Dual-threshold voltage stabilizing circuit, chip and energy storage equipment

Abstract

The embodiment of the invention provides a dual-threshold voltage stabilizing circuit, a chip and energy storage equipment. The dual-threshold voltage stabilizing circuit comprises a first voltage limiting control module, a second voltage limiting control module, a first switching tube, a second switching tube, a current mirror circuit and an MEMS charge pump, the output end of the first voltage limiting control module is connected with the input end of the first switching tube, and the input end of the first voltage limiting control module is connected with the voltage output end of the MEMS charge pump; the output end of the second voltage limiting control module is connected with the input end of the second switching tube, and the input end of the second voltage limiting control module is connected with the voltage output end of the MEMS charge pump; the first switch tube and the second switch tube are connected in parallel, are connected with the voltage input end of the MEMS charge pump, and are used for adjusting the output voltage value of the MEMS charge pump; and the second switch tube is connected in series with the current mirror circuit, so that the voltage limiting capability of the MEMS charge pump is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of energy storage devices, and specifically to a dual-threshold voltage stabilization circuit, a chip, and an energy storage device. Background Art

[0002] The charge pump topology is a commonly used boosting method in integrated circuits of energy storage devices. Among them, the Dickson charge pump is the most widely used. However, since the number of stages in the Dickson charge pump determines the final output voltage, the threshold voltage drop of its output is relatively high, and an additional clock signal oscillator is required to support it, which reduces the power efficiency of the charge pump system. Therefore, in order not to add an additional clock signal, a MEMS (micro-electromechanical system) charge pump is proposed.

[0003] The variable capacitor of the MEMS charge pump is a MEMS resonator, which is a mechanical structure composed of a spring damping system. When the system oscillates, the distance between the parallel plates of the capacitor changes, causing the capacitance value to change, thereby achieving a voltage boost.

[0004] However, since the oscillator of the MEMS charge pump is a mechanical structure, it takes a long time to resume oscillation after the oscillator stops, resulting in a decrease in its voltage limiting capability. Summary of the invention

[0005] In view of this, embodiments of the present application provide a dual-threshold voltage stabilization circuit, a chip, and an energy storage device to improve the voltage limiting capability of a MEMS charge pump.

[0006] To solve the above problems, an embodiment of the present application provides a dual-threshold voltage stabilization circuit, including: a first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump;

[0007] The output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, so as to control the working state of the first switch tube;

[0008] The output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, so as to control the working state of the second switch tube;

[0009] The first switch tube is connected in parallel with the second switch tube and is connected to the voltage input end of the MEMS charge pump for adjusting the output voltage value of the MEMS charge pump; wherein the second switch tube is connected in series with the current mirror circuit.

[0010] Optionally, the first voltage limiting control module has the same structure as the second voltage limiting control module, including: an operational amplifier and a first capacitor and a second capacitor connected in series;

[0011] Among them, the positive electrode of the first capacitor is connected to the voltage output terminal of the MEMS charge pump, the negative electrode of the first capacitor is connected to the positive electrode of the second capacitor, and the negative electrode of the second capacitor is connected to the ground terminal; and the first node on the series connection branch of the first capacitor and the second capacitor is connected to the negative input terminal of the operational amplifier; the positive input terminal of the operational amplifier is connected to the reference voltage; and the output terminal of the operational amplifier is connected to the corresponding switch tube.

[0012] Optionally, when the product of the ratio of the first capacitor to the sum of the first capacitor and the second capacitor and the voltage at the voltage output end of the MEMS charge pump is greater than the reference voltage, the operational amplifier outputs a low-level signal, and the switch connected to the operational amplifier is turned off;

[0013] When the product of the ratio of the first capacitor to the sum of the first capacitor and the second capacitor and the voltage at the voltage output end of the MEMS charge pump is less than the reference voltage, the operational amplifier outputs a high-level signal and the switch tube connected to the operational amplifier is turned on.

