Double-voltage power supply circuit and method applied to laser radar

Abstract

The invention provides a double-voltage power supply circuit and method applied to a laser radar. The circuit comprises four parts, namely a processor, a voltage conversion module, a switching power supply and a laser transmitter. Wherein the processor is mainly used for controlling high and low voltages and providing periodic PWM (Pulse Width Modulation) signals; the voltage conversion module is used for converting the PWM signal into an analog signal; the power supply feedback network outputs a corresponding output voltage according to the analog signal; and the laser transmitter transmits a corresponding laser signal according to the output voltage. The method comprises the following steps: generating a periodic PWM signal; converting the PWM signal into an analog signal; generating a corresponding output voltage according to the analog signal; and transmitting a corresponding laser signal according to the output voltage. According to the invention, the output of two voltages can be effectively realized by a single power supply in the aspect of laser radar application, automatic high-frequency output voltage switching can be realized, and the requirement that the switching time of the two voltages must be controlled at a microsecond level is met.

Description

Technical Field

[0001] The present application relates to the field of laser radar technology, and in particular to a dual-voltage power supply circuit and method for laser radar application. Background Art

[0002] With the growing development of intelligent driving technology, the importance of laser radar (LiDAR) in the field of vehicle technology is growing, especially in autonomous driving and intelligent transportation systems. When the current on-board one-dimensional rotating mirror laser radar emits lasers, it will emit two levels of power in a short time of microseconds. The high-power laser is used to detect objects at a distance, and the low-power laser is used to judge nearby objects and reduce the amount of light reflected by objects with high reflectivity, so as to achieve the optimal point cloud effect. In the prior art, different transmission powers are given to the laser by outputting two voltages. This method uses an extra power supply, so the cost is relatively high. Since each point cloud needs to emit two laser powers for detection, the switching time of the two voltages must be controlled at the microsecond level. Summary of the invention

[0003] To solve the above technical problems, the present application provides a dual-voltage power supply circuit and method for laser radar applications, adds a voltage conversion module, reuses the existing processor and power feedback network on the laser radar system, and can realize automatic high-frequency output voltage switching.

[0004] In a first aspect, the present application provides a dual voltage power supply circuit for laser radar application, specifically comprising:

[0005] Processor, voltage conversion module, switching power supply and laser transmitter;

[0006] The processor transmits high and low voltage control signals to the switching power supply; the processor transmits a PWM signal to the voltage conversion module; the voltage conversion module converts the PWM signal into an analog signal and outputs it to the switching power supply; the switching power supply outputs a corresponding output voltage to the laser emitter according to the analog signal; the laser emitter emits a corresponding laser signal according to the output voltage.

[0007] Wherein, the voltage conversion module includes: an RC network and an operational amplifier or a voltage follower.

[0008] The processor transmits high and low voltage control signals for preliminarily adjusting the output range of the output voltage of the switching power supply.

[0009] The processor transmits a PWM signal, which is a modulation technique that controls power output by changing the pulse width of the signal. This technique is widely used in motor control, LED dimming, audio signal generation and other fields, and has a duty cycle, which refers to the ratio of the time the signal is high to the total cycle time in one cycle. It is usually expressed as a percentage, for example, a duty cycle of 50% means that the signal is high for half of the time in one cycle and low for the other half of the time. Due to the characteristics of the PWM signal, it can meet the requirements of some circuits that need to frequently switch between high and low levels.

[0010] As a preferred embodiment, after receiving the PWM signal transmitted by the processor, the RC network converts the signal into an initial analog signal and sends it to the operational amplifier or voltage follower.

[0011] After receiving the initial analog signal, the operational amplifier or voltage follower outputs an analog signal to the power feedback network.

[0012] The RC network is a common circuit configuration, mainly composed of resistors and capacitors. It plays an important role in applications such as signal processing, filtering, time delay, etc. In terms of application, it can include signal processing, oscillator and clock circuits or power management. In this solution, it is mainly used to convert the PWM signal into the initial analog signal.

