DC-DC voltage regulator and method for operating DC-DC voltage regulator

Abstract

The present application describes a DC-DC voltage regulator and a method for operating a DC-DC voltage regulator for converting an input voltage at an input port to one or more output voltages at respective output ports. In particular, the voltage regulator may include a first switching element, an inductive element, and a second switching element coupled in series between an input port and a reference voltage port; at least one negative output rail coupled between the first intermediate node and a respective output port; a capacitive element coupled between the second intermediate node and the third intermediate node; a third switching element coupled between the input port and a third intermediate node; at least one positive output rail coupled between the third intermediate node and a respective output port; a fourth switching element coupled between the third intermediate node and a reference voltage port; and a fifth switching element coupled between the first intermediate node and a reference voltage port.

Description

Technical Field

[0001] The present disclosure relates to the general field of power converter topologies, and more particularly, to power converter topologies commonly referred to as hybrid single inductor multiple output (SIMO) topologies. Background Art

[0002] The demand for compact voltage regulators in the mobile application market has increased recently due to the growing need to reduce unnecessary circuit board components in number or size to allow manufacturers of smart mobility solutions to integrate additional functions and reduce material costs.

[0003] SIMO structures have attracted a lot of interest because a single inductor in a compact environment and under a variable switching control scheme offers the benefits of reduced electromagnetic interference (EMI) and reduced board area. However, the limitation on the minimum coil size is mainly related to the maximum rated current in the coil. Large coils increase the size and cost of specific applications.

[0004] In some possible implementations, so-called hybrid SIMO topologies have been proposed, which typically use one flying capacitor for the positive rail or one flying capacitor for the negative rail. In general, the use of a flying capacitor results in a significant reduction in the inductor peak current.

[0005] Thus, in broad terms, the present disclosure is focused on techniques and / or topologies for switching direct current-to-direct current (DC-DC) voltage regulators that can achieve at least the same (or improved) functionality as conventional SIMO structures (hybrid or non-hybrid), while also supporting other operating modes that conventional (hybrid) SIMO topologies cannot provide. Methods of operating such switching DC-DC voltage regulators are also needed. Summary of the invention

[0006] In view of the above, the present disclosure generally provides a DC-DC voltage regulator and a method of operating the DC-DC voltage regulator.

[0007] According to one aspect of the present disclosure, a DC-DC voltage regulator (e.g., SIMO regulator) is provided for converting an input voltage (e.g., VIN) at an input port into one or more output voltages at a corresponding output port. Specifically, the voltage regulator may include a first switching element, an inductor element (e.g., an inductor) and a second switching element, and the first switching element, the inductor element and the second switching element may be coupled in series (e.g., directly or indirectly connected) between the input port and the reference voltage port. The reference voltage port may, for example, be connected to ground (GND) or VSS (or any other suitable reference voltage). The voltage regulator may also include at least one negative output rail, which may be coupled between a first intermediate node and a corresponding output port. More specifically, the first intermediate node may be arranged between the first switching element and the inductor element. Each negative output rail may be configured to generate a corresponding negative voltage (e.g., -5V, etc.) at a corresponding (negative) output port. The voltage regulator may also include a capacitive element (e.g., a capacitor), which may be coupled between a second intermediate node and a third intermediate node. More specifically, the second intermediate node may be arranged between the inductor element and the second switching element. The voltage regulator may also include a third switching element, which may be coupled between the input port and the third intermediate node. The voltage regulator may also include at least one positive output rail, which may be coupled between the third intermediate node and the corresponding output port. Similar to the negative output rail, each positive output rail may be configured to generate a corresponding positive voltage (e.g., +5V, etc.) at the corresponding (positive) output port. The voltage regulator may also further include a fourth switching element, which may be coupled between the third intermediate node and the reference voltage port. Finally, the voltage regulator may include a fifth switching element, which may be coupled between the first intermediate node and the reference voltage port. It is worth noting that any switching device mentioned in the present disclosure may be a transistor device, such as a metal oxide semiconductor field effect transistor (MOSFET), etc. In some possible (but certainly not limiting) implementations, the first switching element and the fourth switching element may be simple transistors, while the second switching element, the third switching element, and the fifth switching element may be implemented as back-to-back transistors (or sometimes also referred to as body switches). As can be understood and appreciated by those skilled in the art, depending on the implementation of the switching device, for example, in the example of MOSFET, the back-to-back configuration can refer to a configuration of two devices in series, and the drain terminals of the two devices are connected to each other or their source terminals are connected to each other. The result (and the most important characteristic) of this back-to-back configuration is that their body diodes point in opposite directions. Of course, any other suitable configuration or implementation can also be adopted according to various requirements and / or situations.

[0008] According to the above suggested configuration, the DC-DC voltage regulator (or more specifically, the hybrid SIMO regulator) of the present disclosure maintains all the advantages of the conventional hybrid SIMO topology over the conventional SIMO topology (e.g., lower inductor peak current, reduced conduction loss and core loss, thereby achieving higher efficiency). In addition, in particular, compared to the conventional hybrid SIMO topology (which requires a flying capacitor for the positive rail or a flying capacitor for the negative rail), the currently proposed implementation generally requires only a single flying capacitor for both the positive rail and the negative rail; and at the same time extends the positive rail operation all the way down to the input voltage. Other potential advantages and / or benefits will become apparent from the following description.

[0009] In some examples, the fourth switching element can be configured to couple the capacitive element in series with the inductive element for at least one negative output rail during operation of the voltage regulator. Additionally or alternatively, the fifth switching element can be configured to couple the capacitive element in series with the inductive element for at least one positive output rail during operation of the voltage regulator.

[0010] In some examples, the third switching element and the fifth switching element can be configured to charge the capacitive element through the inductive element during operation of the voltage regulator.

[0011] In some examples, the fourth switching element and the fifth switching element may be configured to magnetize the inductive element by using the capacitive element during operation of the voltage regulator.

