A negative voltage control circuit, a laser radar and a movable platform

Abstract

The utility model discloses a kind of negative voltage control circuit, laser radar and movable platform, wherein the circuit includes digital-analog converter module, negative voltage control circuit and negative voltage power supply chip, the digital-analog converter module is connected the negative voltage control circuit, the negative voltage control circuit is connected with the feedback pin of the negative voltage power supply chip, the negative voltage control circuit includes wilson current mirror module, the circuit output end of the wilson current mirror module is connected with the feedback pin of the negative voltage power supply chip.The utility model's negative voltage control circuit is set in negative voltage control circuit by wilson current mirror module, to utilize its constant-current source characteristic stability, load fluctuation has little effect on output current characteristics, realize high-precision control to negative voltage.

Description

Technical Field

[0001] This utility model relates to the field of voltage control circuit technology, and in particular to a negative voltage control circuit, a lidar, and a mobile platform. Background Technology

[0002] The core working mechanism of SPAD (Single Photon Avalanche Diode) used in current lidar systems is to put the PN junction in "Gegege mode" (a state higher than the breakdown voltage VBD) by applying a reverse bias voltage (negative voltage). In this state, the electron-hole pairs generated by a single photon trigger chain collision ionization under a strong electric field, forming an avalanche current, thus detecting the single photon. The reverse bias voltage must exceed the breakdown voltage (VBD), i.e., the operating voltage VOP (Operation Voltage) = VBD + VEX (VEX is the over bias voltage). The magnitude of the negative voltage directly affects the SPAD's photon detection efficiency (PDE) and avalanche gain. During this process, the negative voltage needs to be dynamically adjusted to address issues such as the drift of the SPAD's breakdown voltage VBD with temperature changes and timing jitter.

[0003] In existing technologies, a common-base / gate amplifier circuit is used to input current to the controller feedback pin (FB pin), and the negative voltage is regulated by changing the PWM duty cycle. However, these methods introduce a problem into the calculation formula for the injected current. V be / V gs Two parameters are affected by temperature, and thus by the injected current. Precise current injection cannot be achieved. A closed-loop control with a voltage sampling circuit is required to achieve precise negative voltage control. Utility Model Content

[0004] This utility model provides a negative voltage control circuit, a lidar, and a mobile platform to solve the problems of complex negative voltage control circuits and excessive external components in the prior art.

[0005] According to a first aspect of the present invention, a negative voltage control circuit is provided, comprising a digital-to-analog converter module, a negative voltage control circuit, and a negative voltage power supply chip. The digital-to-analog converter module is connected to the negative voltage control circuit, and the negative voltage control circuit is connected to the feedback pin of the negative voltage power supply chip. The negative voltage control circuit includes a Wilson current mirror module, and the circuit output terminal of the Wilson current mirror module is connected to the feedback pin of the negative voltage power supply chip.

[0006] The negative voltage control circuit of this invention utilizes the Wilson current mirror module set in the negative voltage control circuit to achieve high-precision control of the negative voltage by taking advantage of its stable constant current source characteristics and the fact that load fluctuations have minimal impact on the output current.

[0007] In some embodiments, the Wilson current mirror module includes a first transistor, a second transistor, and a third transistor, all of which are PNP transistors of the same type. The emitter of the first transistor is connected to the output of the digital-to-analog converter module, the base of the first transistor is connected to the base of the second transistor, and the collector of the first transistor is connected to a second resistor and grounded. The emitter of the second transistor is connected to the output of the digital-to-analog converter module, and the collector of the second transistor is connected to the emitter of the third transistor. The output of the digital-to-analog converter module is also connected to a first resistor and connected between the base of the first transistor and the base of the second transistor, while extending to the emitter of the third transistor. The base of the third transistor is connected between the collector of the first transistor and the second resistor, and the collector of the third transistor is connected to the feedback pin of the negative voltage power supply chip.

[0008] Therefore, by using this configuration, a Wilson current mirror can be built using a PNP transistor to input current to the FB pin of the negative voltage power supply chip, thereby controlling the output of the negative voltage power supply chip.

[0009] In some embodiments, the resistance value of the first resistor is set to half the resistance value of the second resistor. Therefore, by setting it up in this way, the effect of the Wilson current mirror can be completely eliminated. V be This allows for programmable control of negative voltages.

