Integration circuit, control method of integration circuit, and switching controller

Abstract

An integration circuit, a control method of the integration circuit, and a switch controller are provided. The integration circuit includes a current source, a capacitor connected in series with the current source, a voltage source bias connected in series with the capacitor, a switch configured to connect a first node between the current source and the capacitor and a second node between the capacitor and the voltage source bias, and a switch control logic unit configured to control on / off operation of the switch, wherein an integration operation is performed by the current source and the capacitor.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of Korean Patent Application No. 10-2019-0087916, filed on July 19, 2019 with the Korean Intellectual Property Office under 35U.SC119(a), the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] The following description relates to integrator circuits, as well as control methods and devices. Background Technology

[0004] Technologies are currently being developed to minimize the size of signal processing devices such as analog-to-digital (A / D) converters, light-emitting diodes (LEDs), backlight driving devices, and display devices, and specifically, to design these devices using thin forming factors. Additionally, it is desirable to reduce the size of various components installed within these devices.

[0005] Alternatively, it is preferable to minimize the size of the device in order to reduce power consumption caused by a large device, or to install more components (e.g., chips or microchips) to diversify the functionality of the device.

[0006] The device can be equipped with various components or chips, one of which can be an integrating circuit. An integrating circuit may include two current sources, two capacitors connected in series with each of the current sources, and a comparator connected to each node between the current sources and the capacitors.

[0007] An integrating circuit can be used to supply gm*V CS (Current sensing voltage) The first current source and used to supply gm*V current. REF The second current source of the (reference voltage) current. The integral calculated value is divided into gm*V CS Current and capacitor, the first integral value in parabolic form and through gm*V REF The current and capacitor, and the second integral value in the form of a specific slope. When the magnitudes of the first and second integral values ​​are equal, the current control switch of the integrating circuit can be disconnected. Because V CS The current is affected by the internal CS terminal, so its current value changes.

[0008] However, in an integrator circuit, due to manufacturing issues or long-term use, the two current sources and the two capacitors may each have different values. This causes a change in the switching off timing, which in turn affects the accuracy of the system. Therefore, the integrator circuit may not have a constant operating time, making it impossible to stably perform average current control.

[0009] Generally, a fuse circuit can be added to the integration circuit to compensate for accuracy. The fuse circuit can refer to a first fuse circuit for compensating for a difference between gm values of the first current source and the second current source and a second fuse circuit for compensating for a difference between two capacitor values. The first fuse circuit can connect an additional current source in parallel with an existing current source, and the second fuse circuit can connect an additional capacitor in parallel with an existing capacitor. There can be at least three to four additional current sources or capacitors.

[0010] However, since the fuse circuit is also configured in the integration circuit as described above, the size of the integration circuit can not be reduced, and the size of the device can not be reduced.

[0011] Since the alternative integration circuit can be provided with two current sources and two capacitors, a difference in current source values or a difference in capacitor values can occur, and thus, the integration circuit can not have a constant operation time. In addition, a fuse circuit can also be configured in order to compensate for the difference. Thus, the configuration of the integration circuit can not be simplified, and the chip size can not be minimized. SUMMARY

[0012] The summary is provided to introduce a series of concepts in a simplified form that are further described below in the detailed description. This summary is neither intended nor constituted to identify key or essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter.

[0013] In a general aspect, an integration circuit includes a current source, a capacitor connected in series with the current source, a voltage source bias connected in series with the capacitor, a switch configured to connect a first node between the current source and the capacitor and a second node between the capacitor and the voltage source bias, and a switch control logic unit configured to control on / off operation of the switch, wherein an integration operation is performed by the current source and the capacitor.

[0014] The switch control logic unit can include an inverter buffer and an AND gate, and the switch control logic unit is configured to be in a non-operation state when an output of the AND gate is at a high level.

[0015] The current source can be configured to supply a current gm*(V REF between the reference voltage V CS and the current sensing voltage V REF -V CS ) value.

[0016] The voltage source bias can be configured to maintain a constant value of the second node.

[0017] An integration value calculated from the integration operation can have a difference with respect to when the reference voltage V REF and the current sensing voltage VCS A semi-circular shape that is symmetrical in time when they are equal.

[0018] The circuit may also include a comparator configured to alternately output an open signal and an on signal to the switch when the integral value calculated by the integral is equal to the voltage source bias.

[0019] The switching time can remain constant when the transfer conductance (gm) of the current source changes or when the size of the capacitor changes.