[0013] An operational amplifier is a high-gain electronic amplifier with two inputs (inverting and non-inverting) and one output. It can perform various mathematical operations such as addition, subtraction, integration and differentiation, and is often used in adders and subtractors, integrators and differentiators, signal amplifiers or filters and comparators.

[0014] A voltage follower is a specifically configured operational amplifier circuit, typically used to pass the input voltage directly to the output without gain amplification, for signal buffering and impedance matching.

[0015] The operational amplifier or voltage follower is used to amplify the initial analog signal or keep the initial analog signal as an analog signal to provide a suitable analog signal for the power feedback network.

[0016] Preferably, the switching power supply comprises: a power supply, a switching unit and a feedback network; the switching unit and the feedback network are embedded in the power supply.

[0017] The switch unit receives the high and low voltage control signals and is used to quickly switch the output voltage of the switching power supply.

[0018] The feedback network receives the analog signal and is used to control the output voltage of the power supply according to the analog signal.

[0019] Preferably, the feedback network includes: a first voltage dividing unit, a second voltage dividing unit and a third voltage dividing unit.

[0020] The voltage dividing unit includes: a first voltage dividing unit, a second voltage dividing unit and a third voltage dividing unit.

[0021] The first voltage dividing unit, the second voltage dividing unit and the third voltage dividing unit are connected to a node VFB;

[0022] The first voltage dividing unit is also connected to the switching power supply.

[0023] The second voltage dividing unit is connected to the switch unit.

[0024] The third voltage dividing unit is also connected to the operational amplifier or the voltage follower.

[0025] Laser transmitters typically control their output power by adjusting the input voltage. The higher the input voltage, the greater the current in the laser diode (or other laser source), resulting in a stronger laser output.

[0026] Preferably, the second voltage dividing unit includes: a first sub-voltage dividing unit and a second sub-voltage dividing unit; the first sub-voltage dividing unit and the second sub-voltage dividing unit are connected in parallel, and the first sub-voltage dividing unit is connected to the switch unit.

[0027] The switch unit is controlled by the high and low levels of the processor output, and the switch unit also controls whether the second sub-voltage divider unit is turned on or off. If it is turned on, the second sub-voltage divider unit participates in the voltage division of the voltage divider unit, and if it is turned off, the second sub-voltage divider unit does not participate in the voltage division of the voltage divider unit. Due to this method design, the output voltage of the switching power supply can be quickly switched over a large range, effectively realizing automatic high-frequency output voltage switching.

[0028] In a second aspect, the present application proposes a method for a dual voltage power supply circuit for a laser radar application, the method comprising:

[0029] S1: Output level signal according to required voltage.

[0030] S2: Generate an initial output voltage according to the level signal.

[0031] S3: Generate a periodic PWM signal.

[0032] S4: Convert the PWM signal into an initial analog signal.

[0033] S5: Convert the initial analog signal into an analog signal.

[0034] S6: According to the analog signal, the initial output voltage is adjusted to obtain an output voltage.

[0035] S7: emitting a corresponding laser signal according to the output voltage.

[0036] The PWM signal is emitted by the processor. The PWM signal is a modulation technology that controls the power output by changing the pulse width of the signal. This technology is widely used in motor control, LED dimming, audio signal generation and other fields. It has a duty cycle, which refers to the ratio of the time the signal is high to the total cycle time in one cycle. It is usually expressed as a percentage. For example, a duty cycle of 50% means that the signal is high for half of the time in one cycle and low for the other half of the time. Due to the characteristics of the PWM signal, it can meet the requirements of some circuits that need to frequently switch between high and low levels.

[0037] Preferably, the step S1 specifically comprises:

[0038] When the processor outputs a high level signal, the initial output voltage generated by the switching power supply is a high voltage.

[0039] When the processor outputs a low level signal, the initial output voltage generated by the switching power supply is a low voltage.

