Voltage stabilizing circuit and electronic device

Abstract

This application relates to the fields of electronics and semiconductor devices, and provides a voltage regulator circuit and an electronic device. The voltage regulator circuit is formed on a semiconductor substrate and includes a pre-stage voltage regulator module, a low-pass filter module, and a post-stage voltage regulator module connected in series. The low-pass filter module includes a resistor and a capacitor electrically connected on the semiconductor substrate. Thus, the voltage is stabilized at the required level by the pre-stage voltage regulator module, and then the noise introduced by the pre-stage voltage regulator module is filtered out by the low-pass filter module, thereby enabling the output of a stable voltage with low noise from the post-stage voltage regulator module. Although the voltage regulator circuit of this application increases the device area by adding a low-pass filter module and a post-stage voltage regulator module, compared with conventional noise reduction methods, this application achieves higher noise reduction efficiency with the same increase in area.

Description

Technical Field

[0001] This application relates to the fields of electronic technology and semiconductor devices, and more particularly to a voltage regulator circuit and an electronic device. Background Technology

[0002] The noise in a voltage regulator circuit mainly originates from the power supply providing the reference voltage (e.g., a bandgap reference source) and the error amplifier. This noise primarily consists of low-frequency flicker noise (0.1–10 Hz) and thermal noise (10 Hz to several hundred kHz). The basic value of the 0.1–10 Hz noise is approximately tens of μV / V. (p-p) The basic value of noise in the range of 10Hz to several hundred kHz is approximately several hundred μV / V. (p-p) In applications where noise levels are critical, the presence of this noise poses a significant challenge for technicians.

[0003] Traditional solutions mainly rely on increasing the area of ​​internal components to reduce flicker noise and increasing the transconductance of internal components to reduce the above two types of noise.

[0004] This section is intended to provide background or context for the embodiments of this application set forth in the claims. The description herein is not an admission that it is prior art simply because it is included in this section. Summary of the Invention

[0005] The inventors discovered that increasing the area of ​​internal components or improving the transconductance of internal components not only increases the overall cost of the device, but also leads to a significant increase in power consumption. Furthermore, for applications with extremely high noise requirements, the area of ​​internal components needs to be increased by several times or even hundreds of times in order to reduce the noise below the required threshold. However, this not only increases the cost, but also makes the device larger and unable to meet other requirements such as size.

[0006] To address at least one of the above-mentioned problems or other similar problems, embodiments of this application provide a voltage regulator circuit and an electronic device.

[0007] According to a first aspect of the present application, a voltage regulator circuit is provided, the voltage regulator circuit being formed on a semiconductor substrate, the voltage regulator circuit including a front-end voltage regulator module, a low-pass filter module and a back-end voltage regulator module connected in series, the low-pass filter module including a resistor and a capacitor electrically connected on the semiconductor substrate.

[0008] In at least one embodiment, the resistor includes an NMOS transistor and a PMOS transistor whose source and drain are respectively connected, and a voltage source electrically connected to the gate of the NMOS transistor and the PMOS transistor respectively.

[0009] In at least one embodiment, the gate voltages applied to the NMOS and PMOS transistors vary with temperature, such that the product of the resistance value of the resistor and the capacitance value of the capacitor changes by 0 with respect to temperature.

[0010] In at least one embodiment, when the temperature exceeds a predetermined threshold, the capacitance of the capacitor decreases as the temperature rises, and the resistance of the resistor increases as the temperature rises.

[0011] In at least one embodiment, when the resistance value of the resistor and the capacitance value of the capacitor are expressed in scientific notation, the resistance value of the resistor is on the order of 10¹⁹ or more of the capacitance value of the capacitor.

[0012] In at least one embodiment, the post-stage voltage regulator module includes an LDO linear regulator circuit, the LDO linear regulator circuit includes an error amplifier, and the error amplifier is a chop architecture or an auto-zero architecture.