[0014] Optionally, if the first switch tube is turned on and the second switch tube is turned off, a first voltage threshold outputted by the voltage output terminal of the MEMS charge pump is obtained;

[0015] If the first switch tube is turned off and the second switch tube is turned on, a second voltage threshold outputted by the voltage output terminal of the MEMS charge pump is obtained.

[0016] Optionally, the current mirror circuit includes: a first field effect transistor, a second field effect transistor and a current bias circuit;

[0017] Among them, the positive electrode of the current bias circuit is connected to the system power supply, the negative electrode of the current bias circuit is connected to the source of the first field effect transistor, the drain of the first field effect transistor is connected to the ground terminal, the gate of the first field effect transistor is connected to the gate of the second field effect transistor, and the second node located on the connecting branch between the source of the first field effect transistor and the negative electrode of the current bias circuit is connected to the third node on the connecting branch between the gate of the first field effect transistor and the gate of the second field effect transistor; the source of the second field effect transistor is connected to the drain of the second switch tube, and the drain of the second switch tube is connected to the fourth node on the connecting branch between the drain of the first switch tube and the input end of the MEMS charge pump; the source of the second switch tube is connected to the system power supply, and the gate of the second switch tube is connected to the output end of the second voltage limiting control module; the source of the first switch tube is connected to the system power supply, and the gate of the first switch tube is connected to the output end of the first voltage limiting control module.

[0018] Optionally, the current bias circuit is used to adjust the charge transfer speed of the MEMS charge pump based on current regulation.

[0019] Optionally, when the output voltage of the voltage output terminal of the MEMS charge pump is less than a first voltage threshold, both the first switch tube and the second switch tube are turned on;

[0020] When the output voltage of the voltage output terminal of the MEMS charge pump is greater than a first voltage threshold and less than a second voltage threshold, the first switch tube is turned off and the second switch tube is turned on;

[0021] When the output voltage of the voltage output terminal of the MEMS charge pump is greater than a second voltage threshold, both the first switch tube and the second switch tube are turned off.

[0022] An embodiment of the present application also provides a chip, which includes the dual-threshold voltage stabilization circuit described above.

[0023] An embodiment of the present application also provides an energy storage device, which includes the dual-threshold voltage stabilization circuit as described above.

[0024] Compared with the prior art, the technical solution of the embodiment of the present application has the following advantages:

[0025] In the dual-threshold voltage stabilization circuit provided in the embodiment of the present application, by including a first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump, when the output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the first switch tube is controlled; and when the output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the second switch tube is controlled; further, when the first switch tube is connected in parallel with the second switch tube and connected to the voltage input end of the MEMS charge pump, the output voltage value of the MEMS charge pump is adjusted based on the working states of the first switch tube and the second switch tube, thereby improving the voltage limiting capability of the MEMS charge pump.

[0026] Furthermore, when the second switch tube is connected in series with the current mirror circuit, the charge transfer speed of the MEMS charge pump can be adjusted based on the current regulation of the current mirror circuit, thereby adjusting the rise time and ripple size of the MEMS charge pump output voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0028] Figure 1 It is a schematic diagram of the structure of Dickson charge pump;

[0029] Figure 2 It is a schematic diagram of the structure of a MEMS charge pump;

[0030] Figure 3 It is a schematic diagram of the structure of the variable capacitor in the MEMS charge pump;

[0031] Figure 4 is a schematic diagram of the structure of a dual-threshold voltage stabilization circuit provided in an embodiment of the present application;

[0032] Figure 5 is a schematic diagram of the structure of a first voltage limiting control module and a second voltage limiting control module provided in an embodiment of the present application;

[0033] Figure 6is a schematic diagram of the structure of a current mirror circuit provided in an embodiment of the present application;

[0034] Figure 7 is another structural schematic diagram of the dual-threshold voltage stabilization circuit provided in an embodiment of the present application;