[0020] The operating time of the integrator circuit can remain constant when the conductance value gm of the current source or the size of the capacitor changes.

[0021] In general, the control methods for the integrator circuit include: supplying a current source based on a reference voltage V. REF With current sensing voltage V CS The difference in current between; integration calculation is performed by a current source and a capacitor connected in series with the current source; and when the integral value calculated by integration is equal to the bias of the voltage source, the switch is opened and closed, wherein the current sensing voltage V CS The voltage source bias remains constant as the predetermined time increases.

[0022] The increase and decrease of the integral value can be related to the reference voltage V. REF and current sensing voltage V CS The time intervals are equal and the same for both.

[0023] When the conductance value gm of the current source changes, the time for the switch to be turned on can remain constant.

[0024] When the size of the capacitor changes, the time the switch is turned on can remain constant.

[0025] The operating time of the integrator circuit can remain constant when the conductance gm of the current source changes or the size of the capacitor changes.

[0026] In a general sense, the switch controller includes: an integrator circuit comprising a current source, a capacitor connected in series with the current source, a voltage source bias connected in series with the capacitor, a switch configured to connect a first node between the current source and the capacitor and a second node between the capacitor and the voltage source bias, and a switch control logic unit configured to control the on / off operation of the switch; a comparator configured to compare a first integral value of the first node with a second integral value of the second node based on the integral calculation of the integrator circuit, and output an off signal SW_OFF to the switch control logic unit; an off-time controller configured to count the off-time based on the output of the comparator; and a switch driver configured to control the operation of the switch based on the outputs of the comparator and the off-time controller.

[0027] The integrator circuit can be configured to operate based on the output signal of the disconnection time controller.

[0028] The disconnection time controller can be configured to output a logic signal with a predetermined level to the set (SET) terminal of the switch driver after counting a predetermined time based on the output signal of the comparator.

[0029] In general, the integrating circuit includes: a single current source; a voltage source bias; a single capacitor connected in series with the single current source and configured to perform integration operation together with the single current source; and a switch configured to connect a first node between the current source and the capacitor to a second node between the capacitor and the voltage source bias.

[0030] The circuit may also include a switch control logic unit configured to control the on / off operation of the switch.

[0031] The circuit may also include a comparator configured to compare a first integral value of the first node with a second integral value of the second node based on an integral calculation of the integrator circuit, and to output a disconnect signal SW_OFF to the switch control logic unit.

[0032] Other features and aspects will become apparent from the following detailed description, drawings and claims. Attached Figure Description

[0033] Figure 1 Examples of integrating circuits according to one or more embodiments are shown.

[0034] Figure 2A The reference voltage V is shown according to one or more embodiments. REF With current sensing voltage V CS An example of the operating curves of an integrator circuit relating the relationship between the two circuits.

[0035] Figure 2B An example of an operating curve diagram of an integrating circuit showing a first integral value and a second integral value according to one or more embodiments is shown.

[0036] Figure 2C An example of an operating curve diagram of an integrator circuit indicating the operating state of a switch according to one or more embodiments is shown.

[0037] Figure 3A , Figure 3B as well as Figure 3C This is an example of a graph showing the switching operation state when the gm value of the current source provided in the integrating circuit changes, according to one or more embodiments.

[0038] Figure 4A , Figure 4B , Figure 4C , Figure 5A , Figure 5B as well as Figure 5C This is an example of a related technique that shows a graph illustrating the operating states when the values ​​of the first and second current sources are changed in a typical existing integrator circuit.

[0039] Figure 6A , Figure 6B as well as Figure 6C This is an example of a graph showing the switching operation state when the size of the capacitor disposed in the integrating circuit changes, according to one or more embodiments.

[0040] Figure 7A , Figure 7B , Figure 7C , Figure 8A , Figure 8B as well as Figure 8C This is an example of a related technique that shows the operating states when the values ​​of the first and second capacitors are changed in a typical integrating circuit.

[0041] Figure 9B and as related technologies Figure 9A An example comparing the layout of an example integrator circuit device with that of a typical integrator circuit device is shown.

[0042] Figure 10 An example circuit diagram of a converter with an integrator circuit according to one or more embodiments is shown.

