can be used in the embodiment of FIG. 1. FIG. 8 illustrates an embodiment in which a diode is used to conduct current in a magnetic filter that has nowhere to go during the dead time of the charge pump. FIG. 9 illustrates the power converter of FIG. 1 having parallel charge pumps and parallel magnetic filters. FIG. 10 illustrates the power converter of FIG. 9 having the magnetic filter that shares a common inductor. FIG. 11 illustrates the power converter of FIG. 1 having the regulator having switches sharing a common inductor. FIG. 12 illustrates an embodiment similar to that shown in FIG. 1, but has a 4-terminal charge pump. FIG. 13 illustrates an embodiment having a branched power path passing through the power converter. FIG. 14a illustrates a circuit implementing the branched power path of FIG. 13, wherein the input voltage is divided so that the voltage provided to the regulator becomes twice the voltage provided to the charge pump. FIG. 14b illustrates a circuit implementing the branched power path of FIG. 13, in which the input voltage is divided so that the voltage provided to the regulator becomes half the voltage provided to the charge pump. FIG. 15a illustrates another embodiment having the branched power path through a power converter. FIG. 15b illustrates a circuit implementing the branched power path of FIG. 15a. FIG. 16a illustrates an isolated pump suitable for use with the structure shown in FIG. 15a. FIG. 16b illustrates a single-phase implementation of the isolated charge pump shown in FIG. 16a. FIG. 16c illustrates a two-phase implementation of the isolated charge pump shown in FIG. 16a. FIGS. 17a to 17d illustrate variations of the architecture shown in FIG. 15a. FIGS. 18a through 18c illustrate circuit topologies having branched power paths with grounded charge pumps. FIGS. 19a through 19c illustrate circuit topologies similar to the circuit topologies of FIGS. 18a through 18c, except that they have grounded regulators instead of charge pumps. FIG. 20 illustrates a power converter that illustrates features common to the embodiments of FIG. 1, FIG. 12, FIG. 13 and FIG. 15. FIG. 21a illustrates a regulated charge pump. FIGS. 21b through 21C illustrate the switch configurations and network states for the regulated charge pump of FIG. 21a. FIG. 22a shows the regulated charge pump of FIG. 21a with the switch removed. FIG. 22b illustrates the switch configurations for the regulated charge pump of FIG. 22a. FIG. 23a illustrates the regulated charge pump of FIG. 22a having a stabilizing capacitor. FIGS. 23b through 23c illustrate the switch configurations and network states for the regulated charge pump of FIG. 23a. FIG. 24a illustrates a regulated charge pump with both switches of the regulator removed. FIG. 24b illustrates the switch configurations for the regulated charge pump of FIG. 24a. FIGS. 25a through 26b illustrate additional switch configurations and network states for the regulated charge pump of FIG. 24a, having only three states and configurations necessary to operate the charge pump. FIG. 27a is a two-phase implementation example of the regulated charge pump of FIG. 24a, and FIG. 27b illustrates the network states for the regulated charge pump of FIG. 27a. Specific details for implementing the invention

[0043] The charge pump has a high-voltage terminal and a low-voltage terminal. For the reason of energy conservation, the high-voltage terminal is associated with a lower current, while the low-voltage terminal is associated with a higher current. The regulator can, theoretically, be placed at both ends.

[0044] However, in order for the inductor of the regulator to participate in the adiabatic charging of all capacitors of the charge pump, it is important that the regulator be connected to the low-voltage side. The above configuration has two disadvantages. One is physical and the other is operational.

[0045] The aforementioned physical disadvantage arises from the fact that the low-voltage terminal of the charge pump discharges a large amount of current. This means that the switch within the regulator must be able to accommodate a very high current. This is most often achieved by physically enlarging the transistor implementing the switch so that the current density at any point within the transistor becomes smaller. Unfortunately, since the switch consumes a large amount of die area, it is necessary to use a larger die. This increases not only the size of the power converter but also the manufacturing cost overall.

[0046] The above operational disadvantage arises from the fact that charge pumps are generally more efficient than regulators in performing voltage conversion. Although the regulator can convert voltage, it is not particularly efficient to do so. It is excellent at providing fine control over voltage and suppressing current ripple. Therefore, when a power converter is required to convert a first voltage to a second voltage, it is desirable for the charge pump to perform as much of the voltage conversion as possible, and for the regulator to perform as little of the voltage conversion as possible.

[0047] There are two limitations that hinder the achievement of this. The first limitation is that the charge pump is designed around a specific integer ratio (n / m). Therefore, for a given input voltage (Vin), the output voltage (Vout) of the charge pump is Vin * (n / m). The ratio is fixed for a specific configuration of the charge pump. Among the functions of the regulator is to reduce the gap between the total element required to reach the target voltage value and the element (n / m) contributed by the charge pump.

[0048] A second limitation arising from the disclosed designs is that there must be a minimum voltage margin between the input and output of the regulator. If the regulator is placed at the low-voltage terminal of the charge pump, it is possible for the output voltage of the charge pump and the target voltage to be smaller than the minimum voltage margin.

[0049] For example, if the desired power converter output is 1.0 volts and Vin is 4.2 volts, 1.4 volts can be maintained at the low-voltage output using a charge pump designed with m / n = 3. Although this slightly exceeds the target voltage, the regulator is intended to reduce the gap between the 1.4 volts and the desired 1.0 volts. This is desirable because much of the required voltage conversion is performed by the more efficient charge pump.

[0050] However, if the above output is provided to a regulator that requires, for example, a minimum voltage margin of 0.6V, it cannot output 1.0V. This creates a significant difference in the performance of the power converter.