[0012] In some examples, the first switching element and the fourth switching element can be configured to magnetize the inductive element by using the input voltage and the capacitive element simultaneously during operation of the voltage regulator. According to the proposed configuration, this may speed up the inductor magnetization time by a factor of two.

[0013] In some examples, the voltage regulator may include a first (operation) stage for charging the capacitive element.

[0014] In some examples, during the first stage of operation, the third switch element and the fifth switch element can be in an open state (e.g., a conductive state), and the first switch element, the second switch element, and the fourth switch element are in an off state (e.g., a non-conductive state), so that the capacitor element can be charged through the inductor element.

[0015] In some examples, the voltage regulator can include a second stage for magnetizing the inductive element.

[0016] In some examples, during the first operation of the second phase, the first switching element, the second switching element, and the third switching element may be in an on state, and the fourth switching element and the fifth switching element may be in an off state, so that the capacitor element can be charged and the inductor element can be magnetized by the input voltage.

[0017] In some examples, during the second operation of the second phase, the fourth and fifth switching elements may be in an on state, and the first, second, and third switching elements may be in an off state, so that the inductive element can be magnetized by the capacitive element.

[0018] In some examples, during the third operation of the second phase, the first switching element and the fourth switching element may be in an on state, and the second switching element, the third switching element, and the fifth switching element may be in an off state, so that the inductor element can be magnetized by the input voltage and the capacitive element. As previously described, this may result in a magnetization speed of the inductor that may be twice as fast.

[0019] In some examples, during operation of the third stage of the voltage regulator, the fourth switching element can be in an on state, and the first switching element, the second switching element, the third switching element, and the fifth switching element can be in an off state, thereby coupling the inductive element to a (e.g., preconfigured or predetermined) negative output rail and being connected in series with the capacitive element to a reference voltage port (e.g., ground, etc.).

[0020] In some examples, during operation of the fourth stage of the voltage regulator, the fifth switching element can be in an on state and the first switching element, the second switching element, the third switching element, and the fourth switching element can be in an off state, thereby coupling the inductive element to the reference voltage port and in series with the capacitive element to the positive output rail.

[0021] According to another aspect of the present disclosure, a method for operating a DC-DC voltage regulator (eg, a SIMO regulator) is provided, the DC-DC voltage regulator being used to convert an input voltage (eg, V IN) are respectively converted into one or more output voltages at the corresponding output port. In particular, the method may include coupling (e.g., directly or indirectly connecting) a first switching element, an inductor element (e.g., an inductor) and a second switching element in series between an input port and a reference voltage port. The reference voltage port may, for example, be connected to ground (GND) or VSS (or any other suitable reference voltage). The method may also include coupling at least one negative output rail between a first intermediate node and a corresponding output port. More specifically, the first intermediate node may be arranged between the first switching element and the inductor element. Each negative output rail may be configured to generate a corresponding negative voltage (e.g., -5V, etc.) at a corresponding (negative) output port. The method may also include coupling a capacitive element (e.g., a capacitor) between a second intermediate node and a third intermediate node. More specifically, the second intermediate node may be arranged between the inductor element and the second switching element. The method may also include coupling a third switching element between the input port and the third intermediate node. The method may also include coupling at least one positive output rail between the third intermediate node and the corresponding output port. Similar to the negative output rail, each positive output rail can be configured to generate a corresponding positive voltage (e.g., +5V, etc.) at the corresponding (positive) output port. The method can also include coupling a fourth switch element between the third intermediate node and the reference voltage port. Finally, the method can include coupling the first switch element between the first intermediate node and the reference pressure port. It is worth noting that any switch device mentioned in the present disclosure can be a transistor device, such as a MOSFET, etc.

[0022] Configured as described above, the DC-DC voltage regulator (or more specifically, hybrid SIMO regulator) of the present disclosure maintains all the advantages that the conventional hybrid SIMO topology has over the conventional SIMO topology. In addition, the currently proposed implementation generally requires only a single flying capacitor for both the positive rail and the negative rail, particularly compared to the conventional hybrid SIMO topology (which requires a flying capacitor for the positive rail or a flying capacitor for the negative rail); and at the same time extends the positive rail operation all the way down to the input voltage. Other potential advantages and / or benefits will become apparent from the following description.

[0023] In some examples, the method may further include, during the operation of the first stage of the voltage regulator for charging the capacitor element: switching the third switch element and the fifth switch element to an on state (e.g., a conductive state), and switching the first switch element, the second switch element, and the fourth switch element to an off state (e.g., a non-conductive state, for charging the capacitor unit through the inductor element).

[0024] In some examples, the method may further include, during a first operation of a second stage of a voltage regulator for magnetizing the inductive element: switching the first switching element, the second switching element, and the third switching element to an on state, and switching the fourth switching element and the fifth switching element to an off state, for charging the capacitive element and magnetizing the inductive element by the input voltage.

[0025] In some examples, the method may further include, during a second operation of the second phase of the voltage regulator for magnetizing the inductive element: switching the fourth switching element and the fifth switching element to an on state, and switching the first switching element, the second switching element, and the third switching element to an off state, for magnetizing the inductive element through the capacitive element.

[0026] In some examples, the method may further include, during a third operation of the second stage of the voltage regulator for magnetizing the inductive element: switching the first switching element and the fourth switching element to an on state, and switching the second switching element, the third switching element, and the fifth switching element to an off state, for magnetizing the inductive element by the input voltage and the capacitive element.

[0027] In some examples, the method may further include, during operation of the third stage of the voltage regulator: switching the fourth switching element to an on state, and switching the first switching element, the second switching element, the third switching element, and the fifth switching element to an off state, for coupling the inductive element to the negative output rail and in series with the capacitive element to the reference voltage port.

[0028] In some examples, the method may further include, during operation of a fourth stage of the voltage regulator: switching the fifth switching element to an on state, and switching the first switching element, the second switching element, the third switching element, and the fourth switching element to an off state, for coupling the inductive element to the reference voltage port and in series with the capacitive element to the positive output rail.