[0043] Throughout the accompanying drawings and detailed description, unless otherwise described or provided, the same reference numerals will be understood to denote the same elements, features, and structures. The drawings may not be drawn to scale, and for clarity, illustration, and convenience, the relative dimensions, scale, and depiction of elements in the drawings may be exaggerated. Detailed Implementation

[0044] The following detailed description is provided to aid the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will become apparent upon understanding the disclosure of this application. For example, the sequences of operations described herein are merely examples, and are not limited to those set forth herein, except for those that must occur in a specific order, but may be modified as will become apparent upon understanding the disclosure of this application. Furthermore, for clarity and brevity, descriptions of features known in the art may be omitted.

[0045] The terminology used herein is for the purpose of describing various examples only and is not intended to limit the scope of this disclosure. The articles “a,” “an,” and “the” are also intended to include plural forms unless the context clearly indicates otherwise. The terms “comprising,” “including,” and “having” specify the presence of the stated feature, quantity, operation, component, element, and / or combination thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0046] Throughout the specification, when an element such as a layer, region, or substrate is described as "on another element," "connected to," or "coupled to" another element, it may be directly on, connected to, or coupled to the other element, or one or more other elements may be present in between. In contrast, when an element is described as "directly on another element," "directly connected to," or "directly coupled to" another element, there may be no other elements in between.

[0047] As used herein, the term “and / or” includes any one of the associated listed items and any combination of any two or more.

[0048] Although terms such as “first,” “second,” and “third” may be used herein to describe various components, parts, regions, layers, or sections, these components, parts, regions, layers, or sections are not limited by these terms. Rather, these terms are used only to distinguish one component, part, region, layer, or section from another. Therefore, without departing from the teachings of the examples described herein, the first component, part, region, layer, or section mentioned in the examples may also be referred to as the second component, part, region, layer, or section.

[0049] The terms “comprising,” “including,” and “having” specify the presence of the stated feature, quantity, operation, component, element, and / or combination thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0050] For ease of description, spatially relative terms such as “above,” “upper,” “lower,” and “below” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, such spatially relative terms are also intended to cover different orientations of the device in use or operation. For example, if the device in the drawings is flipped, an element described as “above” or “upper” relative to another element will be “below” or “lower” relative to that element. Thus, depending on the spatial orientation of the device, the term “above” encompasses both upper and lower orientations. The device may also be oriented in other ways (e.g., rotated 90 degrees or otherwise), and the spatially relative terms used herein should be interpreted accordingly.

[0051] As used herein, expressions such as “part” or “section” can include means in which the corresponding component may include a particular function, software that may include a particular function, or a combination of means and software that may include a particular function, but are not necessarily limited to the functions described only to aid in a more comprehensive understanding of this disclosure. Those skilled in the art will be able to make various modifications and variations based on this description.

[0052] Unless otherwise defined, all terms used herein, including technical and scientific terms, shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains, having understood the disclosure of this application. Terms, such as those defined in commonly used dictionaries, shall be interpreted as having the meaning consistent with their meaning in the context of the relevant technology and the disclosure of this application, and shall not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0053] Furthermore, all electrical signals used in this disclosure are illustrative. In these examples, if the circuit of this example also includes an inverter, the signs of all electrical signals described herein may be reversed. Therefore, the scope of this disclosure is not limited to the direction of the signals.

[0054] Therefore, the spirit of this disclosure should not be limited to the described examples, and all of the appended claims and their equivalents or derivatives fall within the scope of this disclosure.

[0055] The present disclosure will be described in more detail below with reference to the examples shown in the accompanying drawings. The present disclosure provides an integrating circuit that can have a reduced size compared to existing integrating circuits, while still performing normal integrating circuit operation. Reference will be made to... Figure 1 Describe the integrator circuit.

[0056] Figure 1 Examples of an integrator circuit 100 according to one or more embodiments are shown.

[0057] Reference Figure 1 The integrator circuit 100 in the example may include a supply based on a reference voltage V. REF With current sensing voltage V CS The difference in current gm*(V) between them REF -V CS The system includes a current source 110, a capacitor 120(C) connected in series with the current source 110, and a voltage source bias 130 as a voltage source. One end of the voltage source bias 130 is grounded. Here, with respect to examples or embodiments, the term "may" is used to mean that at least one example or embodiment includes or implements such a feature, but all examples and embodiments are not limited thereto.

[0058] In addition, refer to Figure 1 The integrator circuit 100 may also include a switch 150 connecting node A between the current source 110 and the capacitor 120 and node B between the capacitor 120 and the voltage source bias 130, and a switch control logic unit 101 for controlling the on / off operation of the switch 150.