[0035] Figure 8 It is a schematic diagram comparing the effects of the single-threshold voltage stabilization circuit provided in the embodiment of the present application and the dual-threshold voltage stabilization circuit of the present application. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] Charge pump topology is a commonly used boost method in integrated circuits, among which Dickson charge pump is the most widely used. Figure 1 The structural diagram of the Dickson charge pump is shown as an example. Figure 1 As shown in the figure, a switching diode (shown as D1, D2 and D3 respectively) and a capacitor (shown as C1, C2 and C3 respectively) form a one-stage architecture, and the n-stage architecture composed of the switching diode and the capacitor constitutes the Dickson charge pump. Based on the switching diode, the capacitor transfers the corresponding charge from one stage to another for charging and discharging. Among them, in each clock cycle of the Dickson charge pump, the charge of each stage is alternately increased and its voltage is transmitted to the next stage through the switching diode.

[0038] It can be seen that the number of stages in the Dickson charge pump determines the final output voltage, which also makes the threshold voltage drop of the Dickson charge pump output higher and requires additional clock signal oscillator support, reducing the power efficiency of the charge pump system.

[0039] Therefore, in order not to add an additional clock signal, a MEMS (micro-electromechanical system) charge pump is proposed. A MEMS charge pump is a charge pump that does not require an additional clock signal. Its structure is as follows Figure 2 As shown. Among them, the capacitors connected to the clock signal are variable capacitors (shown as C1', C2' and C3' in the figure respectively). Figure 3 The schematic diagram of the structure of the variable capacitor in the MEMS charge pump is shown as an example. Figure 3As shown, the variable capacitor is a MEMS resonator (shown as M in the figure), which is a mechanical structure composed of a spring damping system, k represents the elastic coefficient; b represents the total damping coefficient of the system. When the system oscillates, the distance between the parallel plates of the capacitor or the area directly opposite to the parallel plates of the capacitor will change, causing the capacitance value to change; wherein C(x) is the part that changes with the displacement of the system. According to the calculation formula for capacitor storage energy: Q = CV (Q is the charge stored on the capacitor plates; C is the capacitance value; V is the voltage between the capacitor plates), in the case of a fixed charge, the voltage between the capacitor plates will change based on the change in the capacitance value. Thus, by alternating the adjacent capacitance values, the charge of each level can be alternately increased and the voltage can be transmitted to the next level, thereby achieving the purpose of boosting.

[0040] In an optional implementation, in order for the charge pump to generate the expected output voltage, a voltage limiting module is required. However, the existing voltage limiting module only starts the clock signal oscillator when the output voltage is lower than the expected output voltage value. If the output voltage exceeds the expected voltage value, the clock signal oscillator is stopped to maintain the output voltage of the charge pump near the expected output voltage value.

[0041] However, this method of using a voltage limiting module is not suitable for a MEMS charge pump. This is mainly because the oscillator of the MEMS charge pump is a mechanical structure. When the oscillator stops, it takes a long time to resume oscillation, thereby reducing the voltage limiting capability of the MEMS charge pump.

[0042] In view of this, an embodiment of the present application provides an improved dual-threshold voltage stabilization circuit solution, wherein the dual-threshold voltage stabilization circuit includes a first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump. When the output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the first switch tube is controlled; and when the output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the second switch tube is controlled; further, when the first switch tube is connected in parallel with the second switch tube and connected to the voltage input end of the MEMS charge pump, the output voltage value of the MEMS charge pump is adjusted based on the working states of the first switch tube and the second switch tube, thereby improving the voltage limiting capability of the MEMS charge pump.

[0043] Furthermore, when the second switch tube is connected in series with the current mirror circuit, the charge transfer speed of the MEMS charge pump can be adjusted based on the current regulation of the current mirror circuit, thereby adjusting the rise time and ripple size of the MEMS charge pump output voltage.

[0044] Based on the above ideas, Figure 4 The schematic diagram of the structure of the dual-threshold voltage regulator circuit provided by the embodiment of the present application is shown as an example. Figure 4 As shown, the dual-threshold voltage stabilization circuit may include: a first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump.

