Signal generator
Through the signal output stage and negative voltage generation circuit in the signal generator, combined with the sensor and charge pump circuit, the output voltage driving capability is dynamically adjusted, and the reliability and flexibility of integrated audio output stages in the prior art are solved, achieving the output of high-quality signals and the satisfaction of national standards.
Patent Information
- Application Number
- CN202311852486.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-28
- Publication Date
- 2025-07-08
AI Technical Summary
In the case where the power supply voltage of the audio and video receiver chip is not increased, it is difficult to develop integrated audio output stages in the deep submicron process. The use of negative voltages brings reliability risks and cannot meet the national standard requirements under different loads and environments, resulting in loss or deterioration of output signal performance.
Through the signal output stage circuit and negative voltage generation circuit in the signal generator, combined with the sensor sensing load demand and operating voltage, dynamically adjust the driving capability of the output voltage, use the switching components and charge pump circuit to adjust the number of enabled signals output sub-circuits and negative voltage generation circuits, and realize multi-stage adjustment to adapt to different load and voltage environments.
It realizes the output of high-quality signals under different load and power environments, meets the national standard requirements, improves the reliability and flexibility of the signal generator, and avoids the sharp deterioration of circuit performance.
Smart Images
Figure CN120281971A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a signal generator, and more particularly to a signal generator for an audio transceiver device. Background Art
[0002] The audio output stage of an audio-video receiver and player (hereinafter simply referred to as "audio-video receiver") can be used to output processed audio signals. Since it is necessary to meet the requirements of national standards for signal amplitude and the amplitude needs to be greater than the power supply voltage during chip operation, the audio output stage module usually cascades discrete components such as amplifiers on the printed circuit board (which operate under high power supply voltage) to meet the large swing requirement.
[0003] The prior art proposes to develop an integrated audio output stage in deep sub-micron technology without increasing the power supply voltage of the audio-video receiver chip, and use a negative voltage regulator, the generated negative voltage can increase the upper limit that the output signal swing can reach, so as to meet the national standard requirements.
[0004] However, for the integrated audio output stage developed by these technologies, the use of negative voltage may bring reliability risks. And for different loads, different standard requirements, and different power supply operating environments, if the design parameters of relevant modules cannot be flexibly adjusted, there is a risk of loss of output signal performance. Even in the presence of certain peripheral load environments, the output signal performance will deteriorate sharply, resulting in non-compliance with national standard requirements.
[0005] In addition, with the increasing market demand for audio output stages in low-cost and high-performance audio-video receivers, people hope that audio-video receivers use integrated audio output stages that can directly output high-quality signals meeting national standard requirements. However, the reliability risks brought by the introduction of negative voltage in the circuit, as well as the flexibility requirements in different peripheral load environments, have severely restricted the use of integrated audio output stages that meet national standard requirements and can output high-quality signals. Summary of the Invention
[0006] The present invention is directed to a signal generator that can dynamically adjust the electrical characteristics of the output voltage according to the load state and the voltage value of the operating voltage.
[0007] According to an embodiment of the present invention, the signal generator includes a signal output stage circuit, a sensor, and a negative voltage generation circuit. The signal output stage circuit receives the operating voltage and the negative voltage as the power supply voltage, and generates an output voltage to drive the load. The sensor senses the load demand of the load and the voltage value of the operating voltage. The negative voltage generation circuit adjusts the driving ability of the negative voltage according to the relevant information of the voltage value and the relevant information of the load demand. Among them, the signal output stage circuit adjusts the driving ability of the output voltage according to the relevant information of the load demand. Brief Description of the Drawings
[0008] Figure 1 It is a schematic diagram of a signal generator according to an embodiment of the present invention.
[0009] Figure 2 It is a schematic diagram of an implementation manner of an output stage circuit according to an embodiment of the present invention.
[0010] Figure 3 It is a schematic diagram of implementation details of a negative voltage generation circuit according to an embodiment of the present invention.
[0011] Figure 4 It is a schematic diagram of an implementation manner of a charge pump circuit according to an embodiment of the present invention.
[0012] Figure 5 It is a block diagram of an implementation manner of a signal generator according to another embodiment of the present invention.