[0051] Of course, the above problem can be easily solved by using a charge pump designed with m / n = 2 instead. If this is done, the output of the charge pump becomes 2.1 volts, which is sufficient to provide the 0.6 voltage margin. However, the task of converting the 2.1 volts to the desired 1.0 volts must be performed by the regulator, which is not particularly efficient in doing so.

[0052] In the first embodiment illustrated in FIG. 1, a power converter (10) converts a first voltage (V1) to a second voltage (V2). The power converter (10) includes a regulator (12) and a three-terminal charge pump (14) in series. The three-terminal charge pump (14) has a first CP terminal (16), a second CP terminal (18), and a third CP terminal (17).

[0053] A regulator controller (13) connected to a regulator control output (132) controls the switching activity of the regulator (12) based at least partially on feedback from a feedback line (144) connected to the second voltage (V2). However, the regulator controller (13) may rely on other inputs such as a feedforward line (141), a first intermediate feedback line (142), and a second intermediate feedback line (143). A regulator control input (131), which may be a digital input or an analog input, allows a set point for the operation of the regulator (12) to be input.

[0054] Meanwhile, a charge pump controller (15) connected to a charge pump control output (152) controls the switching activity of the three-terminal charge pump (14). A charge pump control input (151), which may be a digital input or an analog input, allows a set point for the operation of the three-terminal charge pump (14) to be input.

[0055] The power converter (10) further includes a clock (145) connected to the charge pump controller (15) and the regulator controller (13) to ensure that the switches are opened and closed at the correct time and synchronously.

[0056] For clarity, the regulator controller (13), the charge pump (15), and the clock (145) are omitted from certain drawings. However, it should be understood that they are always implicitly present.

[0057] During the operation of the three-terminal charge pump (14), the regulator (12) maintains the first CP terminal (16) at a high voltage but has a low current passing through it. The second CP terminal (18) is maintained at a relatively low voltage by the operation of the three-terminal charge pump (14). The first and second CP terminals (16, 18) share a common ground reference at the third CP terminal (17).

[0058] In particular, for the input voltage (Vh) at the first CP terminal (16), the voltage at the second CP terminal (18) is Vh * (m / n), where m / n is the specified voltage conversion ratio of the specific charge pump. However, the second CP terminal (18) also passes a larger current. Ideally, without loss, the power entering the three-terminal charge pump (14) should be equal to the power leaving the three-terminal charge pump (14). This means that the product of the high current and low voltage at the second CP terminal (18) should be equal to the product of the high voltage and low current at the first CP terminal (16).

[0059] The above 3-terminal charge pump (14) can be implemented using many different charge pump topologies such as Ladder, Dickson, Series-Parallel, Fibonacci, and Doubler. Some of the above topologies can be configured to become a 4-terminal charge pump (74) having 4 terminals, such that the ground reference associated with the first CP terminal (16) and the ground reference associated with the second CP terminal (18) are different.

[0060] FIG. 2 illustrates a four-terminal charge pump (74), which is a two-phase variant of the aforementioned Dickson charge pump also known as a cascade multiplier. In addition to the first and second CP terminals (16, 18), the four-terminal charge pump (74) also includes fourth and fifth CP terminals (116, 118). Unlike the three-terminal charge pump (14) above, the first and second CP terminals (16, 18) of the four-terminal charge pump (74) do not share a common ground reference. Instead, the first CP terminal (16) has its own ground reference at the fourth CP terminal (116), and the second CP terminal (18) has its own ground reference at the fifth CP terminal (118).

[0061] The above four-terminal charge pump (74) features a switching network that causes transitions between a first state and a second state. A switched-capacitor network (21) inside the four-terminal charge pump (74) alternates between the first and second states depending on which of the switches is open and which is closed. A first switch configuration causes the switched-capacitor network (21) to transition from the first state to the second state. A second switch configuration causes the switched-capacitor network (21) to transition from the second state to the first state. The charge pumping operation causes the switched-capacitor network (21) to switch between these states due to the switches.

[0062] When in operation, different amounts of current flow through different switches. Therefore, it is useful to adjust the size of the switches in a manner suitable for the currents flowing through them. For example, the switches connected to the second and fifth CP- terminals (18, 118) carry more current than the other switches in FIG. 2. By making the switches larger than the other switches, the need to have unnecessarily large switches is eliminated, resulting in a smaller circuit footprint. This also avoids unnecessary additional capacitive loss proportional to the size of the switches.

[0063] FIG. 3a illustrates the terminals connected to the switched-capacitor network (21) of the four-terminal charge pump (74). The four-terminal charge pump (74) transitions constantly between each state, which is a different capacitor network. In the following description, the switched-capacitor network (21) illustrated in FIG. 2 will be illustrated in only one state or the other. Consequently, the spread of switches illustrated in FIG. 2 does not need to be shown further.

[0064] Of course, there is no state that can actually define the 4-terminal charge pump (74) beyond identifying a single frame that defines the movie. Recognizing this, the switched-capacitor network (21) is shown as a blank screen in FIG. 3a. Either the first state (21A) or the second state (21B) is projected onto the blank screen. The actual switched-capacitor network in FIG. 3A depends exactly when it is viewed. Sometimes the switched-capacitor (21) is in its first state (21A) as shown in FIG. 3b, and sometimes it is in its second state (21B) as shown in FIG. 3c.

[0065] The first and second states (21A, 21B) are essentially symmetrical. Although the topology may appear identical, a close examination of Figures 3B and 3C reveals that the capacitors have switched locations. The above switching points are performed by the switches shown in FIG. 2.

[0066] The 4-terminal charge pump (74) shown in Fig. 4 has three internal charge transport paths. The first charge transport path between the 5th CP terminal (118) and the 2nd CP terminal (18) carries a first current (iP). The first charge transport path carries the highest current. The second charge transport path between the 1st CP terminal (16) and the 2nd CP terminal (18) carries a second current (iH). The third charge transport path between the 5th CP terminal (118) and the 4th CP terminal (116) carries a third current (iL). Thus, the current present at the 2nd CP terminal (18) is the sum (iP + iH). The current is approximately equal to N * iH, where N depends on the topology of the switched-capacitor network (21). In the embodiment, the grounds are not completely isolated because there is a charge transfer path between them.