[0059] The switch control logic unit 101 may include an inverting buffer 103 and an AND gate 105 as a logic device. In this example, the inverting buffer 103 and the AND gate 105 are configured as an integrating circuit 100. However, the input signal applied to the inverting buffer 103 and the AND gate 105 may be received from another circuit that constitutes the integrating circuit.

[0060] As shown in the following reference Figure 10 For example, if the switch control circuit 260 includes an integrator circuit, the input signal applied to the inverting buffer 103 and the AND gate 105 can be a control signal for the switch driver 262, whose control current controls the on-off operation of the switch 240. The switch driver 262 outputs the control signal by performing logical operations on the output of the comparator 140 and the output of the off-time controller 261.

[0061] According to the example, the driving of the integrator circuit 100 can be determined based on the level state of the output node C of the AND gate 105. In other words, when node C of the AND gate 105 is high, the integrator circuit 100 can remain in a non-operating state for a predetermined time, while when node C of the AND gate 105 is low, the integrator circuit 100 can operate for a predetermined time. The level changes of node C made by the switch control logic unit 101 are shown in Table 1 below.

[0062] Table 1:

[0063] SW OFF Start Node C Low Low Low Low High Low High Low High High High Low

[0064] As described above, in this example, the integrator circuit 100 may include a current source 110, a capacitor 120, a voltage source bias 130, and a switch control logic unit 101. The example integrator circuit 100 differs from a typical integrator circuit because it may include only one current source 110 and one capacitor 120. Furthermore, the example integrator circuit 100 differs from a typical integrator circuit in that a fuse is not required in the example integrator circuit 100. In a typical integrator circuit, a fuse is provided to compensate for defects caused by the difference between the values ​​of the current source and the capacitor. Note that a typical integrator circuit includes two current sources and two capacitors, while the example integrator circuit 100 may include only one current source 110 and one capacitor 120.

[0065] like Figure 1 As shown, comparator 140 can be connected to integrator 100. The connection between integrator 100 and comparator 140 can have a configuration in which node A is connected to the inverting terminal (-) and node B is connected to the non-inverting terminal (+), and an off signal SW_OFF, which is the output of comparator 140, is applied to AND gate 105.

[0066] Next, the operation of the example integrator circuit configured as described above will be described. This will be done by comparing the operation graphs of the example integrator circuit and a typical integrator circuit, so that the differences between the example integrator circuit and a typical integrator circuit can be identified.

[0067] Figures 2A to 2C An example of the operating curves for an example integrator circuit is shown. Specifically, Figure 2A The reference voltage V is shown. REF With current sensing voltage V CS The relationship between them Figure 2B The first integral value and the second integral value are shown, as well as Figure 2C An example of the switch operation state is shown.

[0068] Reference Figure 2A Reference voltage V REF It can maintain a constant value, and the current sensing voltage V CS It can increase at a predetermined slope within a predetermined time period (0~t1, t2~t3, t4~t5, ...). When performing integration calculations under this state, the "first integral value" at node A can be obtained through the relation "gm*(V REF -V CS —This is the supply current for current source 110 and capacitor 120—displayed as a symmetrical semicircle, such as Figure 2B As shown in the image.

[0069] That is, refer toFigure 2B Regarding the reference voltage V REF and current sensing voltage V CS The time "a" when they are equal is when the reference voltage V REF Greater than the current sensing voltage V CS When the first integral value increases, and in contrast, when the reference voltage V... REF Less than the current sensing voltage V CS As time progresses, the first integral value decreases, therefore the first integral value is symmetric about time "a".

[0070] Node B of the integrator circuit 100 can remain constant based on the bias voltage. In this example, the bias voltage will be referred to as the "second integral value".

[0071] Figure 2C The on and off states of switch 150 are shown. (Refer to the diagram.) Figure 2B and Figure 2C Switch 150 is opened at time a' when the first integral value and the second integral value are equal, and remains at a low level for a predetermined time (0 to t1, t2 to t3). This state refers to the state when node C in Table 1 is low and the time period during which the integrator circuit is actually operated (0 to t1, t2 to t3).

[0072] In the example, the switch can be turned on at time a” when the first and second integral values ​​are equal again to stop the operation of the integrator circuit. This state is referred to as the time when node C is high in Table 1, and corresponds to the time period between t1 and t2.

[0073] The switch can be turned off again at time t2 to start the integrating circuit, and can remain open until time t3.