[0010] In some embodiments, the Wilson current mirror module further includes a fourth transistor, which is a PNP transistor of the same type as the first, second, and third transistors. The fourth transistor is disposed between the collector of the first transistor and the base of the third transistor. The emitter of the fourth transistor is connected to the collector of the first transistor, and the base of the fourth transistor is connected to the base of the third transistor. The collector of the fourth transistor is connected to the second resistor.

[0011] Therefore, by setting it up in this way, the current error caused by the base width modulation effect of the PNP transistor can be eliminated, thereby further improving the control accuracy of the negative voltage.

[0012] In some embodiments, the Wilson current mirror module includes a first transistor, a second transistor, and a third transistor, wherein the first transistor, the second transistor, and the third transistor are all P-type field-effect transistors of the same type. The source of the first transistor is connected to the output of the digital-to-analog converter module, the gate of the first transistor is connected to the gate of the second transistor, and the drain of the first transistor is connected to a second resistor and grounded. The source of the second transistor is connected to the output of the digital-to-analog converter module, and the drain of the second transistor is connected to the source of the third transistor. The output of the digital-to-analog converter module is also connected to a first resistor and between the gate of the first transistor and the gate of the second transistor, while extending to the source of the third transistor. The gate of the third transistor is connected between the drain of the first transistor and the second resistor, and the drain of the third transistor is connected to the feedback pin of the negative voltage power supply chip.

[0013] Therefore, by using this configuration, a Wilson current mirror can be built using a P-type field-effect transistor to input current to the FB pin of the negative voltage power supply chip, thereby controlling the output of the negative voltage power supply chip.

[0014] In some implementations, the resistance value of the first resistor is set to half the resistance value of the second resistor.

[0015] Therefore, by setting it up in this way, the effect of the Wilson current mirror can be completely eliminated. V gs This allows for programmable control of negative voltages.

[0016] In some embodiments, the Wilson current mirror module further includes a fourth transistor, which is a P-type field-effect transistor of the same type as the first, second, and third transistors. The fourth transistor is disposed between the drain of the first transistor and the gate of the third transistor. The source of the fourth transistor is connected to the drain of the first transistor, the gate of the fourth transistor is connected to the gate of the third transistor, and the drain of the fourth transistor is connected to the second resistor.

[0017] Therefore, by setting it up in this way, the current error caused by the channel length modulation effect of the P-type field-effect transistor can be eliminated, and the control accuracy of the negative voltage can be further improved.

[0018] In some embodiments, a first voltage divider resistor and a second voltage divider resistor are connected between the circuit output terminal and the feedback pin of the negative voltage control circuit and the negative voltage power supply chip. One end of the first voltage divider resistor is connected between the negative voltage control circuit and the feedback pin of the negative voltage power supply chip, and the other end is connected to the circuit output terminal. One end of the second voltage divider resistor is connected between the negative voltage control circuit and the feedback pin of the negative voltage power supply chip, and the other end is grounded.

[0019] According to a second aspect of the present invention, a lidar is provided, comprising the negative voltage control circuit described in the first aspect above.

[0020] According to a third aspect of the present invention, a mobile platform is provided, characterized in that it is equipped with the lidar described in the second aspect above. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a circuit block diagram of a negative voltage control circuit according to one embodiment of the present invention. Figure 2 This is a circuit diagram of the Wilson current mirror module, which is composed of a circuit formed by connecting transistors, in the negative voltage control circuit of one embodiment of this utility model. Figure 3 The circuit diagram shows the Wilson current mirror module, which is formed by a circuit connected by transistors, in the negative voltage control circuit of another embodiment of this utility model. Figure 4 This is a circuit diagram of the Wilson current mirror module, which is a circuit formed by connecting transistors, in the negative voltage control circuit of one embodiment of this utility model. Figure 5 This is a circuit diagram of a Wilson current mirror module, which is a circuit formed by connecting transistors, in a negative voltage control circuit according to another embodiment of this utility model.

[0023] Explanation of reference numerals in the attached diagram: 1. Digital-to-analog converter module; 2. Negative voltage control circuit; 21. Wilson current mirror module; 3. Negative voltage power supply chip. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0026] In the description of this application, it should be understood that the use of terms such as "center," "middle," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" to indicate orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings is solely for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Features defined with "first" and "second" are used to distinguish feature names and do not have special meanings. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0028] It should also be noted that, in this document, the terms "comprising" or "including" include not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The terminology used herein is generally that commonly used by those skilled in the art; in case of any discrepancy with commonly used terminology, the terminology used herein shall prevail.