[0067] The above 3-terminal charge pump (14) can be generated from the 4-terminal charge pump (74) by short-circuiting the 4th CP terminal (116) with the 2nd CP terminal (18) and short-circuiting the 5th CP terminal (118) with the 3rd CP terminal (17). A block diagram of the resulting charge pump is shown in FIG. 5.

[0068] From FIG. 5, it is evident that there are two internal charge transport paths within the three-terminal charge pump (14). The first charge transport path between the third CP terminal (17) and the second CP terminal (18) carries a first current (iP + 1L). The first charge transport path carries the highest current. The second charge transport path between the first CP terminal (16) and the second CP terminal (18) carries a second current (iH). Thus, the current present at the second CP terminal (18) is the sum (iP + iH + iL). The current is approximately equal to (N + 1) iH, where N depends on the topology of the switched-capacitor network (21).

[0069] In the embodiment illustrated in FIG. 1, the regulator (12) is positioned between the first voltage (V1) to be converted and the first CP terminal (16) of the three-terminal charge pump (14). This hinders the ability to promote charge transport between the capacitors of the three-terminal charge pump (14) and the adiabatic capacitor of the regulator. To improve this ability, it is preferable to connect the regulator (12) to the second CP terminal (18).

[0070] It is evident from FIGS. 3b to 3c that it is preferable to position the regulator (12) at the second CP terminal (18). An examination of the network topology shows that the inductor coupled to the second CP terminal (18) can be coupled to all capacitors within the switched-capacitor network (21). Therefore, this can simultaneously affect all three charge transport paths. In contrast, the inductor coupled to the first CP terminal (16) affects only the second charge transport path between the first CP terminal (16) and the second CP terminal (18). Furthermore, the second charge transport path does not carry as much current as the first charge transport path between the fifth CP terminal (118) and the second CP terminal (18). Therefore, to reduce losses, it is more important to affect the first charge transport path.

[0071] In the configuration shown in FIG. 1, the regulator (12) is partially side-wired. The regulator can still regulate the current at the second CP terminal (18). However, it loses the ability to facilitate charge transport between adiabatic capacitors.

[0072] However, connecting the regulator (12) to the first CP terminal (16) instead of the second CP terminal (18) has no advantages. In particular, at the first CP terminal (16), only a small current (iH) flows through the regulator (12). This means that the various components within the regulator (12) no longer need to be made sized to accommodate the larger current (iH + iP) present at the second CP terminal (18).

[0073] In particular, in a general embodiment of the regulator (12) such as that shown in FIG. 6a, the switch (20) periodically connects the inductor (22) to a first state and a second state according to the duty cycle. The switch (20) ultimately withstands the current passing through the regulator (12) completely. Since the practical switches (20) are implemented with semiconductor materials, there is a risk that the switches (20) will overheat. Since the heat generated in the bulk material is the product of the resistivity and the current density, one way to accommodate a large amount of current while reducing excessive heating of the semiconductor switch (20) is to simply diffuse the current over a wider area of ​​the semiconductor material to lower the current density. However, the above results in a switch (20) that consumes a large area on the semiconductor die.

[0074] Many different regulator configurations have a switch (20) that periodically connects the inductor to a first state and a second state for regulation. Other examples are illustrated in FIGS. 6b to 6d, showing the features of a boost converter in FIG. 6b, a boost-buck converter in FIG. 6c, and a flyback converter in FIG. 6d. Although the regulators differ somewhat in their topology, they all feature a switch (20) that modulates an inductor (22) (or transformer). Other suitable regulators include flyback converters, quasi-resonant flyback converters, active-clamp flyback converters, interleaved flyback converters, Cuk converters, SEPIC converters, resonant converters, multi-level converters, forward converters, two-switch forward converters, active-clamp forward converters, interleaved forward converters, multi-resonant forward converters, half-bridge converters, asymmetric half-bridge converters, multi-resonant half-bridge converters, LLC resonant half-bridge converters, and full-bridge converters.

[0075] As shown in FIG. 1, when the regulator (12) is connected to the first CP terminal (16), the switch (20) needs to accommodate only a smaller current than it would have accommodated if it were connected to the second CP terminal (18). Of course, the switch (20) may need to be designed to accommodate the high voltage at the first CP terminal (16). However, the trade-off is usually advantageous in most designs.

[0076] Another advantage of connecting the regulator (12) to the first CP terminal (16) is that it does not require the same size of inductance as when the inductor (22) is connected to the second CP terminal (18). This reduces the DC resistance of the inductor (22) and thus reduces energy losses associated with the current passing through the inductor (22).

[0077] Charge transport between adiabatic capacitors is desirable regardless of where the regulator (12) is placed. If the inductor (22) within the regulator (12) is no longer available for this purpose, it is necessary to add another component to the power converter (10). This increases the number of components and consequently increases circuit complexity.

[0078] To facilitate intra-capacitor charge transport within the three-terminal charge pump (14), the embodiment described above in FIG. 1 features a magnetic filter (24) connected to the second CP terminal (18). The magnetic filter (24) includes an inductor that tends to facilitate charge transport between the intra-capacitors within the three-terminal charge pump (14).