[0040] When the processor outputs a high-level signal, the voltage division situation in the voltage division unit is as follows: the second voltage division unit divides the voltage with the third voltage division unit, and then divides the voltage with the first voltage division unit. At this time, the voltage divided by the first voltage division unit is higher, and the output voltage is equal to the voltage of the first voltage division unit, so a high output voltage is generated.

[0041] When the processor outputs a low level signal, the voltage division situation in the voltage division unit is: the first voltage division unit and the second voltage division unit divide the voltage. At this time, the voltage divided by the first voltage division unit is lower, and the output voltage is equal to the voltage of the first voltage division unit, so a low output voltage is generated.

[0042] Preferably, the step S5 is specifically as follows:

[0043] When the output voltage is a high output voltage, a high-power laser signal is emitted.

[0044] When the output voltage is a low output voltage, a low-power laser signal is emitted.

[0045] Laser transmitters typically control their output power by adjusting the input voltage. The higher the input voltage, the greater the current in the laser diode (or other laser source), resulting in a stronger laser output.

[0046] In summary, the present application proposes a dual voltage power supply circuit and method for laser radar application, wherein the circuit includes four parts: a processor, a voltage conversion module, a switching power supply and a laser transmitter. Among them, the processor is mainly used to control high and low voltages and provide a periodic PWM signal; the voltage conversion module is used to convert the PWM signal into an analog signal; the power supply feedback network outputs a corresponding output voltage according to the analog signal; and the laser transmitter emits a corresponding laser signal according to the output voltage. The method includes: generating a periodic PWM signal; converting the PWM signal into an analog signal; generating a corresponding output voltage according to the analog signal; and emitting a corresponding laser signal according to the output voltage.

[0047] Compared with the prior art, this application has at least the following beneficial effects:

[0048] The present application can effectively realize the output of two voltages with a single power supply in lidar applications, and can realize automatic high-frequency switching of the output voltages, meeting the requirement that the switching time of the two voltages must be controlled at the microsecond level. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of the dual-voltage power supply circuit structure of the laser radar application shown in the embodiment of the present application.

[0050] Figure 2 It is a schematic diagram of the feedback network structure shown in an embodiment of the present application.

[0051] Figure 3 This is a flow chart of a dual voltage power supply method for laser radar application shown in an embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the present application, the following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only

[0053] The embodiments of this application are part of the embodiments, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0054] The following are detailed descriptions of each.

[0055] The terms "first", "second", "third" and "third" in the specification and claims of this application and the drawings are used interchangeably.

[0056] "four" and the like are used to distinguish different objects rather than to describe a specific order. In addition, the term "comprise" and any variation thereof are intended to cover non-exclusive inclusions. For example, a system including a series of modules and devices is not limited to the listed modules and devices, but may optionally include modules and devices that are not listed, or may optionally include other modules and devices that are inherent to these systems.

[0057] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0058] Embodiment 1:

[0059] As attached Figure 1 As shown, the present application provides a dual voltage power supply circuit for laser radar application, specifically including:

[0060] Processor, voltage conversion module, switching power supply and laser transmitter.

[0061] The processor transmits high and low voltage control signals to the switching power supply; the processor transmits a PWM signal to the voltage conversion module; the voltage conversion module converts the PWM signal into an analog signal and outputs it to the switching power supply; the switching power supply outputs a corresponding output voltage to the laser emitter according to the analog signal; the laser emitter emits a corresponding laser signal according to the output voltage.

[0062] The processor transmits a PWM signal, which is a modulation technique that controls power output by changing the pulse width of the signal. This technique is widely used in motor control, LED dimming, audio signal generation and other fields, and has a duty cycle, which refers to the ratio of the time the signal is high to the total cycle time in one cycle. It is usually expressed as a percentage, for example, a duty cycle of 50% means that the signal is high for half of the time in one cycle and low for the other half of the time. Due to the characteristics of the PWM signal, it can meet the requirements of some circuits that need to frequently switch between high and low levels.