[0029] In some examples, the method may further include, in order to generate a positive output voltage greater than twice the input voltage: repeatedly operating the voltage regulator according to a predetermined operating sequence, the operating sequence including: switching the third switch element and the fifth switch element to the on state, and switching the first switch element, the second switch element, and the fourth switch element to the off state; switching the first switch element and the fourth switch element to the on state, and switching the second switch element, the third switch element, and the fifth switch element to the off state; and switching the first switch element to the on state, and switching the second switch element, the third switch element, the fourth switch element, and the fifth switch element to the off state.

[0030] In some examples, the method may further include, in order to generate a positive output voltage greater than the input voltage and less than twice the input voltage: repeatedly operating the voltage regulator according to a predetermined operating sequence, the operating sequence including: switching the third switch element and the fifth switch element to the on state, and switching the first switch element, the second switch element, and the fourth switch element to the off state; switching the first switch element to the on state, and switching the second switch element, the third switch element, the fourth switch element, and the fifth switch element to the off state; and switching the fifth switch element to the on state, and switching the first switch element, the second switch element, the third switch element, and the fourth switch element to the off state.

[0031] In some examples, the method may further include, in order to generate a negative output voltage having an absolute amplitude greater than the input voltage: repeatedly operating the voltage regulator according to a predetermined operating sequence, the predetermined operating sequence including: switching the third switch element and the fifth switch element to the on state, and switching the first switch element, the second switch element, and the fourth switch element to the off state; switching the fourth switch element and the fifth switch element to the on state, and switching the first switch element, the second switch element, and the third switch element to the off state; and switching the fourth switch element to the on state, and switching the first switch element, the second switch element, the third switch element, and the fifth switch element to the off state.

[0032] In some examples, the method may further include, in order to generate a negative output voltage having an absolute amplitude greater than 0 and less than the input voltage: repeatedly operating the voltage regulator according to a predetermined operating sequence, the predetermined operating sequence including: switching the third switch element and the fifth switch element to the on state, and switching the first switch element, the second switch element, and the fourth switch element to the off state; switching the second switch element to the on state, and switching the first switch element, the third switch element, the fourth switch element, and the fifth switch element to the off state; and switching the second switch element and the third switch element to the on state, and switching the first switch element, the fourth switch element, and the fifth switch element to the off state.

[0033] The details of the disclosed method may be implemented as a device (e.g., a SIMO regulator) suitable for performing some or all of the steps of the method, and vice versa, as will be understood and appreciated by those skilled in the art. In particular, it should be understood that the method according to the present disclosure relates to a method of operating a circuit according to the above-described embodiments and variations thereof, and corresponding statements made about the circuit are equally applicable to the corresponding method.

[0034] It should also be understood that in this application document, the term "coupled" or "coupled to" refers to elements that are in electrical communication with each other, whether these elements are directly connected (e.g., via wires) or connected in some other way (e.g., indirectly). It is worth noting that an example of being coupled is being connected. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Example embodiments of the present disclosure are explained below with reference to the accompanying drawings, in which like reference numerals indicate the same or similar elements, and in which:

[0036] Figure 1 Schematically shows an example of a hybrid SIMO regulator topology with one negative output rail and one positive output rail,

[0037] Figure 2 Schematically shows an example of a DC-DC voltage regulator topology according to an embodiment of the present disclosure,

[0038] Figure 3 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of a first operation of the first stage of the DC-DC voltage regulator is shown,

[0039] Figure 4 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the second operation of the first stage of the DC-DC voltage regulator is shown,

[0040] Figure 5 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the first operation of the second stage of the DC-DC voltage regulator is shown,

[0041] Figure 6 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the second operation of the second stage of the DC-DC voltage regulator is shown,

[0042] Figure 7 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the third operation of the second stage of the DC-DC voltage regulator is shown,

[0043] Figure 8 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the first operation of the third stage of the DC-DC voltage regulator is shown,

[0044] Fig. 9 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the second operation of the third stage of the DC-DC voltage regulator is shown,

[0045] Fig.10 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the first operation of the fourth stage of the DC-DC voltage regulator is shown,

[0046] Fig.11 The schematic diagram shows the embodiment according to the present disclosure. Figure 2 An example of the second operation of the fourth stage of the DC-DC voltage regulator is shown, and

[0047] Fig.12 A flowchart schematically illustrates an example of a method of operating a DC-DC voltage regulator according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] As described above, unless otherwise indicated, the same or similar reference numerals in the present disclosure may indicate the same or similar elements, so that repeated descriptions thereof may be omitted for the sake of brevity. In addition, any switching element / device mentioned in the present disclosure may be a transistor device, such as a MOSFET, or any other suitable switching device. In some figures, the switching devices may be simplified, but these switching devices should be understood to be the same or similar switching devices as those shown in other figures.

[0049] As mentioned above, in some possible implementations of the conventional hybrid SIMO topology, a flying capacitor for the negative rail or a flying capacitor for the positive rail is provided in the conventional hybrid SIMO topology.

[0050] For ease of understanding, Figure 1 An example of an implementation 100 of such a conventional hybrid SIMO regulator is schematically shown.