[0074] Such time periods can be repeatedly generated, during which integral calculations of the integrator circuit are performed (0 to t1, t2 to t3) and integral calculations of the integrator circuit are not performed (t1 to t2).

[0075] When performing such integral calculations, the gm value or capacitor value of the example integrator circuit can also be changed. However, the on-time of the switch in the example integrator circuit can remain unchanged. This will be referred to... Figures 3A to 3C and Figures 4A to 4C Describe it.

[0076] Figures 3A to 3C This is a graph showing the switching operation states as the value of gm of the current source set in the example integrator circuit changes. Since the example integrator circuit may only have one current source, it may not be possible to compare it with other gm values, but the gm value may change due to process dispersion or similar processes.

[0077] like Figure 3A As shown, the reference voltage V REF It can maintain a constant value, and the current sensing voltage V CS It can increase at a predetermined slope within a predetermined time period (0 to t1, t2 to t3, t4 to t5, ...).

[0078] Figure 3B The state of change based on the integral value calculated from the integral is shown. When performing the integral calculation, the bias, which is the second integral value, can remain constant. On the other hand, when the value of gm changes due to the process dispersion of gm, the supply current "gm*(V)" as the current source... REF -V CS The value of “)*C”—which is the first integral value—is changed.

[0079] However, even if the gm value is greater than the preset reference value gm ref (gm>gm ref (), or less than the preset reference value gm ref (gm <gm ref The gm value can also be related to the reference voltage V. REF and current sensing voltage V CS The symmetrical change of "a" over the same period of time makes the increase and decrease of the integral value appear to be the same.

[0080] In other words, when the gm value is greater than the preset reference value gm ref (gm>gm ref (or less than the preset reference value gm) ref (gm <gm ref In both cases, when the reference voltage V REF Greater than the current sensing voltage V CS At that time, the first integral value will increase, and with the reference voltage V REF and current sensing voltage V CS Over the same time interval "a", when the reference voltage V... REF It becomes less than the current sensing voltage V CS When this happens, the first integral value decreases. Therefore, the width of the first integral value can remain unchanged and can fluctuate only in the vertical direction (the dotted line portion), such as... Figure 3B As shown in the image.

[0081] Therefore, regardless of how the gm value changes, the on-state operation time (t1, t3) of switch 150 can remain unchanged. Since the on-state (t1, t3) time is constant, the off-state holding time (0 to t1, t2 to t3) can also be constant. Therefore, the operating time of the integrating circuit can be constant.

[0082] Therefore, since the exemplary integrating circuit can have a simple configuration compared to a typical integrating circuit, the accuracy of the system may not change, and an additional fuse circuit may not be necessary.

[0083] In contrast, the operation of a typical integrating circuit will be described with reference to Figures 4A to 4C and Figures 5A to 5C illustrated.

[0084] In a typical integrating circuit, two current sources are configured, and Figures 4A to 4C it is shown that the gm1 value of the first current source is greater than the gm2 value of the second current source (gm1 > gm2) or less than the gm2 value of the second current source (gm1 < gm2). Figures 5A to 5C It is shown that the gm2 value of the second current source is greater than the gm1 value of the first current source (gm2 > gm1) or less than the gm1 value of the first current source (gm2 < gm1).

[0085] In Figures 4A to 4C when the gm1 value of the first current source is changed to be greater than gm2 of the second current source (gm1 > gm2), the first integration value “b” becomes shorter. Thus, the time when switch 150 is turned on is faster than the normal time t1 and is turned on at time t1'. Similarly, when the gm1 value of the first current source is less than gm2 of the second current source (gm1 < gm2), the first integration value “b'” becomes longer. Thus, the time when switch 150 is turned on becomes slower than the normal time t3, and switch 150 is turned on at time t3'. The change in the turn-on time means that the operation time of the integrating circuit changes according to the difference between the gm1 value and the gm2 value.

[0086] When Figures 5A to 5C the gm2 value of the second current source changes, the same method can be applied. If the gm2 value of the second current source is changed to be greater than gm1 of the first current source, the slope “c” of the second integration value can be further inclined. Thus, the time when switch 150 is turned on is faster than the normal time t1 and is turned on at time t1'. On the other hand, if the gm2 value of the second current source is less than gm1 of the first current source, the slope “c'” of the second integration value will be flatter, such that the time when switch 150 is turned on is slower than the normal time t3 and is thus turned on at time t3'.