[0013] In at least one embodiment, the reference voltage of the pre-stage voltage regulator module is provided by a bandgap reference source, and the reference voltage of the post-stage voltage regulator module is the output voltage of the low-pass filter module.

[0014] According to a second aspect of the embodiments of this application, an electronic device is provided, the electronic device including the voltage regulator circuit described in the embodiments of the first aspect.

[0015] One of the beneficial effects of this application embodiment is that the voltage is stabilized at the required level by the pre-stage voltage regulator module, and then the noise brought by the pre-stage voltage regulator module is filtered out by the low-pass filter module, so that a stable voltage with low noise can be output from the post-stage voltage regulator module. Although the voltage regulator circuit of this application embodiment increases the area of ​​the device by adding the low-pass filter module and the post-stage voltage regulator module, compared with the traditional noise reduction method, the noise reduction efficiency of this application is higher when the area is increased by the same. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic block diagram of a voltage regulator circuit according to an embodiment of this application.

[0018] Figure 2 This is a circuit diagram of the voltage regulator circuit according to an embodiment of this application.

[0019] Figure 3 This is a schematic diagram of one implementation of the resistor in the low-pass filter module of this application embodiment.

[0020] Figure 4 Is with Figure 3 The diagram shows the change in current of the voltage source corresponding to the NMOS transistor as a function of temperature.

[0021] Figure 5 Is with Figure 3 The diagram shows the change in current of the voltage source corresponding to the PMOS transistor as a function of temperature. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments and their descriptions are used to explain this application, but are not intended to limit this application.

[0023] In the embodiments of this application, the terms "first," "second," "upper," "lower," etc., are used to distinguish different elements by their names, but do not indicate the spatial arrangement or temporal order of these elements, and these elements should not be limited by these terms. The term "and / or" includes any one or more of the terms listed in connection with the application and all combinations thereof. The terms "comprising," "including," "having," etc., refer to the presence of the stated features, elements, components, or assemblies, but do not exclude the presence or addition of one or more other features, elements, components, or assemblies.

[0024] In the embodiments of this application, the singular forms "a," "the," etc., including the plural forms, should be broadly understood as "a kind" or "a class" rather than limited to the meaning of "an." Furthermore, the term "the" should be understood to include both the singular and plural forms, unless the context explicitly indicates otherwise. Additionally, the term "according to" should be understood as "at least partially based on…," and the term "based on" should be understood as "at least partially based on…," unless the context explicitly indicates otherwise.

[0025] First aspect of the embodiments

[0026] The first aspect of this application provides a voltage regulator circuit. This voltage regulator circuit can be formed on a semiconductor substrate, and may be, for example, a voltage regulator chip or a portion thereof. This application does not limit the manufacturing process of the voltage regulator circuit; specific details can be found in related technologies. Figure 1 This is a schematic block diagram of a voltage regulator circuit according to an embodiment of this application. Figure 2 This is a circuit diagram of the voltage regulator circuit according to an embodiment of this application.

[0027] like Figure 1 As shown, the voltage regulator circuit 100 includes a pre-stage voltage regulator module 110, a low-pass filter module 120, and a post-stage voltage regulator module 130 connected in series. The pre-stage voltage regulator module 110 and the post-stage voltage regulator module 130 can be implemented using LDO linear regulator circuits, which will be described in detail later.

[0028] The low-pass filter module 120 can be, for example, an RC low-pass filter, or other types of low-pass filters, such as an LC low-pass filter. This application does not limit the specific type of low-pass filter used. The following description uses an RC low-pass filter as an example to illustrate the low-pass filter module 120. Those skilled in the art should understand that other types of low-pass filters can be used for equivalent substitutions, which will not be described in detail here.

[0029] like Figure 2 As shown, the low-pass filter module 120 includes a resistor 121 and a capacitor 122 electrically connected. The resistor 121 and capacitor 122 are, for example, resistive devices and capacitors formed on a semiconductor substrate. This application does not limit how the resistive devices and capacitors are formed on the semiconductor substrate; specific details can be found in related technologies.