[0051] In particular, Figure 1 In the exemplary SIMO regulator 100, the regulator 100 includes a series coupled input voltage level (V IN ) and a predetermined voltage level, a high-side switching device (e.g., a transistor device, a MOSFET, etc.) 101, an indicating element (e.g., an inductor) 105, and a boost low-side switching device (e.g., a transistor device). The predetermined voltage level can be, for example, VSS or ground (GND) or any other suitable reference voltage level. The regulator 100 also includes a negative output rail and a positive output rail. The negative output rail includes a low-side switching device (e.g., a transistor device) 121 and is coupled between the first intermediate node 111 and the (negative) output node, where a negative output voltage level (V NEG). The first intermediate node 111 is disposed between the high-side switch device 101 and the inductive element 105. Similarly, the positive output rail includes a boost high-side switch device (e.g., a transistor device) 131 and is coupled between the second intermediate node 113 and the (positive) output node, where a positive output voltage level (V POS ). The second intermediate node 113 is arranged between the inductive element 105 and the boost low-side switching device 131. In addition, a capacitive element (e.g., a flying capacitor) 104 and a charging switch device 102 are provided to reduce the voltage drop across the coils of the inductive element 105 and the low-side switching device 121. In this arrangement, it can be considered that the flying capacitor 104 is configured for the negative rail. Specifically, the capacitive element 104 and the charging switch element 102 are coupled in series between the first intermediate node 111 and a predetermined voltage level (e.g., VSS or GND). The second intermediate node 112 is arranged between the capacitive element 104 and the charging switch element 102. As will be appreciated by those skilled in the art, the voltage regulator may also include various capacitors (not specifically marked) coupled between various output ports and ground. Incidentally, it is worth noting that in order to operate the switching device, the regulator may also include a control unit (not shown in the figure) for generating corresponding control signals.

[0052] Figure 1 The operation of the conventional hybrid SIMO regulator 100 is generally considered to be easily understood or comprehended by those skilled in the art, and therefore, for the sake of brevity, the operation of the conventional hybrid SIMO regulator 100 is not described in detail herein.

[0053] Reference now Figure 2 , Figure 2 An example of a DC-DC voltage regulator topology (or more specifically, a hybrid SIMO regulator topology) 200 according to an embodiment of the present disclosure is schematically shown.

[0054] Broadly speaking, the DC-DC voltage regulator topologies proposed in the present disclosure share a similar arrangement / architecture of switching elements that can be configured to charge the flying capacitor and all switching elements connected to the inductor. Therefore, for the sake of brevity, a repeated description thereof may be omitted. Most importantly, the present disclosure generally suggests adding two more switching elements (more specifically, Figure 2 The switching elements 204 and 205 shown in the figure can be configured to provide mixed mode operation for both the positive and negative rails using only one external flying capacitor. Generally speaking, this means reducing the inductor peak current, thereby reducing conduction losses and core losses, and thus achieving higher efficiency. In particular, as described above, compared with the above reference Figure 1Unlike the conventional hybrid SIMO topology, the hybrid SIMO implementation proposed in the present disclosure supports both negative and positive rails requiring a single flying capacitor; and at the same time extends the positive rail operation all the way down to the input voltage (V IN ).

[0055] More specifically, if Figure 2 As shown in the exemplary embodiment 200, the first switch element 201, the inductive element (eg, inductor) 206 and the second switch element 202 may be configured to be serially coupled (eg, directly or indirectly connected) at the input port (V IN ) and a reference voltage terminal (e.g., GND).

[0056] The voltage regulator 200 further includes at least one negative output rail, which may be coupled between the first intermediate node 211 and the corresponding output port. More specifically, the first intermediate node 221 may be considered to be arranged between the first switching element 201 and the inductive element 206. Each negative output rail may include a corresponding switching element 221-1, 221-2, ..., 221-j, and may be arranged to generate a corresponding negative voltage V at a corresponding (negative) output port. NEG1 ,V NEG2 ,…,V NEGj (For example, -5V, etc.).

[0057] Similarly, the voltage regulator 200 further includes at least one positive output rail that can be coupled between the third intermediate node 213 and the corresponding output port. Similar to the negative output rails described above, each positive output rail can include a corresponding switching element 231-1, 231-2, ..., 231-k, and can be configured to generate a corresponding positive voltage V at the corresponding (positive) output port. POS1 ,V POS2 ,…,V POSk (For example, +5V, etc.).

[0058] The voltage regulator 200 further includes a capacitive element (eg, capacitor) 207, which may be arranged to be coupled between the second intermediate node 212 and the third intermediate node 213. More specifically, the second intermediate node may be considered to be arranged between the inductive element 206 and the second switching element 202.

[0059] The voltage regulator 200 further includes a third switching element 203 coupled between the input port and a third intermediate node 213 .

[0060] Finally, the voltage regulator 200 includes a fourth switching element 204 coupled between the third intermediate node 213 and the reference voltage port; and a fifth switching element 205 coupled between the first intermediate node 211 and the reference voltage port.

[0061] As described above, in some possible (but certainly non-limiting) cases, the first switch element 201 and the fourth switch element 204 can be implemented as simple transistors, while the second switch element 202, the third switch element 203 and the fifth switch element 205 can be implemented as back-to-back transistors (or sometimes also referred to as body switches). As can be understood and appreciated by those skilled in the art, depending on the implementation of the switching device, for example, in the example of MOSFET, the back-to-back configuration can refer to a configuration of two devices in series, and the drain terminals of the two devices are connected to each other or their source terminals are connected to each other. The result of this back-to-back configuration (and the most important characteristic) is that their body diodes point in opposite directions. Of course, any other suitable configuration or implementation method can also be adopted according to various requirements and / or situations.

[0062] As configured as described above, the DC-DC voltage regulator 200 maintains all the advantages of the conventional hybrid SIMO topology over the conventional SIMO topology (e.g., lower inductor peak current, reduced conduction loss and core loss, thereby achieving higher efficiency). In addition, in particular, compared with the conventional hybrid SIMO topology (e.g., reference Figure 1 Compared to the topology described in the previous embodiment, which requires either a flying capacitor for the positive rail or a flying capacitor for the negative rail, the presently proposed embodiment 200 requires only a single flying capacitor for both the positive and negative rails; and at the same time extends the positive rail operation all the way down to the input voltage.

[0063] In particular, as described in detail below with reference to the accompanying drawings, the provision of the (newly introduced) fourth switching element 204 can be understood as enabling the flying capacitor 207 to be coupled (connected) in series with the inductor 206 for the negative rail during certain operations of the voltage regulator 200. In addition, the provision of the fourth switching element 204 can also be configured to be connected to the negative rail by connecting the inductor 206 to V NEGn and connected in series with the flying capacitor 207 to GND to enable the voltage V across the inductor 204 IN +V NEGn (where n∈[1,j]).