[0087] As described above, in a typical integrating circuit, the turn-on time of switch 150 changes from t1 or t3 of the normal time to t1' or t3' according to the gm value. Therefore, a fuse circuit should be added to the integrating circuit to compensate for the difference.

[0088] In addition to the gm value, the exemplary integrating circuit also affects the accuracy of the system by changing the capacitor size.

[0089] Figures 6A to 6C It is a graph showing the switching operation state when the size of the capacitor in the exemplary integrating circuit is changed. As discussed above, the exemplary integrating circuit may include only a single capacitor. However, the size of the capacitor may vary due to process dispersion or similar processes. When the size of the capacitor is changed, the value of the capacitor value may also change.

[0090] As Figure 6A shown, the reference voltage V of the exemplary integrating circuit REF can remain at a constant value, and the current sensing voltage V CS can increase at a predetermined slope within a predetermined time (0 to t1, t2 to t3, t4 to t5, etc.).

[0091] Referring to Figure 6B , the state of change of the integral value according to the integral calculation is shown. When the integral calculation is performed, the bias as the second integral value can remain at a constant value. Alternatively, when the capacitor value changes due to, for example, process dispersion, the supply current "gm*(V REF -V CS )*C" of the current source as the first integral value can be changed.

[0092] However, even if the value of the capacitor is greater than or less than the preset reference value Cref, the increase and decrease of the value of the first integral value of the integral calculation may seem the same because the change is symmetric about the time "a" when the reference voltage V REF and the current sensing voltage V CS are equal.

[0093] In the example, in two examples where the value of the capacitor is less than the preset reference value Cref (C < Cref) or greater than the preset reference value Cref (C > Cref), with respect to the time "a", when the reference voltage V REF is greater than the current sensing voltage V CS the first integral value increases, and when the reference voltage V REF is less than the current sensing voltage V CS the first integral value decreases. Therefore, the width of the first integral value may not change, but may only fluctuate in the vertical direction (dashed part), as Figure 6B shown.

[0094] Therefore, regardless of how the value of the capacitor changes, the on - time (t1, t3) of the switch 150 may not change. When the on - time (t1 and t3) is constant, the holding time of the off state (0 to t1, t2 to t3) can be constant. That is, the operation time of the integrating circuit can be provided constantly.

[0095] In contrast, reference will be made to Figures 7A to 7C [ andFigures 8A to 8C Describe the operation in a typical integrating circuit.

[0096] In a typical integrating circuit, two capacitors C1 and C2 can be connected to different nodes respectively, and when there is a dimensional difference between the size of the capacitor connected to the first node and the size of the capacitor connected to the second node, the holding time of the switch 150 being turned on can be different between the two capacitors. Specifically, the operation time of the integrating circuit depends on the dimensional difference between capacitors C1 and C2.

[0097] Figures 7A to 7C Examples are shown where the size of capacitor C1 connected to the first node is smaller than the size of capacitor C2 connected to the second node (C1 < C2) or larger than the size of capacitor C2 connected to the second node (C1 > C2). When the size of the first capacitor C1 is smaller than the size of the second capacitor C2 (C1 < C2), the first integration value d becomes longer. Thus, the switch is turned on at a time t1' slower than the normal time t1. On the other hand, when the size of the first capacitor C1 is larger than the size of the second capacitor C2 (C1 > C2), the first integration value d' is shortened, and the time when the switch is turned on is faster than the normal time t3, so the switch is turned on at t3'.

[0098] Figures 8A to 8C Examples are shown where the size of the second capacitor C2 is smaller than the size of the first capacitor (C2 < C1) or larger than the size of the first capacitor C1 (C2 > C1). When the size of the second capacitor C2 is larger than the size of the first capacitor C1 (C2 > C1), the slope e of the second integration value can be gentler, so the switch 150 can be turned on at a time t1' slower than the normal time t1. On the other hand, if the size of the second capacitor C2 is smaller than the size of the first capacitor C1 (C2 < C1), the slope e' of the second integration value becomes steeper, such that the switch 150 is turned on at a time t3' faster than the normal time t3.

[0099] As described above, in a typical integrating circuit, the time when the switch 150 is turned on can change from the normal time t! or t3 to t1' or t3' according to the value of the capacitor. Therefore, even if the value of the capacitor changes, it may be necessary to add a fuse circuit to the typical integrating circuit.