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0030] The present invention will now be described in further detail with reference to the accompanying drawings.

[0031] Figure 1 The circuit composition of a negative voltage control circuit according to one embodiment of this utility model is schematically shown. (Refer to...) Figure 1 As shown, the negative voltage control circuit of this invention comprises a digital-to-analog converter module 1, a negative voltage control circuit 2, and a negative voltage power supply chip 3. The digital-to-analog converter module 1 is connected to the negative voltage control circuit 2, and the negative voltage control circuit 2 is connected to the feedback pin of the negative voltage power supply chip 3. The digital-to-analog converter module 1 is used to output analog signals. The negative voltage control circuit 2 includes a Wilson current mirror module 21, and the circuit output terminal of the Wilson current mirror module 21 is connected to the feedback pin of the negative voltage power supply chip 3.

[0032] Specifically, the Wilson current mirror module is a circuit structure commonly used in analog circuits and current mirror technology for current amplification, current measurement, and current source matching. Utilizing the stable constant current source characteristics of the Wilson current mirror and the minimal impact of load fluctuations on the output current, high-precision control of negative voltages can be achieved. Specifically, the Wilson current mirror module 21 in this embodiment can be configured according to relevant content in the prior art. In some possible implementations, the Wilson current mirror module 21 can be composed of a circuit formed by connecting transistors, a circuit formed by connecting transistors, or other configurations; this invention does not limit these configurations.

[0033] Reference Figure 2 As shown, in a Wilson current mirror module 21 composed of circuits formed by transistor connections, it may include a first transistor, a second transistor, and a third transistor (respectively...). Figure 2 (Q1, Q2, and Q3 in the original text). Specifically, the first, second, and third transistors are all PNP transistors of the same type. Figure 2In the illustrated embodiment, the emitter of the first transistor is connected to the output of the digital-to-analog converter module 1, the base of the first transistor is connected to the base of the second transistor, and the collector of the first transistor is connected to a second resistor R2 and grounded. The emitter of the second transistor is connected to the output of the digital-to-analog converter module 1, and the collector of the second transistor is connected to the emitter of the third transistor. The output of the digital-to-analog converter module 1 is also connected to a first resistor R1, which is connected between the bases of the first and second transistors and extends to the emitter of the third transistor. The base of the third transistor is connected between the collector of the first transistor and the second resistor R2, and the collector of the third transistor is connected to the feedback pin of the negative voltage power supply chip 3. This configuration forms the Wilson current mirror module 21. In this configuration, a Wilson current mirror can be effectively built using a PNP transistor to input current to the FB pin of the negative voltage power supply chip 3, thereby realizing the output of the negative voltage power supply chip 3.

[0034] In one of the above embodiments, as a possible implementation, the resistance value of the first resistor R1 can be set to half the resistance value of the second resistor R2. This arrangement can completely eliminate the Wilson current mirror effect. V be This allows for programmable control of negative pressure.

[0035] Specifically, in the above embodiment, the current I injected into the FB pin of the negative voltage power supply chip 3 can be calculated using the following formula: in, β This is the current amplification factor of the transistor (typically 60~200). I R2 Let R be the current flowing through resistor R2. Then the above equation can be simplified to: V DAC This refers to the voltage value output by the DAC module. V eb This is the forward conduction voltage from the emitter to the base diode in a PNP transistor.

[0036] The current injected into the FB pin of the negative voltage power supply chip 3 is: It can be seen that the current is only related to the voltage and resistance, realizing programmable control of negative voltage output.

[0037] Furthermore, in some possible embodiments, the Wilson current mirror module 21, which is composed of a circuit formed by interconnected transistors, may also include a fourth transistor. (See also...) Figure 3 As shown, the fourth transistor (i.e. Figure 5 Q4 in the transistor is a PNP transistor of the same type as the first, second, and third transistors. A fourth transistor is positioned between the collector of the first transistor and the base of the third transistor. The emitter of the fourth transistor is connected to the collector of the first transistor, and the base of the fourth transistor is connected to the base of the third transistor. The collector of the fourth transistor is connected to the second resistor R2. By adding a fourth transistor, the current error caused by the base width modulation effect of the PNP transistor can be further eliminated, thus further improving the control accuracy of the negative voltage.