[0030] Figure 3 This is a schematic diagram of one implementation of the resistor in the low-pass filter module of this application embodiment.

[0031] like Figure 3 As shown, resistor 121 may include an NMOS transistor 1211 and a PMOS transistor 1212 whose source and drain are respectively connected, and voltage sources 1213 and 1214 electrically connected to the gates of the NMOS transistor 1211 and the PMOS transistor 1212, respectively. Voltage sources 1213 and 1214 may be composed of constant current sources and resistors, for example, voltage source 1213 is composed of constant current source I1 and resistor R4 connected in series, and voltage source 1214 is composed of constant current source I2 and resistor R5, for example. Specific implementations of the voltage sources can be found in related technologies, and the embodiments of this application do not limit them.

[0032] In at least one embodiment, the gate voltages applied to the NMOS transistor 1211 and the PMOS transistor 1212 vary with temperature, such that the product of the resistance value of resistor 121 and the capacitance value of capacitor 122 changes by 0 with respect to temperature.

[0033] It should be noted that those skilled in the art should understand that, due to limitations such as process precision and measurement precision, the "change amount is 0" mentioned in the embodiments of this application means that the change amount is 0 within the error range, or that the change amount is 0 within the acceptable range, or that the change amount is below a predetermined threshold, such as 0 to 1.

[0034] Figure 4 Is with Figure 3 The diagram shows the change in current of the voltage source corresponding to the NMOS transistor as a function of temperature. Figure 5 Is with Figure 3 The diagram shows the change in current of the voltage source corresponding to the PMOS transistor as a function of temperature.

[0035] The following is combined with Figure 4 and Figure 5 The change in resistance value of resistor 121 in this application with respect to temperature will be explained.

[0036] In this example, if the resistance value of resistor 121 remains unchanged, the capacitance value of capacitor 122 is generally assumed to remain unchanged as well, unless otherwise specified. For example, if the capacitance value of capacitor 122 changes, a special explanation will be given.

[0037] like Figure 4 As shown, voltage source 1213 ( Figure 4 The current (not shown) is positive and decreases as the temperature rises. Consequently, the voltage applied to the gate of NMOS transistor 1211 also decreases with rising temperature. As the temperature rises, the turn-on voltage of the NMOS transistor decreases, and its on-resistance decreases accordingly. By decreasing the gate voltage of NMOS transistor 1211, its on-resistance can be increased. Adjusting the gate voltage allows the on-resistance of NMOS transistor 1211 to be maintained within a preset range, thus keeping the resistance value of resistor 121 constant even as the temperature rises. Similarly, the same applies when the temperature decreases. That is, as the temperature decreases, the turn-on voltage of the NMOS transistor increases, and its on-resistance increases accordingly. By increasing the gate voltage of NMOS transistor 1211, its on-resistance can be decreased. Adjusting the gate voltage allows the on-resistance of NMOS transistor 1211 to be maintained within a preset range, thus keeping the resistance value of resistor 121 constant even as the temperature decreases.

[0038] like Figure 5 As shown, voltage source 1214 ( Figure 5The current (not shown) is negative and increases with rising temperature. Consequently, the voltage applied to the gate of PMOS transistor 1212 also increases with temperature. As temperature rises, the turn-on voltage of the PMOS transistor decreases, and its on-resistance decreases accordingly. By increasing the gate voltage of PMOS transistor 1212, its on-resistance can be increased. Adjusting the gate voltage allows the on-resistance of PMOS transistor 1212 to be maintained within a preset range, thus keeping the resistance value of resistor 121 constant even as temperature rises. Similarly, the same applies when temperature decreases. That is, as temperature decreases, the turn-on voltage of PMOS transistor 1212 decreases, and its on-resistance increases accordingly. By decreasing the gate voltage of PMOS transistor 1212, its on-resistance can be decreased. Adjusting the gate voltage allows the on-resistance of PMOS transistor 1212 to be maintained within a preset range, thus keeping the resistance value of resistor 121 constant even as temperature decreases.