[0079] The switches illustrated in FIG. 2 will transition between states at a certain switching frequency. To reduce losses, it is desirable for the charge pump (14) to operate adiabatically at the switching frequency. One way to ensure this is to select the resistances of the switches large so that the RC time constant of the charge transport between the capacitors is similar when the switching frequency is not greater than the switching frequency. Unfortunately, this increases the resistance losses. The magnetic filter (24) operates adiabatically by reducing the resistance of the switches without causing significant redistribution losses. Thus, the switches can be made optimally sized for the highest efficiency without worrying about redistribution losses. The optimal size of each switch is selected by balancing the resistive and capacitive losses of each switch at a given switching frequency and a given current.

[0080] Another advantage of connecting the regulator (12) to the first CP terminal (16) occurs in certain dynamically reconfigurable charge pumps.

[0081] In some cases, the first voltage (V1) shown in FIG. 1 may fluctuate significantly. For example, there may be cases where the voltage across the regulator (12) drops to a level where it is not sufficient for proper operation. This requires reducing the voltage conversion ratio of the three-terminal charge pump (14) to provide sufficient margin voltage for the regulator (12) to operate. The dynamic reconfiguration may be performed using charge pumps such as those described in U.S. Patent No. 8,817,501.

[0082] If the charge pump is of a new configuration, the voltages across the capacitors of the charge pump may need to be changed to suit the new configuration. Such changes often need to occur rapidly. Rapid changes in capacitor voltage require a very large current.

[0083] In some charge pumps, the capacitor voltages are set to any value provided at the second CP terminal (18). An example of the configuration is the configuration shown in FIGS. 3a through 3c, and it can be seen that the voltage across the capacitors is a function of the voltage between the second CP terminal (18) and the third CP terminal (17). In the case of the charge pump configurations, dynamic reconfiguration can draw a significant current through the first CP terminal (16) when the charge pump starts operating in the new configuration.

[0084] As illustrated in FIG. 1, placing the regulator (12) in front of the three-terminal charge pump (14) and carefully synchronizing the operation of the regulator (12) with the dynamic reconfiguration of the three-terminal charge pump (14) can avoid the above disturbance. In particular, while the three-terminal charge pump (14) is in the old configuration, the regulator (12) supplies a first intermediate voltage to the three-terminal charge pump (14) through the first CP terminal (16). Then, during the short interval while the reconfiguration is actually taking place, the regulator (12) is quickly adjusted to provide a second intermediate voltage more suitable for the new configuration of the charge pump instead of providing the first intermediate voltage. When the dynamic reconfiguration is complete, the three-terminal charge pump (14) resumes operation. However, by the time mentioned above, the regulator (12) is already ready to supply the correct second intermediate voltage at the first CP terminal (16) and is waiting.

[0085] The magnetic filter (24) can be produced in many different ways. FIG. 7a illustrates one embodiment of the magnetic filter (24) featuring a first inductor (26) and, optionally, a capacitor (28).

[0086] FIG. 7b illustrates another magnetic filter (24) featuring a second inductor (27) in addition to the first inductor (26) and the capacitor (28). The embodiment of the magnetic filter (24) is a third-order low-pass filter and is therefore more effective than the magnetic filter (24) of FIG. 7a in attenuating high frequencies.

[0087] A charge pump continuously opens and closes one or more switches. In particular, if there is an inductor in the circuit, it is important that there be a place for the current flowing through the circuit to flow whenever a switch is opened. Otherwise, the switch may be damaged.

[0088] Between the first state and the second state of the charge pump (e.g., the three-terminal charge pump (14)), there is a dead time interval during which all the switches in the switched-capacitor network (21) are open. In principle, since the switches do not switch instantaneously, the dead time interval is not practically necessary. Therefore, it is necessary to provide a margin to avoid the undesirable result of the switches closing simultaneously.

[0089] In a preferred embodiment, the magnetic filter (24) connected to the second CP terminal (18) of the power converter (10) is modified to include a circuit element for safely shunting the current, otherwise there would be no place for it during the dead-time of the three-terminal charge pump (14). In the embodiment shown in FIG. 8, a shunting diode (29) is used to direct the current. Alternatively, if the dead time interval in the switched-capacitor network (21) is not too long, the branch capacitor can be connected to ground to temporarily store excess charge during the interval and release the excess charge when the switches are properly reconnected. In some cases, a switch is placed in series with the branch capacitor so that the branch capacitor can be disconnected from the circuit when not needed. This prevents the branch capacitor from interfering with the circuit operation.

[0090] FIG. 9 illustrates a modified example of the power converter (10) of FIG. 1 in which the output of the regulating circuit (12) is connected in parallel to a plurality of three-terminal charge pumps (14). Each three-terminal charge pump (14) has a corresponding magnetic filter (24) at its second CP terminal (18). The outputs of each magnetic filter (24) are combined at a common node which is the second voltage (V2) of the power converter (10).

[0091] FIG. 10 illustrates a variation of the embodiment of FIG. 9 in which the magnetic filter (24) is configured using a combined inductor (26). The combined inductor (26) is configured by having two windings that share a common core.

[0092] The above idea of ​​a combined inductor as shown in FIG. 10 can also be used in the regulator (12). This is shown in FIG. 11, which shows a combined inductor (22) shared by two switches (20) with the regulator (12) as shown in FIG. 6a open.

[0093] FIG. 12 illustrates another embodiment in which a regulator (12), a four-terminal charge pump (74), and a magnetic filter (24) are connected in series. However, unlike the embodiment of FIG. 1, the four-terminal charge pump (74) is used instead of the three-terminal charge pump (14). The four-terminal charge pump (74) is a four-terminal charge pump rather than the three-terminal charge pump (14) shown in FIG. 1. Because there are more terminals, there are more options for interconnection. For example, in the illustrated specific example, the first and second voltages (V1, V2) are opposite polarities as a result of the orientation of the grounds. This A simple method is provided to change the polarity of the input voltage without additional stages (e.g., a polarity inversion stage).