[0013] Figure 6 It is a schematic diagram of an operation for adjusting the enabled number of charge pump circuits of a negative voltage generation circuit 520 in an embodiment of the present invention. Detailed implementation manner
[0014] Now, exemplary embodiments of the present invention will be described in detail, and examples of the exemplary embodiments are illustrated in the accompanying drawings. As long as possible, the same component symbols are used in the drawings and the description to represent the same or similar parts.
[0015] Please refer to Figure 1 , Figure 1 It is a schematic diagram of a signal generator according to an embodiment of the present invention. The signal generator 100 includes a signal output stage circuit 110, a negative voltage generation circuit 120, and a sensor 130. The signal generator 100 can be a part of an audio signal transceiver device. The signal output stage circuit 110 receives an operating voltage VPP and a negative voltage Vneg as power supply voltages. The output terminal of the signal output stage circuit 110 is coupled to a load 101. The signal output stage circuit 110 is used to generate an output voltage Vo at its output terminal to drive the load 101. The negative voltage generation circuit 120 is coupled to the signal output stage circuit 110 and is used to generate the negative voltage Vneg. The negative voltage generation circuit 120 is further coupled to a capacitor Cfly, where the capacitor Cfly is used to store charge and serves as a source of the output current of the negative voltage Vneg. The output voltage Vo generated by the signal output stage circuit 110 can swing between the operating voltage VPP and the negative voltage Vneg.
[0016] The sensor 130 is coupled to the operating voltage VPP and to the load 101. The sensor 130 can be used to sense the voltage value of the operating voltage VPP and to sense the load demand of the load 101, and thereby obtain information related to the voltage value of the operating voltage VPP and information related to the load demand of the load 101. Among them, the sensor 130 can include a voltage sensor to sense the voltage value of the operating voltage VPP and a load sensor to sense the load demand of the load 101. The load sensor can apply a test vector to the load 101, thereby obtain a feedback signal, and obtain information related to the load demand of the load 101 according to the feedback signal. The above-mentioned voltage sensor and load sensor can both be implemented by voltage and load sensing circuits well-known to those of ordinary skill in the art, without specific limitations.
[0017] On the other hand, the sensor 130 can transmit the sensed intensity ST1 of the operating voltage VPP and the intensity ST2 of the load demand of the load 101 to the negative voltage generation circuit 120. In addition, the sensor 130 can respectively generate control data (control bits) CS1 and CS2 according to the sensed voltage value of the operating voltage VPP and the load demand of the load 101, and transmit the control data CS1 and CS2 to the signal output stage circuit 110. Among them, in the embodiments of the present invention, the intensities ST1 and ST2 can be information in the same format as the control data CS1 and CS2 respectively. Or, in other embodiments of the present invention, the control data CS1 and CS2 can be digital information of multiple bits, and the intensities ST1 and ST2 can be analog information.
[0018] To further illustrate, the signal output stage circuit 110 can adjust the driving ability of the generated output voltage Vo according to the received control data CS1 and CS2. The negative voltage generation circuit 120 can adjust the driving ability of the generated negative voltage Vneg according to the intensities ST1 and ST2.
[0019] Specifically, please refer to Figure 1 and Figure 2 , where Figure 2It is a schematic diagram of an implementation manner of a signal output stage circuit according to an embodiment of the present invention. The signal output stage circuit 110 includes a plurality of signal output sub-circuits 211 to 21N. A plurality of output terminals of the signal output sub-circuits 211 to 21N can be commonly coupled to an output terminal OE of the signal output stage circuit 110. In this embodiment, the plurality of output terminals of the signal output sub-circuits 211 to 21N can be coupled to the output terminal OE of the signal output stage circuit 110 through a switch component 220. Specifically, the signal output stage circuit 110 can adjust the number of enabled signal output sub-circuits among the signal output sub-circuits 211 to 21N according to relevant information on the load demand provided by the sensor 130. Among them, the switch component 220 can be used to receive control data CS1 and CS2, and obtain relevant information such as the voltage value of the operating voltage VPP and the load demand of the load 101 through the control data CS1 and CS2. The switch component 220 can determine the number of output terminals of the signal output sub-circuits 211 to 21N that are connected to the output terminal OE of the signal output stage circuit 110 according to the control data CS2, so as to control the number of enabled signal output sub-circuits among the signal output sub-circuits 211 to 21N. It is worth mentioning that during normal operation, at least one of the signal output sub-circuits 211 to 21N is coupled to the output terminal OE of the signal output stage circuit 110; during standby, the signal output sub-circuits 211 to 21N are all disconnected from the output terminal OE of the signal output stage circuit 110.