[0039] In this way, the resistor formed by bridging the PMOS and NMOS transistors maintains a constant resistance value regardless of temperature rise or fall. Furthermore, in this embodiment, the resistance value of resistor 121 can be set to any value according to actual needs; for example, the resistance value can be 10 GΩ. Therefore, a resistor with a large resistance value can be formed with a very small device area.

[0040] In at least one embodiment, when the temperature exceeds a predetermined threshold, the capacitance of capacitor 122 may decrease as the temperature rises. Therefore, the resistance of resistor 121 can be increased as the temperature rises, thus ensuring that the product of the resistance of resistor 121 and the capacitance of capacitor 122 changes by zero with respect to temperature. For example, capacitor 122 may leak current at high temperatures, causing its capacitance to decrease. In this case, the gate voltage applied to NMOS transistor 1211 and / or PMOS transistor 1212 can be adjusted to increase the on-resistance of NMOS transistor 1211 and / or PMOS transistor 1212, thereby increasing the resistance of resistor 121. Because the resistance of resistor 121 can change with temperature, such resistor 121 is sometimes referred to as a "variable resistor."

[0041] In at least one embodiment, when the resistance value of resistor 121 and the capacitance value of capacitor 122 are expressed in scientific notation, the order of magnitude of the resistance value of resistor 121 is 10 times the order of magnitude of the capacitance value of capacitor 122. 19 That's all. For example, the resistance of resistor 121 can be 1 GΩ, that is, 1 × 10⁻⁶. 9 Ω, the capacitance of capacitor 122 can be 100pF, that is, 1×10 -10F. Additionally, the resistance value of resistor 121 can be above 1 GΩ, and the capacitance value of capacitor 122 can be below 100 pF. This application embodiment does not impose any limitations on this, as long as the cutoff frequency of the low-pass filter module 120 is within the required range (predetermined range). Alternatively, the cutoff frequency of the low-pass filter module 120 can be made as small as possible, which can filter out most of the noise and provide a lower-noise reference voltage for the subsequent voltage regulator module 130.

[0042] In at least one embodiment, such as Figure 2 As shown, the post-stage voltage regulator module 130 may include an LDO linear regulator circuit, which includes an error amplifier A2, a transistor T2, and a resistor R3. The error amplifier A2 may be a chop architecture or an auto-zero architecture. This reduces the noise of the post-stage voltage regulator module 130, resulting in a lower noise output voltage. Additionally, as... Figure 2 As shown, the pre-stage voltage regulator module 110 may also include an LDO linear voltage regulator circuit, and its specific structure can be referred to in related technologies. This application embodiment does not limit this.

[0043] In addition, such as Figure 2 As shown, the pre-amplifier module 110 includes an error amplifier A1, a transistor T1, resistors R1 and R2. The output voltage of the pre-amplifier module 110 can be adjusted by regulating resistors R1 and R2. Additionally, the reference voltage of the pre-amplifier module 110 can be provided by a bandgap reference source 200. The implementation of the bandgap reference source 200 can refer to related technologies, and this application embodiment does not limit its implementation. The error amplifier A1 can adopt a conventional architecture, a chop architecture, or an auto-zero architecture; this application embodiment does not limit its implementation.

[0044] In addition, such as Figure 2 As shown, the reference voltage of the subsequent voltage regulator module 130 is the output voltage of the low-pass filter module 120. Therefore, even if the bandgap reference source 200 and the pre-stage voltage regulator module 110 introduce noise, the low-pass filter module 120 can filter out the noise as needed, and the noise of the signal input to the subsequent voltage regulator module 130 can meet the actual requirements.