[0064] On the other hand, the provision of the (newly introduced) fifth switching element 205 can be understood as enabling the flying capacitor 207 to be coupled (connected) in series with the inductor 206 for the positive rail during certain operations of the voltage regulator 200. In addition, the provision of the fifth switching element 205 can also be configured to be connected in series with the inductor 206 between GND and with the flying capacitor to V. POSn To enable the voltage V across the inductor 204 IN -V POSn (where n∈[1,k]).

[0065] Furthermore, the provision of the fourth and fifth switching elements 204 and 205 generally enables magnetization of the inductor 206 by the flying capacitor 207 during certain operations of the voltage regulator 200 .

[0066] Furthermore, providing the (newly introduced) fourth switching element 204 and / or the (newly introduced) fifth switching element 205 may also enable operations that are not possible in conventional (hybrid) SIMO regulator topologies when operated in combination with one or more other existing switching elements (e.g., switching elements 201, 202, or 203).

[0067] For example, the provision of the first switching element 201 and the fourth switching element may be configured so that the power supply can be simultaneously supplied through the source (V IN ) and the flying capacitor 208 magnetize the inductor 206, which in turn can make the inductor magnetization time twice as fast.

[0068] On the other hand, the provision of the third switching element 203 and the fifth switching element 205 may be configured to enable charging of the flying capacitor 207 through the inductor 206, thereby significantly reducing the inductor voltage ringing, while reusing the remaining energy of the inductor to recharge the flying capacitor.

[0069] Of course, as those skilled in the art will understand and appreciate, the above is provided for illustrative purposes only and should not be construed as constituting any type of limitation. Any other suitable configuration and / or operation of the voltage regulator (switching element) may be implemented according to various requirements and / or circumstances. Figures 3 to 11 With the description of the present invention, some of these possible further configurations and / or operations and the corresponding benefits / advantages associated therewith may become more apparent.

[0070] It is worth noting that for better explanation and understanding, Figures 3 to 11 The description is organized as follows. First, the conventional hybrid SIMO regulator 100 ( Figure 1 The voltage regulator 200 (shown) is not supported Figure 2 The diagram of the operation phase (or mode) shown in FIG. Figure 4 , Figure 6 , Figure 7 , Fig. 9 and Fig.10 Then, the conventional hybrid SIMO regulator 100 ( Figure 1 The remaining operating phases / modes of the voltage regulator 200 (shown) are supported (or partially supported) by FIG.

[0071] first, Figure 4Schematically shows how the third switching element 203 and the fifth switching element 205 can be jointly configured to charge the flying capacitor 207 through the inductor 206 (as shown by the arrows). In particular, in this operating phase of the voltage regulator 200 (as shown in FIG. Figure 4 ), the third switching element 203 and the fifth switching element 205 are set to the on (conducting) state, while the first switching element 201, the second switching element 202 and the fourth switching element 204 are set to the off (non-conducting) state, so that the capacitor 207 is charged through the inductor 206. By the way, it can be understood that in this operation phase (for charging the capacitor), all switching elements in the negative rail and the positive rail are in the off state. As the configuration proposed above, in particular by reusing the residual energy in the inductor 206 to recharge the flying capacitor 207, the voltage ringing of the inductor can be significantly reduced.

[0072] Next, Figure 6 Schematically shows how the fourth switching element 204 and the fifth switching element 205 can be jointly configured to enable another mode of the magnetizing inductor 206 by using the flying capacitor 207 as a potential source. In particular, as shown by the arrows, in this operating phase (eg Figure 6 ), the fourth and fifth switching elements 204 and 205 are in the on-state, while the first, second and third switching elements 201, 202 and 203 are in the off-state, so that the inductor 206 can be magnetized by the capacitor 207. It is worth noting that, compared with the operation phase for magnetizing the inductor in the conventional SIMO topology, in the proposed scheme of the present disclosure, no (high) current from the input / source is required, because the inductor is usually magnetized by the energy of the capacitor, resulting in a reduction of EMI (electromagnetic interference). It is worth noting further that, in a broad sense, when using |V for the negative rail NEGn |>V IN The mixed operation mode and the V POSn <2×V IN When the boost operation mode is used, the operation of the diagram can generally utilize a lower ohmic path (for example, when the fourth and fifth switching elements 204 and 205 can be implemented by using N-type MOSFETs, etc.) and fewer switching events.

[0073] Figure 7 The schematic diagram shows how the fourth switching element 204 and the first switching element are configured to connect the inductor 206 to V IN and GND and in series with the flying capacitor 207 to enable twice the voltage V across the inductor IN More specifically, in this operation phase (such as Figure 7 ), the first switch element 201 and the fourth switch element 204 are in the on state, while the second switch element 202, the third switch element 203 and the fifth switch element 205 are in the off state, thereby magnetizing the inductor 206 through the input voltage and the capacitor 207. In general, twice the input voltage can be understood to result in (approximately) twice as fast a reaction to the same peak current, which in turn can result in lower conduction losses.

[0074] also, Fig. 9 Schematically shows how the fourth switching element 204 is configured to connect the inductor 206 to the negative rail ( Fig. 9 In the example of NEG1 ) and connected in series with the flying capacitor 207 to GND to enable the voltage V across the inductor 206 IN +V NEGn , thereby enabling the negative rail |V NEGn |>V IN More specifically, in this operation phase (such as Fig. 9 As shown in P2n in FIG, the fourth switch element 204 is in the on state, and the first switch element 201, the second switch element 202, the third switch element 203 and the fifth switch element 205 are in the off state, thereby coupling the inductor to the negative output rail and connecting the capacitor 207 in series to the reference voltage port (GND).