[0020] In this embodiment, each of the signal output sub-circuits 211 to 21N can have the same circuit architecture. Taking the signal output sub-circuit 211 as an example, the signal output sub-circuit 211 can include a transistor M1 and a transistor M2. A first end of the transistor M1 receives the operating voltage VPP; a control end of the transistor M1 can receive an input voltage VI1; a second end of the transistor M1 is coupled to a first end of the transistor M2 to generate an output voltage Vo; a control end of the transistor M2 receives an input voltage VI2; a second end of the transistor M2 receives a negative voltage Vneg. The transistor M1 can be a P-type transistor, and the transistor M2 can be an N-type transistor.
[0021] Incidentally, the transistors M1 and M2 can be transistors of any form and are not particularly limited. And, in this embodiment, the total number of the signal output sub-circuits 211 to 21N can be set according to the actual needs of the audio signal transceiver device and is not limited.
[0022] It should be noted that in this embodiment, the number of signal output sub - circuits 211 - 21N enabled can be adjusted by the switch component 220. In other embodiments of the present invention, the switch component 220 may not be used, and instead, the number of enabled signal output sub - circuits 211 - 21N is determined according to the control data CS2. Among them, the signal output sub - circuits 211 - 21N that are not enabled are disabled and do not participate in the generation operation of the output voltage Vo.
[0023] Please refer back to Figure 1 Regarding the implementation details of the negative voltage generation circuit 120, please refer to the following Figure 3 and Figure 1 , where Figure 3 is a schematic diagram of the implementation details of the negative voltage generation circuit in an embodiment of the present invention. The negative voltage generation circuit 120 includes a plurality of charge pump circuits 311 - 31M. The multiple output terminals of the charge pump circuits 311 - 31M can be commonly coupled to the output terminal OE1 of the negative voltage generation circuit 120. The negative voltage generation circuit 120 receives the intensity ST1 of the operating voltage VPP and the intensity ST2 of the load demand of the load 101, and determines the number of enabled charge pump circuits 311 - 31M according to the intensity ST1 and the intensity ST2.
[0024] Regarding the implementation details of the charge pump circuits 311 - 31M, reference can be made to Figure 4 a schematic diagram of the implementation manner of the charge pump circuit in an embodiment of the present invention. In Figure 4 , taking the charge pump circuit 311 as an example, the charge pump circuit 311 includes switches SW1 - SW4, and capacitors Cfly and C2. Among them, the first terminal of the switch SW1 receives the basic voltage V +; the second terminal of the switch SW1 is coupled to the first terminal of the capacitor Cfly; the first terminal of the switch SW2 is coupled to the first terminal of the capacitor Cfly, and the second terminal of the switch SW2 receives the ground voltage GND; the first terminal of the switch SW3 receives the ground voltage GND, and the second terminal of the switch SW3 is coupled to the second terminal of the capacitor Cfly; the first terminal of the switch SW4 is coupled to the second terminal of the capacitor Cfly, and the second terminal of the switch SW4 is coupled to the first terminal of the capacitor C2. In addition, the first terminal of the capacitor C2 is used to generate the negative voltage Vneg, and the second terminal of the capacitor C2 receives the ground voltage GND.
[0025] In the initial state (such as the default state, when powered on or entering standby), all switches SW1 - SW4 are open. When discharging the capacitor Cfly, switches SW2 and SW3 can be respectively turned on according to control signals S2 and S3 simultaneously, and switches SW1 and SW4 are respectively turned off (opened) according to control signals S1 and S4. At this time, the capacitor Cfly can perform a discharging operation and discharge the stored charge inside. When generating the negative voltage Vneg, in the first stage, switches SW1 and SW3 can be respectively turned on according to control signals S1 and S3 (switches SW2 and SW4 are turned off), and the capacitor Cfly is charged. At this time, the voltage on the positive terminal of the capacitor Cfly can be equal to the basic voltage V+, and the voltage on the negative terminal of the capacitor Cfly is equal to the ground voltage GND. Then, in the second stage, switches SW2 and SW4 can be respectively turned on according to control signals S2 and S4 (switches SW1 and SW3 change to be turned off). At this time, the positive terminal of the capacitor Cfly receives the ground voltage GND, and the negative terminal of the capacitor Cfly is connected to the first terminal of the capacitor C2. At this time, the capacitors Cfly and C2 can perform charge sharing, and a negative voltage Vneg is generated on the first terminal of the capacitor C2.