[0045] In some embodiments, transistor T2 occupies a larger area than transistor T1 in the device. Since the output of the pre-stage voltage regulator module 110 only needs to provide a reference voltage to the subsequent circuit, the load-carrying capacity of transistor T1 can be relatively small, thus the area occupied by transistor T1 can be smaller; the output Vout of the subsequent voltage regulator module 130 needs to carry a load, therefore, transistor T2 occupies a larger area than transistor T1.

[0046] Additionally, it should be noted that Figure 2 The illustration uses an n-type transistor as an example, but this application does not limit this, and p-type transistors can also be used in the pre-stage voltage regulator module 110 and the post-stage voltage regulator module 130.

[0047] According to the voltage regulator circuit described in the first aspect of this application, the voltage is stabilized at the required level by the pre-stage voltage regulator module, and then the noise introduced by the pre-stage voltage regulator module is filtered out by the low-pass filter module, so that a stable voltage with low noise can be output from the post-stage voltage regulator module. Although the voltage regulator circuit of this application increases the area of ​​the device by adding the low-pass filter module and the post-stage voltage regulator module, it is more efficient in reducing noise than using conventional noise reduction methods, with the same increase in area.

[0048] Second aspect of the embodiments

[0049] The second aspect of this application provides an electronic device that includes the voltage regulator circuit described in the first aspect embodiment. Since the structure and features of the voltage regulator circuit have been described in detail in the first aspect embodiment, the details are incorporated herein by reference and are omitted here.

[0050] In addition, the electronic device may be a communication device that complies with the fifth generation mobile communication standard or may be included in the communication device. The electronic device may also include other electronic components. For details, please refer to the relevant technology. This application embodiment does not limit this.

[0051] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A voltage stabilizing circuit, characterized by comprising: The voltage stabilizing circuit is formed on a semiconductor substrate, and includes a front-stage voltage stabilizing module, a low-pass filter module and a rear-stage voltage stabilizing module connected in series, the low-pass filter module includes an electrically connected resistor and capacitor formed on the semiconductor substrate, The resistor includes an NMOS transistor and a PMOS transistor connected to the source and the drain respectively, and a voltage source electrically connected to the gate of the NMOS transistor and the PMOS transistor respectively, The gate voltage applied to the NMOS transistor and the PMOS transistor changes with the change of temperature, so that the product of the resistance value of the resistor and the capacitance value of the capacitor is 0 with respect to the change of temperature, Wherein, The current of the first voltage source electrically connected to the NMOS transistor is positive and decreases with the increase of temperature, so that the voltage applied to the gate of the NMOS transistor decreases with the increase of temperature; The current of the second voltage source electrically connected to the PMOS transistor is negative and increases with the increase of temperature, so that the voltage applied to the gate of the PMOS transistor increases with the increase of temperature.

2. The voltage regulator circuit of claim 1, wherein, When the temperature exceeds a predetermined threshold, the capacitance value of the capacitor decreases with the increase of temperature, and the resistance value of the resistor increases with the increase of temperature.

3. The voltage stabilizing circuit according to claim 1, wherein a magnitude of a resistance value of the resistor is 10 times a magnitude of a capacitance value of the capacitor when the resistance value of the resistor and the capacitance value of the capacitor are expressed in scientific notation. 19 The above.

4. The voltage regulator circuit of claim 1, wherein, The rear-stage voltage stabilizing module includes an LDO linear voltage stabilizing circuit, and the LDO linear voltage stabilizing circuit includes an error amplifier, and the error amplifier is a chop architecture or an auto-zero architecture.

5. The voltage regulator circuit according to any one of claims 1 to 4, wherein The reference voltage of the front-stage voltage stabilizing module is provided by a bandgap reference source, and the reference voltage of the rear-stage voltage stabilizing module is the output voltage of the low-pass filter module.

6. An electronic device, comprising: The electronic device includes the voltage stabilizing circuit of any one of claims 1 to 5.

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