[0045] The output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, so as to control the working state of the first switch tube. Specifically, the first voltage limiting control module can be based on the relationship between the output voltage Vout of the MEMS charge pump and the voltage threshold corresponding to the first voltage limiting control module, and output a corresponding control voltage signal VG1, so as to control the working state of the first switch tube based on the control voltage signal, that is, whether the first switch tube is turned on or off.

[0046] The output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, so as to control the working state of the second switch tube. Specifically, the second voltage limiting control module can be based on the relationship between the output voltage Vout of the MEMS charge pump and the voltage threshold corresponding to the second voltage limiting control module, and output a corresponding control voltage signal VG2, so as to control the working state of the second switch tube based on the control voltage signal, that is, whether the second switch tube is turned on or off.

[0047] The first switch tube is connected in parallel with the second switch tube and is connected to the voltage input terminal of the MEMS charge pump to adjust the output voltage value of the MEMS charge pump. The second switch tube is connected in series with the current mirror circuit.

[0048] It should be noted that the current mirror circuit is an analog electronic component that changes the reference current I REF The output current can be controlled. REF Increase, the driving current provided by the current mirror circuit is enhanced, thereby speeding up the switching speed of the switch tube and increasing the charge transfer rate between the two nodes, that is, increasing the charge transfer speed of the MEMS charge pump. REF The charge transfer rate between the two nodes is reduced, that is, the charge transfer speed of the MEMS charge pump is reduced. Therefore, by adjusting the reference current I REFThe charge transfer speed of the MEMS charge pump can be adjusted, thereby further adjusting the rise time and ripple size of the MEMS charge pump output voltage. REF Can be obtained from an external bandgap reference circuit.

[0049] In addition, based on Figure 4 For the dual threshold voltage regulator circuit shown, the output voltage formula of the MEMS charge pump can be:

[0050]

[0051] Where A is the gain of the first-stage MEMS charge pump, n is the number of MEMS charge pump stages; A n It is the gain of the n-stage MEMS charge pump. In actual situations, the threshold voltage of the switch tube needs to be subtracted. A=C max / C min , C max With C min is the maximum and minimum value of the variable capacitance generated by the MEMS oscillator during the oscillation process; V f is the threshold voltage of the switch tube; Vin is the input voltage of the MEMS charge pump;.

[0052] Vout is the MEMS charge pump output voltage.

[0053] It can be seen that the embodiment of the present application includes a first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump through a dual-threshold voltage stabilization circuit. When the output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the first switch tube is controlled; and when the output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the second switch tube is controlled; further, when the first switch tube is connected in parallel with the second switch tube and connected to the voltage input end of the MEMS charge pump, the output voltage value of the MEMS charge pump is adjusted based on the working states of the first switch tube and the second switch tube, thereby improving the voltage limiting capability of the MEMS charge pump.

[0054] Furthermore, when the second switch tube is connected in series with the current mirror circuit, the charge transfer speed of the MEMS charge pump can be adjusted based on the current regulation of the current mirror circuit, thereby adjusting the rise time and ripple size of the MEMS charge pump output voltage.

[0055] In some embodiments, the structures of the first voltage limiting control module and the second voltage limiting control module of the present application may be the same. Figure 5 The structural diagram of the first voltage limiting control module and the second voltage limiting control module in the embodiment of the present application is exemplarily shown.

[0056] like Figure 5 As shown, taking the first voltage limiting control module as an example, the first voltage limiting control module and the second voltage limiting control module with the same structure are described, which may include: an operational amplifier (Y1) and a first capacitor (C1) and a second capacitor (C2) connected in series.

[0057] The positive electrode of the first capacitor C1 is connected to the voltage output terminal Vout of the MEMS charge pump, the negative electrode of the first capacitor C1 is connected to the positive electrode of the second capacitor C2, and the negative electrode of the second capacitor C2 is connected to the ground terminal. In addition, the first node T1 on the series connection branch of the first capacitor C1 and the second capacitor C2 is connected to the negative input terminal of the operational amplifier Y1. The positive input terminal of the operational amplifier Y1 is connected to the reference voltage V REF The output terminal V of the operational amplifier Y1 G1 Connect the corresponding switch tube (ie, the first switch tube).