[0026] The above - mentioned first stage and second stage can be repeatedly executed, and charges can be cumulatively stored in the capacitor C2. In this way, the capacitor C2 can make the negative voltage Vneg have sufficient driving ability.
[0027] Here, please note that in Figure 3 the embodiment, multiple charge pump circuits 311 - 31M can share the same capacitor C2. Multiple charge pump circuits 311 - 31M can share the same capacitor Cfly. In other embodiments of the present invention, multiple charge pump circuits 311 - 31M may not share the capacitor Cfly and may respectively have independent capacitors Cfly.
[0028] Please refer back to Figure 1 , regarding the signal generator 100 of the embodiment of the present invention, the method of determining the number of enabled signal output sub - circuits and the number of enabled charge pump circuits can be as described below. Among them, the signal output stage circuit 110 can preset a first load threshold, and when it determines that the load demand is greater than the first load threshold, it sets the signal generator 100 to the overload state and makes the number of enabled signal output sub - circuits be the first number. And when the signal output stage circuit 110 determines that the load demand is not greater than the first load threshold, it sets the signal generator 100 to the light - load state. The signal output stage circuit 110 can make the number of enabled signal output sub - circuits be the second number. Wherein the first number is greater than the second number.
[0029] The negative voltage generation circuit 120 can additionally set a first voltage threshold. When the load demand is greater than the above-mentioned first load threshold and the voltage value of the operating voltage VPP is greater than the first voltage threshold (high operating voltage), the number of charge pump circuits enabled by the negative voltage generation circuit 120 is the first number. When the load demand is greater than the first load threshold and the voltage value of the operating voltage VPP is not greater than the first voltage threshold (low operating voltage), the number of charge pump circuits enabled by the negative voltage generation circuit 120 is the second number. When the load demand is not greater than the first load threshold and the voltage value of the operating voltage VPP is greater than the first voltage threshold (high operating voltage), the number of charge pump circuits enabled by the negative voltage generation circuit 120 is the third number. And when the load demand is not greater than the first load threshold and the voltage value of the operating voltage VPP is not greater than the first voltage threshold (low operating voltage), the number of charge pump circuits enabled by the negative voltage generation circuit 120 is the fourth number. Among them, the above-mentioned second number > the above-mentioned fourth number = the above-mentioned first number > the above-mentioned third number.
[0030] The above description can be organized as the following table:
[0031]
[0032] In addition, in other embodiments of the present invention, the signal output stage circuit 110 can also pre-set multiple load thresholds (such as a first load threshold and a second load threshold). When the load demand is greater than the first load threshold (heavy load state), the number of signal output sub-circuits enabled by the signal output stage circuit 110 is the first number; when the load demand is less than the second load threshold (light load state), the number of signal output sub-circuits enabled by the signal output stage circuit 110 is the second number; when the load demand is between the first load threshold and the second load threshold (medium load state, or standard state), the number of signal output sub-circuits enabled by the signal output stage circuit 110 is the third number, where the first load threshold is greater than the second load threshold, the first number is greater than the third number, and the third number can be greater than the second number.
[0033] From the above description, it can be known that in the embodiments of the present invention, multiple load thresholds and multiple voltage thresholds can be set to determine the load demand state and the voltage value state of the operating voltage, and the driving capabilities of the output voltage Vo and the negative voltage Vneg generated by the signal output stage circuit 110 and the negative voltage generation circuit 120 can be adjusted in multiple stages according to the determined load demand state and the voltage value state of the operating voltage, thereby improving the working efficiency of the signal generator 100. Please refer to Figure 5 , Figure 5It is a block diagram of an implementation manner of a signal generator according to another embodiment of the present invention. The signal generator 500 includes a signal output stage circuit 510, a negative voltage generation circuit 520, a sensor 530, and a ramp signal generator 540. The signal generator 500 can be a part of an audio signal transceiver device and is used to generate an output voltage Vo to drive a load 501. Among them, the signal generator 500 is generally similar to Figure 1 the signal generator 100 of the embodiment, and the same parts will not be elaborated here. Different from the foregoing embodiment, a ramp signal generator 540 is additionally provided in the signal generator 500. The ramp signal generator 540 is coupled to the negative voltage generation circuit 520 and is used to generate a ramp signal RMP. The ramp signal RMP can have a voltage value that gradually increases (or decreases) according to a preset slope. When the negative voltage generation circuit 520 needs to adjust the number of charge pump circuits therein, each charge pump circuit can be enabled or disabled one by one according to the state of the voltage value of the ramp signal RMP.