[0100] In the above integrating circuit, when the gm value of the current source or the capacitor value changes, the time when the switch 150 is turned on may change. Therefore, it may be necessary to add a fuse circuit to compensate for the changed value so that the configuration of the integrating circuit may not be simplified.

[0101] On the other hand, the example integrator circuit may not include a fuse circuit because the time when switch 150 is turned on can be kept constant even if the value of gm or the value of the capacitor changes, and therefore the example integrator circuit is simplified and its size can be reduced.

[0102] Furthermore, although the example integrator circuit has been simplified as described above, the on and off periods of switch 150 remain constant even if the gm value or the capacitor value changes, so that there is no significant difference in function from a typical integrator circuit.

[0103] Figure 9A and Figure 9B An example comparing the layout of a typical integrator circuit and an example integrator circuit is shown. Figure 9A and Figure 9B The layout includes comparators.

[0104] Figure 9A A typical integrator circuit shown may include: two current sources gm, two capacitors C, a comparator comp, two switches SW, fuse circuits gm-fuse and C-fuse for each current source gm and capacitor C to compensate for problems caused by changes in the values ​​of the current sources gm and capacitors C, logic for controlling the fuse circuits, etc.

[0105] Figure 9B An example integrator circuit is shown, which may consist of only a current source gm, a capacitor C, a comparator comp, and a switch SW. Compared to a typical integrator circuit, the example integrator circuit may omit the fuse circuit, except for the reduction in the number of current sources and capacitors.

[0106] Based on the simulation results, the size of the example integrator circuit is about 1 / 6 of that of a typical integrator circuit.

[0107] The example integrating circuit can be applied to a variety of devices. As a non-limiting example, the example integrating circuit can be applied to a variety of switching control devices, LED backlight driving devices, and display devices.

[0108] Figure 10 An example circuit diagram of a converter including an integrator circuit according to one or more embodiments is shown.

[0109] Reference Figure 10 In a non-limiting example, the example integrator circuit can be configured in converter 200. Specifically, Figure 10 The integrator 100 can correspond to the integrator circuit of the example described above. Therefore, the integrator 100 may include a current source 110, a capacitor C 120, a voltage source bias 130, a switch 150, and a switch control logic unit 101.

[0110] The converter 200 may be configured with an integrator 100, a comparator 140, a disconnection time controller 261 that counts disconnection times based on the output of the comparator 140, and a switch driver 262 that may include an SR latch, the switch driver controlling the operation of the current control switch 240 based on the outputs of the comparator 140 and the disconnection time controller 261.

[0111] The converter 200 may further include a load 210 and an inductor 220 connected in series with the input power VIN. The inductor stores or releases energy supplied through the input power VIN according to the operation of the current-controlled switch 240. The load 210 and inductor 220 may be connected with a return diode 230 to form a current path (loop) that supplies corresponding energy to the load 210 when energy is released from the inductor 220. The converter 200 may also include a current-measuring resistor 250 connected between one end of the current-controlled switch 240 and a reference potential to measure the current flowing through the load 210.

[0112] In a converter 200 with such an example integrating circuit, integrator 100 can perform integration calculations based on a control signal (i.e., a start signal) from a switch driver 262 that turns on the gate terminal of current control switch 240. Since current control switch 240 can receive a control operation from disconnect time controller 261, this control signal can be the output signal of disconnect time controller 261.

[0113] Based on the example integrator circuit and control method described above, average current control can be performed more accurately than typical integrator circuits by providing an integrator circuit with a constant operating time.

[0114] The chip size can be minimized because it can be implemented using only a current source and a capacitor. Since the number of current sources and capacitors can be reduced, and the example integrator circuit may not require the fuse circuit used in typical integrator circuits, the chip size can be significantly minimized. Based on simulation results, the chip size can be minimized by approximately 1 / 6 compared to a typical integrator circuit.

[0115] Furthermore, such a minimized chip size can increase the design efficiency of various devices implementing the example integration circuit. As a non-limiting example, the device may be a switch control circuit, a converter with a switch control circuit, an LED backlight driver, a display device, and similar apparatus.

[0116] While this disclosure includes specific examples, it will be apparent upon understanding the disclosure of this application that various changes in form and detail may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein should be considered descriptive only and not for limiting purposes. The description of features or aspects in each example should be considered applicable to similar features or aspects in other examples. Suitable results may be achieved if the described techniques are performed in a different order, and / or if components in the described system, architecture, apparatus, or circuit are combined in different ways and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of this disclosure is not limited by the detailed description but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents should be construed as included in this disclosure.