[0094] In the embodiments discussed so far, all power passing through the power converter (10) flows through both the regulator (12) and the three-terminal charge pump (14). However, in certain embodiments, the power path is branched within the power converter so that the power bypasses the regulator (12).

[0095] FIG. 13 illustrates an embodiment of achieving branched power paths, one of which carries more power than the other. In FIG. 13, the first power path (30) and the second power path (32) cross the power converter (10). The heavier line on the second power path (32) indicates that it carries the higher of the two powers. Conversely, the lighter line on the first power path (30) indicates that it carries the lower of the two powers.

[0096] The second power path (32) carries power passing through the three-terminal charge pump (14). Meanwhile, the first power path (30) bypasses the three-terminal charge pump (14) during the process and passes through the regulator (12). Since the three-terminal charge pump (14) is more efficient in performing voltage conversion, it is preferable for most of the power to use the second power path (32).

[0097] An additional advantage of the branched power path is that the regulator (12) can be used to provide an additional offset to the voltage difference across the first CP terminal (16) and the third CP terminal (17) of the three-terminal charge pump (14). There is an extra degree of freedom available to control the voltage at the output of the power converter (10). This provides greater flexibility, and therefore has a smaller voltage range in which the power converter (10) cannot provide the desired output voltage.

[0098] In the embodiment illustrated in FIG. 13, the voltage at the output (83) of the regulator (12) is the same as the voltage at the output (38) of the magnetic filter (24). This is achieved by connecting the ground terminal (86) of the regulator (12) to the first CP terminal (16) of the three-terminal charge pump (14). The output (83) of the regulator (12) connected to the first CP terminal (16) of FIG. 1 is instead connected to the output (38) of the magnetic filter (24).

[0099] FIG. 14a illustrates an exemplary circuit that converts a 12-volt input voltage at a load (40) to a 1-volt output using the configuration of FIG. 13. A 4-volt input is provided at the first CP terminal (16) of the three-terminal charge pump (14). The above 3-terminal charge pump (14), which is a 4:1 charge pump, outputs 1 volt at its second CP terminal (18).

[0100] Meanwhile, the remaining 8 volts are provided across the input terminal (81) and ground terminal (86) of the regulator (12), which provides -3 volts to the output (83) of the regulator (12). However, the -3 volts are measured against the ground of the regulator (12), which is not equal to the voltage of the three-terminal charge pump (14). Since the ground terminal (86) of the regulator (12) is connected to the first CP terminal (16) of the three-terminal charge pump (14), it must also be 4 volts. Therefore, the voltage measured at the output (83) of the regulator (12) will actually be 1 volt (i.e., 4-3) when measured against the ground of the three-terminal charge pump (14). Consequently, the voltage at the output (83) of the regulator (12) and the output (38) of the magnetic filter (24) must naturally be the same at the load (40).

[0101] FIG. 14b illustrates the circuit of FIG. 14a used to convert a 12-volt input voltage to a 2-volt output at the load (40). Unlike the circuit of FIG. 14a, the voltage provided to the regulator (12) is half the voltage provided to the three-terminal charge pump (14) instead of the other way.

[0102] When operating, an 8-volt input is provided to the first CP terminal (16) of the three-terminal charge pump (14). The above 3-terminal charge pump (14), which is a 4:1 charge pump, outputs 2 volts at its second CP terminal (18) as needed.

[0103] Meanwhile, the remaining 4 volts are provided across the input terminal (81) and ground terminal (86) of the regulator (12), which provide -6 volts to the output (83) of the regulator (12). However, the above -6 volts is measured against the ground of the regulator (12), which is not the same as the voltage of the three-terminal charge pump (14). Since the ground terminal (86) of the regulator (12) is connected to the first CP terminal (16) of the three-terminal charge pump (14), it must also be 8 volts. Therefore, the voltage measured at the output (83) of the regulator (12) actually becomes 2 volts (i.e., 8-6) when measured against the ground of the three-terminal charge pump (14). Consequently, the voltage at the output (83) of the regulator (12) and the output (38) of the magnetic filter (24) at the load (40) must also be the same.

[0104] With isolated charge pumps such as a 4-terminal charge pump (74), it becomes possible to create alternative structures that branch off the power path through which only a portion of the total power passes through the regulator (12). FIG. 15 illustrates such a structure.

[0105] Referring to FIG. 15a, the first power path (30) starts at the fourth CP terminal (116) and leads to the input terminal (81) of the regulator (12), and the second power path (32) starts at the second CP terminal (18) and leads to the magnetic filter (24). Most of the power passes through the second power path (32). This configuration is advantageous because the regulator (12) is not burdened with carrying all the power passing through the power converter (10). As in FIG. 13, the output (83) of the regulator (12) and the output (38) of the magnetic filter (24) meet at a common node, which is the second voltage (V2) of the power converter (10) to which the load (40) is connected.

[0106] FIG. 15b is an example of the implementation of the embodiment shown in FIG. 15a. The shown configuration is similar to the configuration shown in FIG. 14b, except for the configuration shown in FIG. 15b, and is the grounded regulator and the floating charge pump.

[0107] The embodiments of the type illustrated in FIG. 15a require that the regulator (12) and the four-terminal charge pump (74) have separate grounds. This A fully isolated version of the above-mentioned four-terminal charge pump (74) is required, an example of which is illustrated in FIG. 16a. During operation, the fully isolated version of the above-mentioned four-terminal charge pump (74) illustrated in FIG. 16a transitions between a first state and a second state. During the first state, the switches of the first switch set (1) are opened and the switches of the second switch set (2) are closed. During the second state, the switches of the second switch set (2) are opened and the switches of the first switch set (1) are closed.

[0108] While the above 4-terminal charge pump (74) is in its first state, the coupled capacitor (C C ) stores a charge sufficient to maintain the voltage across the first CP terminal (16) and the fourth CP terminal (116). Then, when the charge pump (74) switches to its second state, the coupling capacitor (Cc) provides its maintained voltage to the three-terminal charge pump (14) contained within the four-terminal charge pump (74).