[0075] also, Fig.10 The schematic diagram shows how the fifth switching element 205 is configured to be connected to either positive rail by connecting the inductor 206 between GND and in series with the flying capacitor 207 ( Fig.10 In the example of POS1 ) to enable the voltage V across the inductor 206 IN -V POSn More specifically, in this operation phase (such as Fig.10 ), the fifth switching element 205 is in the on state, while the first switching element 201, the second switching element 202, the third switching element 203 and the fourth switching element 204 are in the off state, thereby coupling the inductor 206 to the reference voltage port (GND) and connecting it in series with the capacitor 207 to the positive output rail. By the way, it may be worth mentioning that in this stage, the flying capacitor 207 is used to demagnetize the inductor 206.

[0076] As mentioned above, the above-mentioned operation phases / modes are generally not supported for conventional SIMO topologies nor conventional hybrid SIMO topologies (e.g. Figure 1or in other words, no corresponding phase / mode can be found in the operating phase / mode of the traditional (hybrid) SIMO topology.

[0077] Next, referring to the remaining drawings, a brief description will be given of the operation Figure 2 Other possible phases / modes of the voltage regulator 200 will also be described, if applicable, with potential further advantages associated therewith.

[0078] first, Figure 3 Another possible hybrid phase 0 operation is schematically depicted for charging the flying capacitor 207 (at Figure 3 It is represented as P0a, and Figure 4 As will be understood and appreciated by those skilled in the art, generally speaking, a flying capacitor charging phase (generally indicated as P0) may always be applied between PFM pulses. However, it is worth emphasizing that, as described above with reference to Figure 4 As described above, utilizing P0b can significantly eliminate the ringing and can also reuse the remaining inductor energy to (re)charge the flying capacitor, especially when the inductor current is negative.

[0079] Figure 5 (Together with the previously shown Figure 6 and Figure 7 ) schematically depicts the phase 1 operation (generally indicated as P1) for magnetizing the inductor 206. In general, typically, V IN The magnetizing inductor 206, such as Figure 5 As shown (indicated as P1a), or from the flying capacitor 207 magnetizing the inductor 206, as Figure 6 shown (denoted as P1b).

[0080] It is worth noting that a third possible operation (such as Figure 7 That is, the inductor 206 can now be switched from V IN and the flying capacitor 207 is magnetized. As previously mentioned, this mode can provide twice as fast inductor magnetization (or in other words, twice the magnetizing current slope of P1a or P1b). In general, this operating phase can be considered particularly suitable for having a voltage from V IN To V OUT In the case of large voltage differences (for example, at V IN_min and V OUT_max place).

[0081] For the sake of completeness, reference will be made to Figure 8 and Fig.11 Two other possible stages of operation (denoted as P2p and P3n) are briefly discussed.

[0082] Specifically, Figure 8 As shown, mode P2p can be considered suitable for charging any positive rail, especially at V POSn >2×V IN To achieve this, the first switch element 201 is set to an on state, while the second switch element 202, the third switch element 203, the fourth switch element 204 and the fifth switch element 205 are set to an off state, thereby coupling the inductor 206 in series to the positive rail (e.g., through the V of the switch element 231-1) via the capacitor 207. POS1 ).

[0083] Similarly, if Fig.11 As shown, mode P3n can be considered to be suitable for charging any negative rail (and also for capacitors), especially when |V NEGn | <V IN To achieve this, the second switching element 202 and the third switching element 203 are set to the on state, while the first switching element 201, the fourth switching element 204 and the fifth switching element 205 are set to the off state, thereby connecting the inductor 206 in series to the negative rail (for example, through the V NEG1 ) and the ground terminal GND. At the same time, as shown by the arrow, the flying capacitor 207 is charged from the source input terminal.

[0084] It is worth noting that, even if not explicitly shown in the drawings, as those skilled in the art can understand and appreciate, in order to properly operate the switching devices therein, the voltage regulator topology structure may further include a suitable control unit for generating corresponding control signals.

[0085] As described above, the techniques proposed in the present disclosure provide significant improvements in both conventional SIMO and conventional hybrid SIMO topologies. For illustrative purposes only, the following Table 1 schematically summarizes several (non-exhaustive) advantages / advantages of the present disclosure over conventional SIMO implementations and conventional hybrid SIMO implementations.

[0086]

[0087]

[0088] Table 1. Comparison between the present disclosure and conventional (hybrid) SIMO.

[0089] As can be seen from the above summary table, in general, conventional hybrid SIMOs do not support some functions that conventional SIMOs support, and vice versa. However, the technology proposed in this disclosure generally supports all of these features.

[0090] at last, Fig.12 1 is a flow chart schematically illustrating an example of a method 1200 of operating a DC-DC voltage regulator (eg, a SIMO regulator) according to an embodiment of the present disclosure. The DC-DC voltage regulator may correspond to Figure 2 The voltage regulator 200 shown. The method 1200 includes, at step S1210, coupling a first switch element, an inductor element (e.g., an inductor) and a second switch element in series (e.g., directly or indirectly connected) between an input port and a reference voltage port. The reference voltage port can be connected to ground (GND) or VSS (or any other suitable reference voltage), for example. The method 1200 also includes, at step S1220, coupling at least one negative output rail between a first intermediate node and a corresponding output port. Specifically, the first intermediate node can be set between the first switch element and the inductor element. Each negative output rail can be configured to generate a corresponding negative voltage (e.g., -5V, etc.) at a corresponding (negative) output port. The method 1200 also includes, at step S1230, coupling a capacitive element (e.g., a capacitor) between a second intermediate node and a third intermediate node. Specifically, the second intermediate node can be set between the inductor element and the second switch element. The method 1200 also includes, at step S1240, coupling a third switch element between the input port and the third intermediate node. In addition, the method 1200 includes, at step S1250, coupling at least one positive output rail between a third intermediate node and a corresponding output port. Similar to the negative output rail, each positive output rail can be configured to generate a corresponding positive voltage (e.g., +5V, etc.) at a corresponding (positive) output port. In addition, the method also includes, at step S1260, coupling a fourth switching element between a second intermediate node and a reference voltage port. Finally, the method 1200 also includes, at step S1270, coupling a fifth switching element between a first intermediate node and a reference voltage port. It is noteworthy that, as can be understood and appreciated by those skilled in the art, any switching element / device mentioned in the present disclosure can be a transistor device, such as a field effect transistor (FETs), a MOSFET, etc., or any other suitable switching device.