[0038] Reference Figure 4 As shown, Figure 4 The circuit composition of the Wilson current mirror module 21, consisting of circuits formed by transistor connections, is further illustrated. Specifically, in Figure 4 In the illustrated embodiment, the Wilson current mirror module 21 includes a first transistor, a second transistor, and a third transistor (i.e., Figure 4 (Q1, Q2, Q3 in the diagram). The first, second, and third transistors are all P-type field-effect transistors of the same model. The source of the first transistor is connected to the output of the digital-to-analog converter module 1, the gate of the first transistor is connected to the gate of the second transistor, and the drain of the first transistor is connected to a second resistor R2 and grounded. The source of the second transistor is connected to the output of the digital-to-analog converter module 1, and the drain of the second transistor is connected to the source of the third transistor. The output of the digital-to-analog converter module 1 is also connected to a first resistor and connected between the gates of the first and second transistors, extending to the source of the third transistor. The gate of the third transistor is connected between the drain of the first transistor and the second resistor R2, and the drain of the third transistor is connected to the feedback pin of the negative voltage power supply chip 3. This configuration forms the Wilson current mirror module 21. In this configuration, the P-type field-effect transistors can be used to form a Wilson current mirror to input current to the FB pin of the negative voltage power supply chip 3, thereby realizing the output of the negative voltage power supply chip 3.

[0039] In the above embodiments, as some possible implementations, the resistance value of the first resistor R1 can also be set to half the resistance value of the second resistor R2. This arrangement can completely eliminate the Wilson current mirror effect. V gs This allows for programmable control of negative pressure.

[0040] Specifically, in the above embodiment, the current I injected into the FB pin of the negative voltage power supply chip 3 can be calculated using the following formula: V DAC This refers to the voltage value output by the DAC module. V gs This is the gate-source voltage of a P-type field-effect transistor.

[0041] The current injected into the FB pin of the negative voltage power supply chip 3 is: It can be seen that the current is only related to the voltage and resistance, realizing programmable control of negative voltage output.

[0042] Furthermore, in some possible embodiments, the Wilson current mirror module 21, which is composed of a circuit formed by transistor connections, may also include a fourth transistor. (See also...) Figure 5 As shown, the fourth transistor (i.e. Figure 5 Q4 in the transistor is a P-type field-effect transistor, the same type as the first, second, and third transistors. The fourth transistor is positioned between the drain of the first transistor and the gate of the third transistor. The source of the fourth transistor is connected to the drain of the first transistor, and its gate is connected to the gate of the third transistor. The drain of the fourth transistor is connected to the second resistor R2. By adding this fourth transistor, the current error caused by the channel length modulation effect of the P-type field-effect transistor can be further eliminated, thus further improving the control accuracy of the negative voltage.

[0043] Reference Figures 2 to 5 As shown, a first voltage divider resistor R is also connected between the circuit output terminal of the Wilson current mirror module 21 and the feedback pin of the negative voltage control circuit 2 and the negative voltage power supply chip 3. FBT Second voltage divider resistor R FBB The first voltage divider resistor R FBT One end is connected between the feedback pin of the negative pressure control circuit 2 and the negative pressure power supply chip 3, and the other end is connected to the circuit output terminal V. -out The second voltage divider resistor R FBB One end is connected between the feedback pin of the negative pressure control circuit 2 and the negative pressure power supply chip 3, and the other end is grounded.

[0044] The negative voltage control circuit of this invention utilizes the Wilson current mirror module 21 within the negative voltage control circuit 2. This module leverages the stable constant current source characteristics and the minimal impact of load fluctuations on the output current to achieve high-precision control of the negative voltage. Simultaneously, it reduces the number of external components, thereby lowering cost and size.

[0045] This invention also provides an electronic device equipped with a negative voltage control circuit according to any of the above-described embodiments, thereby enabling the electronic device to reduce external components, lower costs and size, and achieve programmable negative voltage output.

[0046] This utility model also provides a lidar, which is equipped with a negative voltage control circuit according to any of the above-described embodiments, thereby enabling the lidar to reduce external components, lower cost and size, achieve programmable negative voltage output, and improve reliability.