[0109] This operates for any type of charge pump topology, two examples of which are illustrated in FIG. 16b and FIG. 16c.

[0110] In particular, FIG. 16b illustrates the structure of the charge pump (74) of FIG. 16a used with a cascade multiplier type similar to the charge pump of FIG. 3a to 3c, the difference being that the voltage conversion ratio and the number of phases are different.

[0111] FIG. 16c is a two-phase version of the four-terminal charge pump (74) of FIG. 16b. Unlike the embodiment shown in FIG. 16b, the embodiment can draw a continuous input current. As a result, the first and second DC capacitors (C of FIG. 15b) DC1 , C DC2 The above size of ) can be reduced.

[0112] The specific embodiments illustrated in FIG. 16b and 16c include a pair of switches having switches that belong to the same set of switches and are in series. For example, the embodiment of FIG. 16b includes one of the switch pairs between the coupling capacitor (Cc) and the pump capacitor (C1). Since each of the switches in the switch pair belongs to the first set of switches (1), they always open and close together. Therefore, additional switches can be removed by merging the switches of each switch pair. The embodiment of FIG. 16c includes two switch pairs located in similar positions, but they are merged in the figure.

[0113] FIGS. 17a through 17d illustrate variations of four possible configurations for the structure of FIG. 15. These examples differ in whether or not a magnetic filter (24) is used, and if used, which charge pump terminal is connected to the magnetic filter.

[0114] In the first configuration (42) shown in FIG. 17a, the regulator (12) is connected to the second CP terminal (18) of the four-terminal charge pump (74), and the magnetic filter (24) is connected to the fourth CP terminal (116) of the four-terminal charge pump (74). A suitable regulator for the configuration is a boost converter.

[0115] The second configuration (44) shown in FIG. 17b is the opposite of the first configuration (42). The second configuration (44) is particularly advantageous because most of the current flows through the second CP-terminal (18). Accordingly, the regulator (12) is placed at a lower current terminal to obtain all the advantages associated with the above placement as described above.

[0116] The third configuration (46) shown in Fig. 17c does not require a magnetic filter (24) at all and has only a regulator (12) connected to the second and fourth CP terminals (18, 116) of the four-terminal charge pump (74).

[0117] The fourth configuration (48) illustrated in FIG. 17d also does not require the magnetic filter (24) but uses separate regulators (12) at the second and fourth CP terminals (18, 116). The fourth configuration provides significant flexibility because the duty cycles of each regulator (12) can be controlled independently of each other.

[0118] In the third configuration (46) illustrated in FIG. 17c, only multiplication control for the second voltage (V2) exists. In particular, the second voltage (V2) is given by the product of the first voltage (V1) and ((N + 1) / (D + 1)), where N is the number of stages of the four-terminal charge pump (74), D is the duty cycle of the regulator (12), and D = 1 corresponds to a permanently closed switch.

[0119] Meanwhile, the first and second configurations (42, 44) illustrated in FIGS. 17a and 17b provide a combination of addition and multiplication control for the second voltage (V2).

[0120] In particular, in the first configuration (42) shown in FIG. 17a, the second voltage (V2) is given by the product of the first voltage (V1) and (1 + N / (1-D)).

[0121] In the second configuration (44) illustrated in FIG. 17b, the second voltage (V2) is given by the product of the first voltage (V1) and (N + 1 / (1-D)). This provides greater flexibility because the addition and multiplication controls are separated.

[0122] The fourth configuration (48) shown in FIG. 17d provides greater flexibility in terms of control due to the presence of another degree of freedom. In the fourth configuration (48), the second voltage (V2) is given by the product of the first voltage (V1) and ((1 / (1-D2)) + (N / (1-D1))), where D1 and D2 are the duty cycles for the two regulators shown in FIG. 17d.

[0123] The circuits described above represent various topologies that provide parallel power paths. However, many other topologies are illustrated in FIGS. 18a to 18c and FIGS. 19a to 19c.

[0124] FIGS. 18a through 18c illustrate three topologies in which the four-terminal charge pump (74) has a ground separated from the ground of the regulator (12). The terms “down” and “up” indicate the direction of the voltage conversion. Thus, a circuit element identified as “down” will have its output at a voltage lower than its input. In contrast, a circuit element identified as “up” will have its output at a voltage higher than its input.

[0125] FIGS. 19a through 19c illustrate topologies in which the regulator (12) is isolated from the three-terminal charge pump (14). These topologies require a regulator with a built-in transformer, such as a flyback converter. As in the case of FIGS. 18a through 18c, the regulator and the charge pump may operate in tandem or in opposite directions.

[0126] FIG. 20 integrates and summarizes the embodiments illustrated in FIG. 1, FIG. 12, FIG. 13, and FIG. 15a, and draws particular attention to the basic modularity of the concepts described herein. The components of the three general classes described herein, namely The regulator (12) (applicable in both isolated and non-isolated versions), the four-terminal charge pump (74) (applicable in both isolated and non-isolated versions), and the magnetic filter (24) can be mixed and matched in various ways to achieve various technical goals. However, what the embodiments have in common is the ability to separate the task of regulation from the task of promoting adiabatic charge transport within the three-terminal charge pump (14).