[0091] It is worth noting that, broadly speaking, the hybrid SIMO topology proposed throughout the present disclosure allows for great flexibility in the order of phases, which in turn allows for providing stable negative and / or positive output rails and maintaining a stable flying capacitor voltage. For illustrative purposes only, some non-limiting examples of possible phase orders supported by the hybrid SIMO implementation proposed by the present disclosure are listed below.

[0092] As an example of a first possible sequence of phases (e.g., a normal track V POS1 As an example),

[0093] If V POS1 >2×V IN , then the phase sequence can be configured (in a repetitive manner):

[0094] …P0b->P1c->P2p…(returns to P0b);

[0095] On the other hand, if V IN <V POS1 <2x V IN , then the phase sequence can be configured (in a repetitive manner):

[0096] …P0b->P2p->P3p…(returns to P0b).

[0097] As an example of a second possible phase sequence (e.g., negative rail V NEGn Can be used as an example):

[0098] If |V NEGn |>V IN , then the phase sequence can be configured (in a repetitive manner):

[0099] …P0b->P1b->P2n…(return to P0b);

[0100] On the other hand, if 0<|V NEGn | <V IN , then the phase sequence can be configured (in a repetitive manner):

[0101] …P0b->P2n->P3n…(returns to P0b).

[0102] As an example of a third possible phase sequence, particularly where the voltage across the inductor may be close to zero (or slightly positive or slightly negative), causing the inductor current to be (nearly) "flat" during the P2p phase and the P2n phase, that is:

[0103] If |V NEGn |≈V IN , then the phase sequence can be configured (in a repetitive manner):

[0104] …P0b->P1b->P2n->P3n…(returns to P0b).

[0105] Similarly, this can also be applied to the positive track. That is, as an example of the fourth possible stage ordering:

[0106] If V POSn ≈2×V IN , then the phase sequence can be configured (in a repetitive manner):

[0107] …P0b->P1c->P2p->P3p…(returns to P0b).

[0108] It is worth noting that in the examples shown above, the phase sequence may appear to always start (and restart) with phase P0b. This may be simply because, as described above, in such phase P0b, the remaining energy in the inductor is reused to charge the flying capacitor. Of course, as can be understood and appreciated by those skilled in the art, any other suitable phase operation sequence may be adopted according to various embodiments and / or requirements. In general, the selection of the phase sequence may take into account at least one of the number of transistor switching, fast response, reduced electromagnetic interference, utilization (reuse) of energy (e.g., in the flying capacitor), etc.

[0109] It should also be noted that the above-mentioned device features correspond to corresponding method features, however, for the sake of brevity, these method features may not be clearly described. The disclosure of this document is considered to extend to these method features as well. Specifically, the disclosure is understood to relate to methods of operating the above-mentioned circuits, and / or to providing and / or arranging individual elements of these circuits.

[0110] It should be further noted that the description and drawings merely illustrate the principles of the proposed circuits and methods. Those skilled in the art will be able to implement various arrangements that, although not explicitly described or shown herein, embody the principles of the present invention and are included within the spirit and scope of the present invention. In addition, all examples and embodiments described in this document are primarily and explicitly intended to be used for explanatory purposes only, to help the reader understand the principles of the proposed methods. In addition, all statements of the principles, aspects, and embodiments of the present invention and their specific examples provided herein are intended to include their equivalents.

Claims

1. A DC-DC voltage regulator for converting an input voltage at an input port into one or more output voltages at a corresponding output port, the voltage regulator comprising: a first switch element, an inductor element, and a second switch element coupled in series between the input port and the reference voltage port, at least one negative output rail coupled between a first intermediate node and a corresponding output port, wherein the first intermediate node is disposed between the first switching element and the inductive element, a capacitive element coupled between a second intermediate node and a third intermediate node, wherein the second intermediate node is disposed between the inductive element and the second switching element, a third switching element coupled between the input port and the third intermediate node, at least one positive output rail coupled between said third intermediate node and a corresponding output port, a fourth switch element coupled between the third intermediate node and the reference voltage port, and A fifth switching element is coupled between the first intermediate node and the reference voltage port.

2. The voltage regulator according to claim 1, wherein The fourth switching element is configured to couple the capacitive element in series with the inductive element of the at least one negative output rail during operation of the voltage regulator; and / or The fifth switching element is configured for coupling the capacitive element in series with the inductive element of the at least one positive output rail during operation of the voltage regulator.

3. The voltage regulator according to claim 1, wherein The third switching element and the fifth switching element are configured to charge the capacitive element through the inductive element during operation of the voltage regulator.

4. The voltage regulator according to claim 1, wherein The fourth switching element and the fifth switching element are configured to magnetize the inductive element by using the capacitive element during operation of the voltage regulator.

5. The voltage regulator according to claim 1, wherein The first switching element and the fourth switching element are configured to magnetize the inductive element by using the input voltage and the capacitive element during operation of the voltage regulator.

6. The voltage regulator of claim 1, comprising a first stage for charging the capacitive element.

7. The voltage regulator according to claim 6, wherein: During the first phase of operation, The third switching element and the fifth switching element are in an on state, and the first switching element, the second switching element, and the fourth switching element are in an off state, so that the capacitance element can be charged through the inductance element.

8. The voltage regulator of claim 1, comprising a second stage for magnetizing the inductive element.

9. The voltage regulator according to claim 8, wherein: During the first operation of the second phase, The first switching element, the second switching element, and the third switching element are in an on state, and the fourth switching element and the fifth switching element are in an off state, so that the capacitance element can be charged and the inductance element can be magnetized by the input voltage.