[0047] This utility model also provides a mobile platform, wherein the aforementioned lidar is installed on the mobile platform. The mobile platform described in this utility model embodiment can be, for example, a mobile robot, model aircraft, drone, robotic arm, car, ship, etc. It should also be noted that the structure of the mobile platform is not limited to this; this embodiment is merely illustrative.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A negative voltage control circuit, characterized in that, The device includes a digital-to-analog converter module, a negative pressure control circuit, and a negative pressure power supply chip. The digital-to-analog converter module is connected to the negative pressure control circuit, and the negative pressure control circuit is connected to the feedback pin of the negative pressure power supply chip. The negative pressure control circuit includes a Wilson current mirror module, and the circuit output terminal of the Wilson current mirror module is connected to the feedback pin of the negative pressure power supply chip.

2. The negative voltage control circuit according to claim 1, characterized in that, The Wilson current mirror module includes a first transistor, a second transistor, and a third transistor, all of which are PNP transistors of the same type. The emitter of the first transistor is connected to the output of the digital-to-analog converter module, the base of the first transistor is connected to the base of the second transistor, and the collector of the first transistor is connected to a second resistor and grounded. The emitter of the second transistor is connected to the output of the digital-to-analog converter module, and the collector of the second transistor is connected to the emitter of the third transistor. The output of the digital-to-analog converter module is also connected to a first resistor and connected between the base of the first transistor and the base of the second transistor, while extending to the emitter of the third transistor. The base of the third transistor is connected between the collector of the first transistor and the second resistor, and the collector of the third transistor is connected to the feedback pin of the negative voltage power supply chip.

3. The negative voltage control circuit according to claim 2, characterized in that, The resistance value of the first resistor is set to half the resistance value of the second resistor.

4. The negative voltage control circuit according to claim 2, characterized in that, The Wilson current mirror module also includes a fourth transistor, which is the same type of PNP transistor as the first, second, and third transistors. The fourth transistor is disposed between the collector of the first transistor and the base of the third transistor. The emitter of the fourth transistor is connected to the collector of the first transistor, and the base of the fourth transistor is connected to the base of the third transistor. The collector of the fourth transistor is connected to the second resistor.

5. The negative voltage control circuit according to claim 1, characterized in that, The Wilson current mirror module includes a first transistor, a second transistor, and a third transistor, all of which are P-type field-effect transistors of the same type. The source of the first transistor is connected to the output of the digital-to-analog converter module, the gate of the first transistor is connected to the gate of the second transistor, and the drain of the first transistor is connected to a second resistor and grounded. The source of the second transistor is connected to the output of the digital-to-analog converter module, and the drain of the second transistor is connected to the source of the third transistor. The output of the digital-to-analog converter module is also connected to a first resistor and between the gate of the first transistor and the gate of the second transistor, while extending to the source of the third transistor. The gate of the third transistor is connected between the drain of the first transistor and the second resistor, and the drain of the third transistor is connected to the feedback pin of the negative voltage power supply chip.

6. The negative voltage control circuit according to claim 5, characterized in that, The resistance value of the first resistor is set to half the resistance value of the second resistor.

7. The negative voltage control circuit according to claim 5, characterized in that, The Wilson current mirror module also includes a fourth transistor, which is a P-type field-effect transistor of the same type as the first, second, and third transistors. The fourth transistor is disposed between the drain of the first transistor and the gate of the third transistor. The source of the fourth transistor is connected to the drain of the first transistor, the gate of the fourth transistor is connected to the gate of the third transistor, and the drain of the fourth transistor is connected to the second resistor.

8. The negative voltage control circuit according to any one of claims 1 to 7, characterized in that, A first voltage divider resistor and a second voltage divider resistor are connected between the output terminal of the circuit and the feedback pin of the negative voltage control circuit and the negative voltage power supply chip. One end of the first voltage divider resistor is connected between the negative voltage control circuit and the feedback pin of the negative voltage power supply chip, and the other end is connected to the output terminal of the circuit. One end of the second voltage divider resistor is connected between the negative voltage control circuit and the feedback pin of the negative voltage power supply chip, and the other end is grounded.

9. A lidar, characterized in that, Includes the negative voltage control circuit described in any one of claims 1 to 8.

10. A mobile platform, characterized in that, The device is equipped with the lidar described in claim 9.

Images