[0063] The processor may be any processor capable of transmitting a PWM signal, such as:

[0064] Microcontroller (MCU), many microcontrollers have built-in PWM functions, which can easily generate PWM signals. Common microcontrollers include:

[0065] Arduino series: such as Arduino Uno, supports multi-channel PWM output.

[0066] PIC Series: Microchip's PIC microcontrollers usually have a built-in PWM module.

[0067] AVR series: such as ATmega series, supports multiple PWM modes.

[0068] STM32 Series: STMicroelectronics' STM32 series microcontrollers also provide powerful PWM functions.

[0069] S32K Series: NXP's S32K series MCU has powerful PWM functions for automotive applications.

[0070] DSPs are often used in applications that require complex signal processing, and many DSPs can also generate PWM signals. For example:

[0071] Texas Instruments' TMS320 series: suitable for real-time signal processing and capable of generating PWM waveforms.

[0072] FPGA allows users to customize logic circuits and design flexible PWM generation modules for high-performance or multi-channel PWM applications.

[0073] In some applications, ASICs designed specifically for PWM generation may be used; these chips typically excel in terms of high efficiency and high integration.

[0074] In an embodiment of the present invention, optionally, the processor used in the embodiment of the present application is a microcontroller of the S32K series, and a code file is set in the microcontroller for periodically generating a PWM signal.

[0075] Preferably, the voltage conversion module includes: an RC network and an operational amplifier or a voltage follower.

[0076] After receiving the PWM signal transmitted by the processor, the RC network converts the signal into an initial analog signal and sends it to the operational amplifier or voltage follower.

[0077] After receiving the initial analog signal, the operational amplifier or voltage follower outputs an analog signal to the power feedback network.

[0078] The RC network is a common circuit configuration that consists mainly of resistors and capacitors. It plays an important role in applications such as signal processing, filtering, time delay, etc. The applications can include signal processing, oscillator and clock circuits or power management.

[0079] There are several types of RC networks:

[0080] Low-pass filter: A resistor and a capacitor are connected in series, and the output is taken from both ends of the capacitor. It allows low-frequency signals to pass through and attenuates high-frequency signals. It is used in audio processing and noise removal circuits.

[0081] High-pass filter: capacitor and resistor are connected in series, and the output is taken from both ends of the resistor. It allows high-frequency signals to pass through and attenuates low-frequency signals. It is used in audio signal processing and fast signal detection.

[0082] Integrator: The input signal passes through a resistor, the capacitor is connected to the ground, and the output is taken from both ends of the capacitor. The input signal is integrated, and the output voltage increases with time. It is used in analog computers and signal processing.

[0083] Differentiator: A capacitor is connected in series with a resistor, and the output is taken from both ends of the resistor. The input signal is differentiated, and the output voltage is proportional to the rate of change of the input signal. It is used for edge detection and monitoring of signal change rate.

[0084] The transmission characteristics of the RC network include: Time constant (τ): τ = R × C, which indicates the speed of the circuit response. The larger τ is, the slower the circuit responds. Cut-off frequency (fc): For filter design, the cut-off frequency fc = 1 / (2πRC), marking the frequency point where the signal strength decreases to a certain level.

[0085] In an embodiment of the invention, optionally, the RC network used is an integrator, which is mainly used to convert the PWM signal into an initial analog signal.

[0086] An operational amplifier is a high-gain electronic amplifier with two inputs (inverting and non-inverting) and one output. It can perform various mathematical operations such as addition, subtraction, integration and differentiation, and is often used in adders and subtractors, integrators and differentiators, signal amplifiers or filters and comparators.

[0087] Operational amplifiers have the following characteristics:

[0088] High Gain: An ideal op amp has a very high gain.

[0089] Differential input: Only the voltage difference between the two input terminals is amplified.

[0090] High input impedance: Ideally, the input impedance is infinite, effectively reducing the load on the previous circuit.