10. The voltage regulator according to claim 8, wherein: During the second operation of the second phase, the fourth switching element and the fifth switching element are in an on state, and the first switching element, the second switching element, and the third switching element are in an off state, so that the inductance element is magnetized by the capacitance element.

11. The voltage regulator according to claim 8, wherein: During the third operation of the second phase, The first switching element and the fourth switching element are in an on state, and the second switching element, the third switching element, and the fifth switching element are in an off state, so that the inductance element is magnetized by the input voltage and the capacitance element.

12. The voltage regulator according to claim 1, wherein: During the third stage of operation of the voltage regulator, The fourth switch element is in the on state, and the first switch element, the second switch element, the third switch element and the fifth switch element are in the off state, thereby coupling the inductor element to the negative output rail and being connected in series with the capacitive element to the reference voltage port.

13. The voltage regulator according to claim 1, wherein: During the fourth stage of operation of the voltage regulator, The fifth switching element is in an on state, and the first switching element, the second switching element, the third switching element and the fourth switching element are in an off state, thereby coupling the inductive element to the reference voltage port and in series with the capacitive element to a positive output rail.

14. A method for operating a DC-DC voltage regulator for converting an input voltage at an input port into one or more output voltages at respective output ports, the method comprising: A first switch element, an inductor element and a second switch element are coupled in series between the input port and the reference voltage port, coupling at least one negative output rail between a first intermediate node and a corresponding output port, wherein the first intermediate node is disposed between the first switching element and the inductive element, coupling a capacitive element between a second intermediate node and a third intermediate node, wherein the second intermediate node is disposed between the inductive element and the second switching element, coupling a third switching element between the input port and the third intermediate node, coupling at least one positive output rail between said third intermediate node and a corresponding output port, coupling a fourth switch element between the third intermediate node and the reference voltage port, and A fifth switching element is coupled between the first intermediate node and the reference voltage port.

15. The method of claim 14, further comprising during operation of a first stage of the voltage regulator for charging the capacitive element: The third switching element and the fifth switching element are switched to an on state, and the first switching element, the second switching element, and the fourth switching element are switched to an off state, so as to charge the capacitance element through the inductance element.

16. The method of claim 14, further comprising, during a first operation of a second phase of the voltage regulator for magnetizing the inductive element: The first switching element, the second switching element, and the third switching element are switched to an on state, and the fourth switching element and the fifth switching element are switched to an off state, so as to charge the capacitance element and magnetize the inductance element by the input voltage.

17. The method of claim 14, further comprising during a second operation of a second phase of the voltage regulator for magnetizing the inductive element: The fourth switching element and the fifth switching element are switched to an on state, and the first switching element, the second switching element, and the third switching element are switched to an off state, for magnetizing the inductance element through the capacitance element.

18. The method of claim 14, further comprising during a third operation of the second phase of the voltage regulator for magnetizing the inductive element: The first switching element and the fourth switching element are switched to an on state, and the second switching element, the third switching element, and the fifth switching element are switched to an off state, for magnetizing the inductance element by the input voltage and the capacitance element.

19. The method of claim 14, further comprising during operation of the third stage of the voltage regulator: The fourth switch element is switched to an on state, and the first switch element, the second switch element, the third switch element and the fifth switch element are switched to an off state, so as to couple the inductor element to a negative output rail and to be connected in series with the capacitive element to the reference voltage port.

20. The method of claim 14, further comprising during operation of a fourth stage of the voltage regulator: The fifth switch element is switched to an on state, and the first switch element, the second switch element, the third switch element and the fourth switch element are switched to an off state, so as to couple the inductor element to the reference voltage port and to be connected in series with the capacitive element to a positive output rail.

21. The method of claim 14, further comprising: generating a positive output voltage greater than twice the input voltage: Repeating the operation of the voltage regulator according to a predetermined operation sequence, the predetermined operation sequence comprising: Switching the third switching element and the fifth switching element to an on state, and switching the first switching element, the second switching element, and the fourth switching element to an off state; Switching the first switching element and the fourth switching element to the on state, and switching the second switching element, the third switching element, and the fifth switching element to the off state; as well as The first switching element is switched to the on-state, and the second switching element, the third switching element, the fourth switching element, and the fifth switching element are switched to the off-state.

22. The method of claim 14, further comprising generating a positive output voltage greater than the input voltage but less than twice the input voltage: Repeating the operation of the voltage regulator according to a predetermined operation sequence, the predetermined operation sequence comprising: Switching the third switching element and the fifth switching element to an on state, and switching the first switching element, the second switching element, and the fourth switching element to an off state; Switching the first switching element to the on state, and switching the second switching element, the third switching element, the fourth switching element, and the fifth switching element to the off state; as well as The fifth switching element is switched to the on-state, and the first switching element, the second switching element, the third switching element, and the fourth switching element are switched to the off-state.

23. The method of claim 14, further comprising generating a negative output voltage having an absolute amplitude greater than zero but less than the input voltage: Repeating the operation of the voltage regulator according to a predetermined operation sequence, the predetermined operation sequence comprising: Switching the third switching element and the fifth switching element to an on state, and switching the first switching element, the second switching element, and the fourth switching element to an off state; Switching the fourth switching element and the fifth switching element to the on state, and switching the first switching element, the second switching element, and the third switching element to the off state; as well as The fourth switching element is switched to the on-state, and the first switching element, the second switching element, the third switching element, and the fifth switching element are switched to the off-state.

24. The method of claim 14, further comprising generating a negative output voltage having an absolute amplitude greater than zero but less than the input voltage: Repeating the operation of the voltage regulator according to a predetermined operation sequence, the predetermined operation sequence comprising: Switching the third switching element and the fifth switching element to an on state, and switching the first switching element, the second switching element, and the fourth switching element to an off state; Switching the fourth switching element to the on state, and switching the first switching element, the second switching element, the third switching element, and the fifth switching element to the off state; as well as The second switching element and the third switching element are switched to the on-state, and the first switching element, the fourth switching element, and the fifth switching element are switched to the off-state.

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