[0058] In some embodiments, based on the structure of the voltage limiting control module, taking the first voltage limiting control module as an example, the working state of the corresponding switch tube controlled by the first voltage limiting control module is described.

[0059] As an optional implementation, when the product of the ratio of the first capacitor C1 to the sum of the first capacitor C1 and the second capacitor C2 and the voltage at the voltage output terminal of the MEMS charge pump is greater than the reference voltage V REF When: V out *C 1 / (C 1 +C 2 )>V REF , the operational amplifier can output a low-level signal, so that the switch tube (ie, the first switch tube) connected to the operational amplifier is turned off.

[0060] As another optional implementation, when the product of the ratio of the first capacitor C1 to the sum of the first capacitor C1 and the second capacitor C2 and the voltage at the voltage output terminal of the MEMS charge pump is less than the reference voltage V REF When: V out *C 1 / (C 1 +C 2 ) <V REF , the operational amplifier can output a high-level signal, so that the switch tube (ie, the first switch tube) connected to the operational amplifier is turned on.

[0061] In some further embodiments, based on the control of the working state of the switch tube by the voltage limiting control module, if the first switch tube in the dual-threshold voltage stabilization circuit is turned on and the second switch tube is turned off, the first voltage threshold V outputted by the voltage output terminal of the MEMS charge pump can be obtained. lim1 . See the following formula:

[0062]

[0063] If the first switch in the dual-threshold voltage regulator circuit is turned off and the second switch is turned on, the second voltage threshold V outputted from the voltage output terminal of the MEMS charge pump can be obtained. lim2 . See the following formula:

[0064]

[0065] It can be understood that, corresponding to the working state of the first switch tube and the second switch tube, the first voltage threshold V lim1 and the second voltage threshold V lim2 can be two thresholds of the output voltage Vout of the MEMS charge pump. And, based on design requirements, V lim2 It can be set to the expected output voltage of the MEMS charge pump. The embodiment of the present application can also design other expected output voltages based on other requirements, and the embodiment itself is not limited to this.

[0066] In some embodiments, Figure 6 The structural diagram of the current mirror circuit of the embodiment of the present application is exemplarily shown. Figure 6 As shown, the current mirror circuit may include: a first field effect transistor A1, a second field effect transistor A2 and a current bias circuit P1.

[0067] Among them, the positive electrode of the current bias circuit P1 is connected to the system power supply VDD, the negative electrode of the current bias circuit P1 is connected to the source of the first field effect transistor A1, the drain of the first field effect transistor A1 is connected to the ground terminal, the gate of the first field effect transistor A1 is connected to the gate of the second field effect transistor A2, and the second node T2 located on the connecting branch between the source of the first field effect transistor A1 and the negative electrode of the current bias circuit P1 is connected to the third node T3 on the connecting branch between the gate of the first field effect transistor A1 and the gate of the second field effect transistor A2.

[0068] The source of the second field effect transistor A2 is connected to the second switch transistor ( Figure 6 The drain of the second field effect transistor A2 is connected to the drain of the first switch tube ( Figure 6 The drain of the MEMS charge pump is connected to the input terminal Vin The connecting branch is connected to the fourth node T4.

[0069] The source of the second switch tube SW2 is connected to the system power supply VDD, and the gate of the second switch tube SW2 is connected to the output terminal V G2 .

[0070] The source of the first switch tube SW1 is connected to the system power supply VDD, and the gate of the first switch tube SW1 is connected to the output terminal V G1 .

[0071] In some embodiments, the current bias circuit in the current mirror circuit can be used to adjust the charge transfer speed of the MEMS charge pump based on current regulation.

[0072] In some embodiments, based on the structure of the dual-threshold voltage regulator circuit of the embodiment of the present application, when the output voltage of the voltage output terminal of the MEMS charge pump is less than the first voltage threshold, that is: V out <V lim1 , the first switch tube SW1 and the second switch tube SW2 are both turned on, at this time, the output voltage Vout of the MEMS charge pump will rise rapidly.