[0127] The circuit topologies described herein allow for the elimination of the large switch associated with having a regulator connected to the terminals of a charge pump having low voltage and high current. Instead, an inductor replaces the regulator. The inductor can perform one of the functions of the regulator in the prior art, namely, facilitating charge transport between adiabatic capacitors within the charge pump. However, that function was precisely achieved by fixing the regulator to the low-voltage second CP terminal (18) of the charge pump. The fact that the regulator is fixed to the second CP terminal (18) caused many technical problems, including the introduction of dead zones that could be inconveniently located and the need to allocate a large die space for the large switches required for those locations. Once removed from its position at the second CP terminal (18) of the charge pump, the regulator can now be placed in several other locations. This, in turn, allows the circuit designer to adjust the locations of the inoperable regions according to the requirements of the power converter. Additionally, significant die space can be saved by using a switch of a more suitable size in the regulator.

[0128] In some of the embodiments described so far, the regulator (12) is connected to the first CP terminal (16) of the three-terminal charge pump (14). This means that the current flowing through the switch (20) in the regulator (12) is less. Consequently, the size of the switch (20) is reduced. However, these embodiments have the disadvantage that the switch size is still greater than 0.

[0129] In other embodiments described so far, the power path is branched so that most of the current bypasses the regulator (12) and bypasses the switch (20). This approach may make the switch (20) smaller. However, this approach has the disadvantage of still allowing some current to flow through the switch (20).

[0130] In another embodiment, the switch size is reduced to zero, substantially eliminating the problem but without abandoning the regulating function of the regulator (12). The resulting circuit is called a "regulated charge pump" and minimizes losses due to the switch (20) by having the three-terminal charge pump (14) and the regulator (12) share a common set of switches, so that neither of them will bear all the current passing through the power converter (10).

[0131] As a first example, FIG. 21a illustrates a buck converter (12) and a three-terminal charge pump (14) that are combined to form a first regulated charge pump (41). The first regulated charge pump (41) still has the switch (20) that was originally in the regulator (12). The switch (20) carries a significant current. The operation of the first regulated charge pump (41) involves circulating the circuit through a first set of network states (51) using a first set of switch configurations (61) as shown in FIG. 21b through 21c. Thus, a disadvantage of the first regulated charge pump (41) is that the switch (20) is still present.

[0132] The second regulated charge pump (42) shown in FIG. 22a removes the switch (20). In fact, the functionality of the switch (20) is integrated into the three-terminal charge pump (14). The operation of the second regulated charge pump (42) involves achieving the same first set of network states (51) but using a different second set of switch configurations (62) as shown in FIG. 22b.

[0133] The disadvantage of the second regulated charge pump (42) is that all switches must operate at the same frequency. This can be inconvenient because the capacitors and the inductor tend to have different energy densities. However, in cases where the current is significantly high, the advantage of removing the switch (20) may outweigh the disadvantage.

[0134] Another disadvantage of the above second regulated charge pump (42) is that the entire circuit can potentially become an unstable oscillator. To reduce the possibility of the above occurrence, the third regulated charge pump (43) shown in FIG. 23a introduces a stabilizing capacitor (94) and a stabilizing switch (96). Since only a small amount of current needs to flow into the stabilizing capacitor (94), the loss from the stabilizing switch (96) is minimal. The operation of the third regulated charge pump (43) involves circulating through the second set of network states (53) using the third set of switch configurations (63) as shown in FIG. 23b through FIG. 23c.

[0135] Up until now, in the regulated charge pump, the first switch (20) of the regulator (12) has been removed, but the second switch remains. In the fourth regulated charge pump (44) shown in FIG. 24a, even the switch is removed. The resulting circuit is essentially a three-terminal charge pump (14) having an LC circuit (98) at its output terminal. The operation of the fourth regulated charge pump (44) involves circulating through the first set of network states (51) using the fourth set of switch configurations (64) as shown in FIG. 21b and FIG. 24b, respectively.

[0136] The above-mentioned fourth regulated charge pump (44) can also be operated by circulating through three network states instead of four. This reduces switching losses associated with each switch transition because there are fewer switch transitions per cycle. The two alternatives are represented as corresponding fifth and sixth sets of three switch configurations (68, 69) as shown in FIGS. 25a through 26b, and third and fourth sets of network states (58, 59) each consisting of three states rather than four states.

[0137] The technique used to remove two switches from the regulator (12) used in connection with the fourth regulated charge pump (44) shown in FIG. 24a can be used to implement a two-phase version, which is the fifth regulated charge pump (45) shown in FIG. 27a.

[0138] The operation of the fifth regulated charge pump (45) includes circulating through the fifth set of network states (55) using the fourth set of switch configurations (64), as illustrated in FIG. 27b and FIG. 24b, respectively.

[0139] In some implementation examples, a computer-accessible storage medium includes a database representing one or more components of the converter. For example, the database may include data representing a switching network optimized to facilitate low-loss operation of the charge pump.

[0140] Generally speaking, a computer-accessible storage medium may include any non-temporary storage medium accessible by a computer during use to provide commands and / or data to the computer. For example, a computer-accessible storage medium may include storage media such as magnetic or optical disks and semiconductor memories.

[0141] Generally, the database representing the system may be a database or other data structure that can be read by a program and used directly or indirectly to manufacture the hardware including the system. For example, the database may be a behavioral-level description of a high-level design language (HDL) such as Verilog or VHDL, or a register transfer-level (RTL) description of the hardware functionality. The above description can be read by an analysis tool capable of analyzing the above description to generate a netlist containing a list of gates from an analysis library. The netlist also includes a set of gates representing the functionality of the hardware constituting the system. The netlist can then be placed and routed to generate a data set describing geometric shapes to be applied to masks. The masks can then be used in various semiconductor manufacturing steps to generate semiconductor circuits or circuits corresponding to the system. In other examples, the database itself may be the netlist or the data set (with or without the analysis library).