[0091] Low output impedance: convenient for driving subsequent circuits.

[0092] A voltage follower is a specifically configured operational amplifier circuit, typically used to pass the input voltage directly to the output without gain amplification, for signal buffering and impedance matching.

[0093] The voltage follower has the following characteristics:

[0094] High input impedance: hardly affects the operation of the previous stage circuit.

[0095] Low output impedance: capable of driving lower impedance loads.

[0096] Unity Gain: The output voltage is equal to the input voltage.

[0097] The operational amplifier or voltage follower is used to amplify the initial analog signal or keep the initial analog signal as an analog signal to provide a suitable analog signal for the power feedback network.

[0098] In the embodiment of the present invention, optionally, an operational amplifier or a voltage follower is selected considering the actual analog signal requirement.

[0099] In an embodiment of the present invention, optionally, the MCU outputs a high-precision PWM signal, which forms a corresponding analog voltage after passing through the RC network. The analog voltage is output to the power feedback network through a voltage follower to adjust the power supply voltage output. The PWM precision step can be set to 0.1%, and the output voltage will be adjusted accordingly by 0.1%, which can basically achieve stepless adjustment. The voltage follower or operational amplifier increases the driving capability of the output analog voltage.

[0100] Preferably, the switching power supply comprises: a power supply, a switching unit and a feedback network; the switching unit and the feedback network are embedded in the power supply.

[0101] The switch unit receives the high and low voltage control signals and is used to quickly switch the output voltage of the switching power supply.

[0102] The feedback network receives the analog signal and is used to control the output voltage of the power supply according to the analog signal.

[0103] Preferably, the feedback network includes: a first voltage dividing unit, a second voltage dividing unit and a third voltage dividing unit.

[0104] The first voltage dividing unit, the second voltage dividing unit and the third voltage dividing unit are connected to a node VFB.

[0105] The first voltage dividing unit is also connected to the output voltage terminal of the feedback network.

[0106] The third voltage dividing unit is also connected to the switch unit.

[0107] Preferably, the node VFB is connected to the power supply.

[0108] The switching unit is controlled by the high and low levels of the processor. The switching unit simultaneously controls the conduction or non - conduction of the third voltage - dividing unit. If it is conductive, the third voltage - dividing unit participates in the voltage division of the voltage - dividing unit. If it is cutoff, the third voltage - dividing unit does not participate in the voltage division of the voltage - dividing unit. Due to this method design, it is possible to achieve periodic control of the power supply feedback network to output high voltage or low voltage by the PWM signal, and it can effectively achieve automatic and high - frequency switching of the output voltage.

[0109] As shown in the appendix Figure 2 As shown, it is a schematic diagram of the power supply feedback network structure shown in the embodiments of the present application. It can be seen from the figure that in the embodiments of the present invention, optionally, the power supply is provided with a stable reference voltage by a DCDC internal voltage - stabilizing source. In other embodiments, it can also be a DC power supply formed after rectifying the current generated by an alternator, a power battery or a storage battery.

[0110] The switching unit is composed of a switching MOS transistor Q1. The MOS (metal - oxide - semiconductor) transistor is a widely used field - effect transistor, and its conduction characteristic is the key to its working performance. There are mainly two types of MOS transistors: N - channel MOSFET and P - channel MOSFET. Their conduction characteristics are slightly different, but the basic principle is similar.

[0111] Threshold voltage (Vth): The key parameter for the MOSFET to conduct. Only when the gate voltage (Vgs) exceeds the threshold voltage will the MOSFET conduct.

[0112] For an N - channel MOSFET, it conducts when Vgs > Vth.

[0113] For a P - channel MOSFET, it conducts when Vgs < Vth.

[0114] The gate of the switching MOS transistor Q1 is connected to the output terminal of the voltage - conversion circuit and is controlled by the output voltage of the voltage - conversion circuit to conduct or not.