[0034] Please refer synchronously to the following Figure 5 and Figure 6 , where Figure 6 is a schematic diagram of the operation of adjusting the enabled number of the charge pump circuits of the negative voltage generation circuit 520 in the embodiment of the present invention. In Figure 6In [description], the negative voltage generation circuit 520 includes four charge pump circuits 611 to 614. The charge pump circuits 611 to 614 each have four output terminals E1 to E4, and the negative voltage generation circuit 520 has an output terminal OE1. In the initial state (e.g., the default state, when powering on or entering standby), all switches are open; when entering state T0, the capacitor Cfly is discharged. That is, both ends of the capacitor Cfly receive the ground voltage GND, so that the charge in the capacitor Cfly can be discharged. Then, when the charge pump circuits 611 to 614 are to be enabled one by one, the negative voltage generation circuit 520 can enter four states T1 to T4 in sequence according to the rising state of the voltage value of the ramp signal RMP. In state T1, the negative voltage generation circuit 520 only couples the output terminal E1 of the charge pump circuit 611 to the output terminal OE1 of the negative voltage generation circuit 520, so that the number of enabled charge pump circuits 611 to 614 = 1; then, in state T2, the negative voltage generation circuit 520 couples the output terminals E1 and E2 of the charge pump circuits 611 and 612 to the output terminal OE1 of the negative voltage generation circuit 520, so that the number of enabled charge pump circuits 611 to 614 = 2; in state T3, the negative voltage generation circuit 520 couples the output terminals E1, E2, and E3 of the charge pump circuits 611, 612, and 613 to the output terminal OE1 of the negative voltage generation circuit 520, so that the number of enabled charge pump circuits 611 to 614 = 3; finally, in state T4, the negative voltage generation circuit 520 couples the output terminals E1, E2, E3, and E4 of the charge pump circuits 611, 612, 613, and 614 to the output terminal OE1 of the negative voltage generation circuit 520, so that the number of enabled charge pump circuits 611 to 614 = 4.
[0035] Those skilled in the art can understand that when the chip is placed in the atmospheric environment, due to various reasons, charges will inevitably accumulate on the board capacitors. For example, the charges generated by static electricity may accumulate on the capacitor Cfly. When the capacitor Cfly starts charging and discharging instantaneously, these charges may impact the inside of the chip. At the same time, due to physical laws, the voltage across the capacitor Cfly cannot change suddenly. Therefore, an instantaneous large current will be generated at the moment of starting charging and discharging, which may also impact the inside of the chip. The two factors of the accumulated charges on the capacitor Cfly and the instantaneous large current during charging and discharging will both affect the reliability of the chip. For this reason, in this application, before the capacitor Cfly charges and discharges, the switches SW2 and SW3 are turned on, and the switches SW1 and SW4 are turned off, so that the capacitor Cfly is isolated from other parts of the circuit, and both ends of the capacitor Cfly are grounded to achieve full discharge of the charges. After that, by enabling the charge pump circuits 611 to 614 one by one, the phenomenon of large current generated during charging and discharging can be suppressed, the safety during the operation of the circuit components can be effectively maintained, and the possible electromagnetic interference can be suppressed.
[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention.
Claims
1. A signal generator, characterized in that, Comprising: A signal output stage circuit that receives an operating voltage and a negative voltage as power supply voltages and generates an output voltage to drive a load; A sensor that senses the load demand of the load and the voltage value of the operating voltage; And A negative voltage generation circuit that adjusts the driving ability of the negative voltage according to relevant information of the voltage value and relevant information of the load demand, wherein the signal output stage circuit adjusts the driving ability of the output voltage according to relevant information of the load demand.
2. The signal generator according to claim 1, characterized in that, The signal output stage circuit includes a plurality of signal output sub-circuits, and the signal output stage circuit adjusts the number of the plurality of signal output sub-circuits enabled according to relevant information of the load demand.