[0073] When the output voltage of the voltage output terminal of the MEMS charge pump is greater than the first voltage threshold and less than the second voltage threshold, that is: V lim1 <V out <V lim2 , the first switch tube SW1 is turned off, and the second switch tube SW2 is turned on. At this time, the output voltage Vout of the MEMS charge pump rises slowly.

[0074] When the output voltage of the voltage output terminal of the MEMS charge pump is greater than the second voltage threshold, that is: V lim2 <V out , the first switch tube SW1 and the second switch tube SW2 are both turned off, at this time, the output voltage Vout of the MEMS charge pump will decrease.

[0075] It should be noted that based on V lim2 is the expected output voltage of the MEMS charge pump. To achieve a stable output voltage of the MEMS charge pump at V lim2 , the first switch tube SW1 can be turned off, the second switch tube SW2 can be turned on, and the first switch tube SW1 and the second switch tube SW2 can be turned off repeatedly.

[0076] In order to verify the voltage limiting effect of the dual threshold voltage stabilization circuit of the present application, Figure 7Another structural schematic diagram of the dual-threshold voltage stabilization circuit of an embodiment of the present application is exemplarily shown. Figure 8 The schematic diagram for comparing the effects of a single-threshold voltage regulator circuit and a dual-threshold voltage regulator circuit of the present application is exemplarily shown.

[0077] See also Figure 8 As shown, the dual-threshold voltage stabilization circuit of the embodiment of the present application can achieve better voltage stabilization effect than the single-threshold voltage stabilization circuit, and improve the continuous operation response capability of the MEMS charge pump. In addition, the dual-threshold voltage stabilization circuit of the embodiment of the present application has smaller ripple than the single-threshold circuit, which speeds up the voltage stabilization speed.

[0078] The embodiment of the present application includes a dual-threshold voltage stabilization circuit including a first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump. When the output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the first switch tube is controlled; and when the output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, the working state of the second switch tube is controlled; further, when the first switch tube is connected in parallel with the second switch tube and connected to the voltage input end of the MEMS charge pump, the output voltage value of the MEMS charge pump is adjusted based on the working states of the first switch tube and the second switch tube, thereby improving the voltage limiting capability of the MEMS charge pump.

[0079] Furthermore, when the second switch tube is connected in series with the current mirror circuit, the charge transfer speed of the MEMS charge pump can be adjusted based on the current regulation of the current mirror circuit, thereby adjusting the rise time and ripple size of the MEMS charge pump output voltage.

[0080] An embodiment of the present application also provides a chip, which includes a dual-threshold voltage stabilization circuit as provided in the embodiment of the present application.

[0081] An embodiment of the present application also provides an energy storage device, which may be, for example, a battery, a lithium battery cell, a mobile power supply, a photovoltaic energy storage device, etc. The energy storage device may include a dual-threshold voltage stabilization circuit as provided in an embodiment of the present application.

[0082] The above describes multiple implementation schemes provided by the embodiments of the present application. The various optional methods introduced in each implementation scheme can be combined and cross-referenced with each other without conflict, thereby extending a variety of possible implementation schemes, which can all be considered as implementation schemes disclosed and open in the embodiments of the present application.

[0083] Although the embodiments of the present application are disclosed above, the present application is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be subject to the scope defined by the claims.

Claims

1. A dual-threshold voltage stabilizing circuit, characterized in that: include: A first voltage limiting control module, a second voltage limiting control module, a first switch tube, a second switch tube, a current mirror circuit and a MEMS charge pump; The output end of the first voltage limiting control module is connected to the input end of the first switch tube, and the input end of the first voltage limiting control module is connected to the voltage output end of the MEMS charge pump, so as to control the working state of the first switch tube; The output end of the second voltage limiting control module is connected to the input end of the second switch tube, and the input end of the second voltage limiting control module is connected to the voltage output end of the MEMS charge pump, so as to control the working state of the second switch tube; The first switch tube is connected in parallel with the second switch tube and is connected to the voltage input end of the MEMS charge pump for adjusting the output voltage value of the MEMS charge pump; wherein the second switch tube is connected in series with the current mirror circuit.