[0115] It can be seen from the figure that in the embodiments of the present invention, optionally, the first voltage - dividing unit, the second voltage - dividing unit and the third voltage - dividing unit are all composed of resistors. Specifically: the first voltage - dividing unit: R1, the second voltage - dividing unit: R2, and the third voltage - dividing unit: R3.

[0116] Resistor voltage division is a commonly used principle in circuits. It realizes the required voltage output by distributing the voltage among multiple resistors.

[0117] The basic principle of resistor voltage division is based on Ohm's law (V = IR), that is, voltage (V) equals current (I) multiplied by resistance (R). When multiple resistors are connected in series, the input voltage will be distributed among these resistors according to their resistance values.

[0118] It can be seen from the figure that in the embodiment of the present invention, optionally, the feedback network includes a peripheral circuit in addition to the voltage divider unit.

[0119] In the embodiment of the present invention, optionally, the peripheral circuit includes: a capacitor C1, a capacitor C2 and an inductor L1.

[0120] Capacitance refers to the ability of a component to store charge. Its unit is farad (F). Usually in practical applications, capacitors with smaller capacitance values ​​are expressed in microfarad (μF), nanofarad (nF) or picofarad (pF).

[0121] Capacitors are usually made of two conductors (called plates) and an insulating material (called the dielectric). The type of dielectric affects the performance of the capacitor.

[0122] Capacitors are commonly used in: filters, used to smooth voltage fluctuations and reduce noise in power circuits; coupling and decoupling, used to isolate DC signals from AC signals in amplifier circuits; timing circuits, in oscillators and timers, capacitors are used in combination with resistors to form timing elements; energy storage devices, in some applications, such as flashlights, capacitors are used to quickly release large amounts of electricity.

[0123] Inductance refers to the ability of a component to respond to changes in current, and its unit is Henry (H). The larger the inductance value, the stronger its resistance to current changes.

[0124] Inductors are usually made of a wire wound into a coil. The shape and winding method of the coil will affect the size of the inductance.

[0125] Inductors are often used in filters to eliminate unnecessary high-frequency signals and smooth power output; in oscillators, they are used in conjunction with capacitors in oscillation circuits to form LC oscillators; in transformers, they use the principle of mutual inductance to achieve voltage conversion; in power management, they are used to store and release energy in switching power supplies and DC-DC converters.

[0126] In the embodiment of the present invention, the inductor L1 is optionally an energy storage inductor used in a switching power supply, the capacitor C1 is a filter capacitor used to stabilize the voltage of Vout, and the capacitor C2 is used to filter out jitter errors during voltage switching.

[0127] In the embodiment of the present invention, optionally, as shown in the attached Figure 2 As shown, the connection relationship between the various modules and devices of the feedback network shown in the embodiment of the present application is as follows:

[0128] The base of the switch MOS tube Q1 is connected to the output end of the processor, the emitter of the switch MOS tube Q1 is grounded, the collector of the switch MOS tube Q1 is connected to one end of the third voltage-dividing resistor R3, and the other end of the third voltage-dividing resistor R3 is connected to the node VFB.

[0129] One end of the second voltage-dividing resistor R2 is connected to the node VFB, and the other end of the second voltage-dividing resistor R2 is grounded.

[0130] One end of the capacitor C2 is connected to the node VFB, and the other end of the capacitor C2 is grounded.

[0131] One end of the first voltage-dividing resistor R1 is connected to the node VFB, and the other end of the first voltage-dividing resistor R1 is connected to the output voltage end of the feedback network.

[0132] One end of the fourth voltage-dividing resistor R4 is connected to the node VFB, and the other end is connected to the voltage follower.

[0133] One end of the inductor L1 is connected to the power supply, and the other end is connected to the output voltage end of the feedback network.

[0134] One end of the capacitor C1 is connected to the output voltage end of the feedback network, and the other end is grounded.