3. The signal generator according to claim 2, wherein When the load demand is greater than a first load threshold, the signal output stage circuit enables the number of the plurality of signal output sub-circuits to be a first number; when the load demand is not greater than the first load threshold, the signal output stage circuit enables the number of the plurality of signal output sub-circuits to be a second number, wherein the first number is greater than the second number.
4. The signal generator according to claim 2, characterized in that When the load demand is greater than a first load threshold, the signal output stage circuit enables the number of the plurality of signal output sub-circuits to be a first number; when the load demand is less than a second load threshold, the signal output stage circuit enables the number of the plurality of signal output sub-circuits to be a second number; when the load demand is between the first load threshold and the second load threshold, the signal output stage circuit enables the number of the plurality of signal output sub-circuits to be a third number, wherein the first load threshold is greater than the second load threshold, the first number is greater than the third number, and the third number is greater than the second number.
5. The signal generator according to claim 2, characterized in that, Each of the plurality of signal output sub-circuits includes: A first transistor, wherein a first end of the first transistor receives the operating voltage, a control end of the first transistor receives a first input voltage, and a second end of the first transistor generates an output voltage; and A second transistor, wherein a first end of the second transistor generates the output voltage, a control end of the second transistor receives a second input voltage, and a second end of the second transistor receives the negative voltage.
6. The signal generator according to claim 1, wherein, The negative voltage generation circuit includes a plurality of charge pump circuits, output ends of the plurality of charge pump circuits are coupled to each other, and the negative voltage generation circuit adjusts the number of the plurality of charge pump circuits enabled according to relevant information of the load demand and relevant information of the voltage value.
7. The signal generator according to claim 6, characterized in that, When the load demand is greater than a first load threshold and the voltage value is greater than a first voltage threshold, the negative voltage generation circuit enables the number of the plurality of charge pump circuits to be a first number; When the load demand is greater than the first load threshold and the voltage value is not greater than the first voltage threshold, the negative voltage generation circuit enables the plurality of charge pump circuits in a second quantity; when the load demand is not greater than the first load threshold and the voltage value is greater than the first voltage threshold, the negative voltage generation circuit enables the plurality of charge pump circuits in a third quantity; when the load demand is not greater than the first load threshold and the voltage value is not greater than the first voltage threshold, the negative voltage generation circuit enables the plurality of charge pump circuits in a fourth quantity, wherein the second quantity > the fourth quantity = the first quantity > the third quantity.
8. The signal generator according to claim 6, characterized in that, The negative voltage generation circuit starts the plurality of charge pump circuits in a time-sharing manner according to a ramp signal.
9. The signal generator according to claim 8, characterized in that, Further comprising: A ramp signal generator, coupled to the negative voltage generation circuit, for generating the ramp signal.
10. The signal generator according to claim 6, characterized in that, Each of the charge pump circuits includes: A first capacitor; A first switch, wherein a first end of the first switch receives a basic voltage, and a second end of the first switch is coupled to a first end of the first capacitor; A second switch, wherein a first end of the second switch is coupled to the first end of the first capacitor, and a second end of the second switch receives a ground voltage; A third switch, wherein a first end of the third switch receives the ground voltage, and a second end of the third switch is coupled to a second end of the first capacitor; A second capacitor, wherein a first end of the second capacitor is coupled to the second end of the first capacitor and generates the negative voltage, and a second end of the second capacitor receives the ground voltage; and A fourth switch, wherein a first end of the fourth switch is coupled to the second end of the first capacitor, and a second end of the fourth switch is coupled to the first end of the second capacitor.
11. The signal generator according to claim 10, characterized in that, The second switch and the third switch are simultaneously turned on and the first capacitor is discharged.
12. The signal generator according to claim 11, wherein, In a first stage, the first switch and the third switch are simultaneously turned on to charge the first capacitor; in a second stage, the second switch and the fourth switch are turned on to enable charge sharing between the first capacitor and the second capacitor, so as to generate the negative voltage at the first end of the second capacitor.
13. The signal generator according to claim 1, characterized in that, The sensor generates first control data according to the load demand of the load, generates second control data according to the voltage value of the operating voltage, and the sensor transmits the first control data and the second data to the signal output stage circuit.