2. The dual-threshold voltage regulator circuit according to claim 1, characterized in that: The first voltage limiting control module has the same structure as the second voltage limiting control module, including: an operational amplifier and a first capacitor and a second capacitor connected in series; Among them, the positive electrode of the first capacitor is connected to the voltage output terminal of the MEMS charge pump, the negative electrode of the first capacitor is connected to the positive electrode of the second capacitor, and the negative electrode of the second capacitor is connected to the ground terminal; and the first node on the series connection branch of the first capacitor and the second capacitor is connected to the negative input terminal of the operational amplifier; the positive input terminal of the operational amplifier is connected to the reference voltage; and the output terminal of the operational amplifier is connected to the corresponding switch tube.

3. The dual-threshold voltage regulator circuit according to claim 2, characterized in that: When the product of the ratio of the first capacitor to the sum of the first capacitor and the second capacitor and the voltage at the voltage output end of the MEMS charge pump is greater than the reference voltage, the operational amplifier outputs a low level signal, and the switch connected to the operational amplifier is turned off; When the product of the ratio of the first capacitor to the sum of the first capacitor and the second capacitor and the voltage at the voltage output end of the MEMS charge pump is less than the reference voltage, the operational amplifier outputs a high-level signal and the switch tube connected to the operational amplifier is turned on.

4. The dual-threshold voltage stabilizing circuit according to claim 3, characterized in that: If the first switch tube is turned on and the second switch tube is turned off, a first voltage threshold outputted by the voltage output terminal of the MEMS charge pump is obtained; If the first switch tube is turned off and the second switch tube is turned on, a second voltage threshold outputted by the voltage output terminal of the MEMS charge pump is obtained.

5. The dual-threshold voltage regulator circuit according to claim 4, characterized in that: The current mirror circuit comprises: a first field effect transistor, a second field effect transistor and a current bias circuit; Among them, the positive electrode of the current bias circuit is connected to the system power supply, the negative electrode of the current bias circuit is connected to the source of the first field effect transistor, the drain of the first field effect transistor is connected to the ground terminal, the gate of the first field effect transistor is connected to the gate of the second field effect transistor, and the second node located on the connecting branch between the source of the first field effect transistor and the negative electrode of the current bias circuit is connected to the third node on the connecting branch between the gate of the first field effect transistor and the gate of the second field effect transistor; the source of the second field effect transistor is connected to the drain of the second switch tube, and the drain of the second switch tube is connected to the fourth node on the connecting branch between the drain of the first switch tube and the input end of the MEMS charge pump; the source of the second switch tube is connected to the system power supply, and the gate of the second switch tube is connected to the output end of the second voltage limiting control module; the source of the first switch tube is connected to the system power supply, and the gate of the first switch tube is connected to the output end of the first voltage limiting control module.

6. The dual-threshold voltage regulator circuit according to claim 5, characterized in that: The current bias circuit is used to adjust the charge transfer speed of the MEMS charge pump based on current regulation.

7. The dual-threshold voltage regulator circuit according to claim 5, characterized in that: When the output voltage of the voltage output terminal of the MEMS charge pump is less than a first voltage threshold, the first switch tube and the second switch tube are both turned on; When the output voltage of the voltage output terminal of the MEMS charge pump is greater than a first voltage threshold and less than a second voltage threshold, the first switch tube is turned off and the second switch tube is turned on; When the output voltage of the voltage output terminal of the MEMS charge pump is greater than a second voltage threshold, both the first switch tube and the second switch tube are turned off.

8. A chip, characterized in that: The dual-threshold voltage regulator circuit comprises the dual-threshold voltage regulator circuit as described in any one of claims 1 to 7.

9. An energy storage device, characterized in that: It comprises a dual-threshold voltage regulator circuit as claimed in any one of claims 1 to 7.

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