[0135] In the embodiment of the present invention, optionally, the working principle of the feedback network is as follows:

[0136] The switch MOS tube Q1 is used as a signal switching switch, and its on-resistance is at the milliohm level, which is much smaller than the first voltage-dividing resistor R1. The processor MCU controls the on and off of the switch MOS tube Q1 through the control signal. When the switch MOS tube Q1 is turned off, the output voltage of VOUT is only related to the resistance values ​​of R1 and R2. When the switch MOS tube Q1 is turned on, the resistance value of the lower resistor of VFB is obtained by connecting R2 and R3 in parallel, which can be defined as Rx. The resistance value of Rx is R1*R2 / (R1+R2). At this time, the output voltage of VOUT is VOUT=VFB / Rx*(R1+Rx). Through this design method, the processor MCU can automatically switch the resistance value to realize the two voltage outputs of VOUT. The resistance value of R3 is more than 10 times smaller than that of R2. When the control signal is switched, Vout can be switched over a wide range. The resistance value of R4 is between R2 and R3. The MCU outputs a high-precision PWM signal, which forms a corresponding analog voltage after passing through the RC network. The analog voltage is output to the power feedback network through the voltage follower to adjust the power supply voltage output. The PWM precision step can be set to 0.1%, and the output voltage will be adjusted accordingly by 0.1%, which can basically achieve stepless adjustment. The purpose of the voltage follower is to increase the driving capability of the output analog voltage.

[0137] The voltage output by the voltage follower is assumed to be Vin, which is determined by the duty cycle of the previous PWM. When the duty cycle is 100%, Vin is 3.3V, and when the duty cycle is 0%, Vin is 0V. The intermediate value PWM and Vin voltage are linearly changing, which can be calculated based on

[0138]

[0139] Kirchhoff's current law calculates the voltage of Vout:

[0140] Preferably, the output voltage end of the feedback network is connected to the laser emitter.

[0141] Laser transmitters typically control their output power by adjusting the input voltage. The higher the input voltage, the greater the current in the laser diode (or other laser source), resulting in a stronger laser output.

[0142] Embodiment 2:

[0143] The present application proposes a method for a dual voltage power supply circuit for laser radar application, the method comprising:

[0144] S1: Output level signal according to required voltage.

[0145] S2: Generate an initial output voltage according to the level signal.

[0146] S3: Generate a periodic PWM signal.

[0147] S4: Convert the PWM signal into an initial analog signal.

[0148] S5: Convert the initial analog signal into an analog signal.

[0149] S6: According to the analog signal, the initial output voltage is adjusted to obtain an output voltage.

[0150] S7: emitting a corresponding laser signal according to the output voltage.

[0151] The PWM signal is emitted by the processor. The PWM signal is a modulation technology that controls the power output by changing the pulse width of the signal. This technology is widely used in motor control, LED dimming, audio signal generation and other fields. It has a duty cycle, which refers to the ratio of the time the signal is high to the total cycle time in one cycle. It is usually expressed as a percentage. For example, a duty cycle of 50% means that the signal is high for half of the time in one cycle and low for the other half of the time. Due to the characteristics of the PWM signal, it can meet the requirements of some circuits that need to frequently switch between high and low levels.

[0152] Preferably, the step S1 specifically comprises:

[0153] When the processor outputs a high level signal, the initial output voltage generated by the switching power supply is a high voltage.

[0154] When the processor outputs a low level signal, the initial output voltage generated by the switching power supply is a low voltage.

[0155] When the processor outputs a high-level signal, the voltage division situation in the voltage division unit is as follows: the second voltage division unit divides the voltage with the third voltage division unit, and then divides the voltage with the first voltage division unit. At this time, the voltage divided by the first voltage division unit is higher, and the output voltage is equal to the voltage of the first voltage division unit, so a high output voltage is generated.

[0156] When the processor outputs a low level signal, the voltage division situation in the voltage division unit is: the first voltage division unit and the second voltage division unit divide the voltage. At this time, the voltage divided by the first voltage division unit is lower, and the output voltage is equal to the voltage of the first voltage division unit, so a low output voltage is generated.