Claims

1. An integrating circuit, comprising: Current source; A capacitor connected in series with the current source; A voltage source is biased and connected in series with the capacitor; A switch, configured to connect a first node between the current source and the capacitor and a second node between the capacitor and the voltage source bias; as well as A switch control logic unit, configured to control the on / off operation of the switch. The integration operation is performed by the current source and the capacitor. The switch control logic unit includes an inverting buffer and an AND gate.

2. The integrating circuit according to claim 1, in, The switch control logic unit is configured to be in a non-operating state when the output of the AND gate is high.

3. The integrating circuit according to claim 1, in, The current source is configured to supply the first node with a current based on a reference voltage (V). REF ) and current sensing voltage (V CS The difference in current value between the reference voltage (V) and the reference voltage (V). REF ) and the current sensing voltage (V CS The product of the difference between the two and the conductance (gm) of the current source.

4. The integrating circuit according to claim 1, in, The voltage source bias is configured to maintain a constant value for the second node.

5. The integrating circuit according to claim 3, in, The integral value calculated from the integration operation has a semi-circular shape, the semi-circular shape being relative to the reference voltage (V). REF ) and the current sensing voltage (V CS Time symmetry occurs when they are equal.

6. The integrating circuit of claim 4 further includes a comparator configured to alternately output an open signal and an open signal to the switch when the integrated value calculated by integration is equal to the voltage source bias.

7. The integrating circuit according to claim 1, in, The switching time remains constant when the conductance (gm) of the current source changes or when the size of the capacitor changes.

8. The integrating circuit according to claim 1, in, The operating time of the integrator circuit remains constant when the conductance (gm) of the current source or the size of the capacitor changes.

9. A control method for an integrating circuit, the method comprising: Powered by a current source based on a reference voltage (V) REF ) and current sensing voltage (V CS The difference in current between ) Integral calculations are performed using the current source and the capacitor connected in series with the current source; as well as When the integral value calculated by the integral is equal to the voltage source bias, the switch is opened and closed. Wherein, the current sensing voltage (V) CS The voltage source bias remains constant as the predetermined time increases.

10. The method according to claim 9, in, The increase and decrease of the integral value are the same with respect to the following time: the reference voltage (V REF ) and the current sensing voltage (V CS They are equal at that time.

11. The method according to claim 9, in, When the conductance (gm) of the current source changes, the following time remains constant, at which the switch is turned on.

12. The method according to claim 9, in, When the size of the capacitor changes, the following time remains constant, at which the switch is turned on.

13. The method according to claim 9, in, The operating time of the integrator circuit remains constant when the conductance (gm) of the current source changes or the size of the capacitor changes.

14. A switch controller, comprising: An integrating circuit, the integrating circuit including a current source, a capacitor connected in series with the current source, a voltage source bias connected in series with the capacitor, a switch configured to connect a first node between the current source and the capacitor and a second node between the capacitor and the voltage source bias, and a switch control logic unit configured to control the on / off operation of the switch. A comparator configured to compare a first integral value of the first node with a second integral value of the second node based on the integral calculation of the integrator circuit, and to output a disconnect signal (SW_OFF) to the switch control logic unit; A disconnection time controller is configured to count disconnection times based on the output of the comparator; as well as A switch driver configured to control the operation of the switch based on the outputs of the disconnection time controller and the comparator. The switch control logic unit includes an inverting buffer and an AND gate.

15. The switch controller according to claim 14, in, The integrator circuit is configured to operate based on the output signal of the disconnection time controller.

16. The switch controller according to claim 14, in, The disconnection time controller is configured to output a logic signal with a predetermined level to the setting terminal of the switch driver after counting a predetermined time based on the output signal of the comparator.

17. An integrating circuit, comprising: Single current source; Voltage source bias; A single capacitor, which is connected in series with the single current source and configured to perform an integration operation together with the single current source; A switch configured to connect a first node between the single current source and the single capacitor and a second node between the single capacitor and the voltage source bias, and A switch control logic unit, configured to control the on / off operation of the switch. The switch control logic unit includes an inverting buffer and an AND gate.

18. The integrator circuit of claim 17, further comprising a comparator configured to compare a first integral value of the first node with a second integral value of the second node based on an integral calculation of the integrator circuit, and to output a disconnect signal SW_OFF to the switch control logic unit.

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