[0142] Describing the present invention and its preferred embodiments, which are claimed to be novel and guaranteed by written patents are:

Claims

Claim 1 A device comprising a power converter configured to convert a first voltage at a first power converter terminal to a second voltage at a second power converter terminal, wherein the power converter comprises a charge-pump switching network configured to interconnect capacitors within a capacitor network and a magnetic filter, wherein the magnetic filter comprises a first magnetic filter terminal and a second magnetic filter terminal, wherein when the capacitors are connected to a switch from the switching network, the magnetic filter is configured to impose a restriction on charge transport between the capacitors, and the second magnetic filter terminal is maintained at the second voltage, and the power converter is configured to switch the switches at a common frequency, and the charge-pump switching network is configured to transition between states, wherein the states include a first state, a second state, and a third state, wherein in both the first state and the third state, the first magnetic filter terminal is coupled to the capacitor network, and in the second state, the first magnetic filter terminal is grounded, and the second state is controlled to occur between the first state and the third state. Claim 2 In claim 1, the device comprises capacitors and a charge pump switching network including a single-phase charge pump. Claim 3 In claim 1, the device comprises capacitors and a charge pump switching network including a multiphase charge pump. Claim 4 A device according to claim 1, wherein in the first state, the first magnetic filter terminal is coupled to the cathode of the first capacitor and the anode of the second capacitor, and in the third state, the anodes of the first and second capacitors are coupled to each other and the first magnetic filter terminal is coupled to the cathode of one of the first and second capacitors. Claim 5 An apparatus according to claim 1, wherein the states include a fourth state, the fourth state is selected from the first state, the second state, or the third state, and the charge pump switching network is configured to execute a cycle, the cycle starts with a transition from the fourth state and ends with a transition to the fourth state, and the cycle includes three transitions between the states. Claim 6 An apparatus according to claim 1, wherein the states include a fourth state, the fourth state is selected from the first state, the second state, or the third state, and the charge pump switching network is configured to execute a cycle, the cycle starts with a transition from the fourth state and ends with a transition to the fourth state, and the cycle includes four transitions between the states. Claim 7 In paragraph 5, the device wherein, during the above cycle, the second state occurs twice. Claim 8 The device according to claim 1, wherein the charge pump switching network comprises charge pump switches and a stabilizing capacitor configured to connect the stabilizing capacitor to the first magnetic filter terminal and to disconnect the stabilizing capacitor from the first magnetic filter terminal. Claim 9 A device according to claim 8, wherein, during a switching cycle, each charge pump switch in the charge pump switching network is configured to conduct current through it, and the stabilization switch is configured to conduct less current than each charge pump switch. Claim 10 In claim 1, the device wherein the second magnetic filter terminal is coupled to a capacitor. Claim 11 A device according to claim 1, wherein the charge pump switching network includes a first switch, and the first switch is configured to connect the first magnetic filter terminal to the capacitor network and disconnect the first magnetic filter terminal from the capacitor network. Claim 12 A device according to claim 11, wherein the charge pump switching network comprises a second switch, and the second switch is configured to connect the first magnetic filter terminal to ground when the first switch disconnects the first magnetic filter terminal from the capacitor network, and otherwise the second switch is open. Claim 13 A device according to claim 1, wherein the charge pump switching network comprises a first switch, the first switch transitions between a first state and a second state, and in the first state, the first magnetic filter terminal is connected to ground, and in the second state, the first magnetic filter terminal is disconnected from ground. Claim 14 The device according to claim 1, wherein the magnetic filter comprises an LC circuit configured to be connected to the capacitor network. Claim 15 In claim 1, the device wherein the capacitor network and the charge pump switching network comprise a two-phase charge pump. Claim 16 A clock configured to generate at least one timing signal; a controller configured to implement a dead time interval based at least partially on at least one clock signal; A power converter comprising a power path between an input port and an output port, wherein the power converter comprises a plurality of switches, a regulator, a switch capacitor array comprising a single-phase charge pump, and a magnetic filter disposed on the power path, and the power converter is configured to maintain a first voltage and a second voltage corresponding to the input and the output, and during the operation of the power converter, the plurality of switches are operable by a controller to switch between at least a first switch configuration and a second switch configuration to interconnect at least a first and second capacitor of the switched capacitor array, the first switch configuration corresponds to a first state of the switched capacitor array and the second switch configuration corresponds to a second state of the switched capacitor array, wherein in the first switch configuration, the first capacitor is charged at a first rate and in the second switch configuration, the first capacitor is discharged at a second rate, and the first and second rates are constrained by at least one coupled inductor, wherein the at least one coupled inductor comprises a regulator; a magnetic filter; A device comprising at least one of any combination thereof, wherein the at least one combined inductor facilitates charge transport between adiabatic capacitors among some capacitors of the switch capacitor array. Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete Claim 21 delete Claim 22 delete Claim 23 delete Claim 24 delete Claim 25 delete Claim 26 delete Claim 27 delete Claim 28 delete Claim 29 delete Claim 30 delete Claim 31 delete Claim 32 delete Claim 33 delete Claim 34 delete Claim 35 delete Claim 36 delete Claim 37 delete Claim 38 delete Claim 39 delete Claim 40 delete Claim 41 delete Claim 42 delete Claim 43 delete Claim 44 delete Claim 45 delete Claim 46 delete Claim 47 delete Claim 48 delete Claim 49 delete Claim 50 delete Claim 51 delete Claim 52 delete Claim 53 delete Claim 54 delete Claim 55 delete Claim 56 delete Claim 57 delete Claim 58 delete Claim 59 delete Claim 60 delete Claim 61 delete Claim 62 delete Claim 63 delete Claim 64 delete Claim 65 delete Claim 66 delete Claim 67 delete Claim 68 delete Claim 69 delete Claim 70 delete Claim 71 delete Claim 72 delete Claim 73 delete Claim 74 delete Claim 75 delete Claim 76 delete Claim 77 delete Claim 78 delete Claim 79 delete Claim 80 delete Claim 81 delete Claim 82 delete Claim 83 delete

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