[0157] Preferably, the step S5 is specifically:

[0158] When the output voltage is a high output voltage, a high-power laser signal is emitted.

[0159] When the output voltage is a low output voltage, a low-power laser signal is emitted.

[0160] Laser transmitters typically control their output power by adjusting the input voltage. The higher the input voltage, the greater the current in the laser diode (or other laser source), resulting in a stronger laser output.

[0161] In summary, the present application proposes a dual voltage power supply circuit and method for laser radar application, wherein the circuit includes four parts: a processor, a voltage conversion module, a switching power supply and a laser transmitter. Among them, the processor is mainly used to control high and low voltages and provide a periodic PWM signal; the voltage conversion module is used to convert the PWM signal into an analog signal; the power supply feedback network outputs a corresponding output voltage according to the analog signal; and the laser transmitter emits a corresponding laser signal according to the output voltage. The method includes: generating a periodic PWM signal; converting the PWM signal into an analog signal; generating a corresponding output voltage according to the analog signal; and emitting a corresponding laser signal according to the output voltage.

[0162] The present application can effectively realize the output of two voltages with a single power supply in lidar applications, and can realize automatic high-frequency switching of the output voltages, meeting the requirement that the switching time of the two voltages must be controlled at the microsecond level.

[0163] In several embodiments provided in the present application, it is understood that each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved.

[0164] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for enabling an electronic device to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0165] The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the scope of protection of the present application. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A dual voltage power supply circuit for laser radar application, characterized in that: Specifically include: Processor, voltage conversion module, switching power supply and laser transmitter; The processor transmits high and low voltage control signals to the switching power supply; The processor transmits a PWM signal to the voltage conversion module; the voltage conversion module converts the PWM signal into an analog signal and outputs the analog signal to the switching power supply; the switching power supply outputs a corresponding output voltage to the laser transmitter according to the analog signal; The laser transmitter transmits a corresponding laser signal according to the output voltage. Wherein, the voltage conversion module includes: an RC network and an operational amplifier or a voltage follower.

2. The dual voltage power supply circuit for laser radar application according to claim 1 is characterized in that: After receiving the PWM signal transmitted by the processor, the RC network converts it into an initial analog signal and sends it to the operational amplifier or voltage follower; After receiving the initial analog signal, the operational amplifier or voltage follower outputs an analog signal to the power feedback network.

3. The dual voltage power supply circuit for laser radar application according to claim 2 is characterized in that: The switching power supply comprises: a power supply, a switching unit and a feedback network; the switching unit and the feedback network are embedded in the power supply; The switch unit receives the high and low voltage control signals and is used to quickly switch the output voltage of the switching power supply; The feedback network receives the analog signal and is used to control the output voltage of the power supply according to the analog signal.

4. The dual voltage power supply circuit for laser radar application according to claim 3 is characterized in that: The feedback network includes: a first voltage dividing unit, a second voltage dividing unit and a third voltage dividing unit. The first voltage dividing unit, the second voltage dividing unit and the third voltage dividing unit are connected to a node VFB; The first voltage dividing unit is also connected to the laser transmitter; The second voltage dividing unit is connected to the switch unit; The third voltage dividing unit is also connected to the operational amplifier or the voltage follower.

5. The dual voltage power supply circuit for laser radar application according to claim 3 is characterized in that: The second voltage dividing unit includes: a first sub-voltage dividing unit and a second sub-voltage dividing unit; the first sub-voltage dividing unit and the second sub-voltage dividing unit are connected in parallel, and the first sub-voltage dividing unit is connected to the switch unit.

6. The dual voltage power supply circuit for laser radar application according to claim 4 is characterized in that: The node VFB is connected to the power source.

7. The dual voltage power supply circuit for laser radar application according to claim 5 is characterized in that: The output voltage terminal of the feedback network is connected to the laser emitter.

8. A method for a dual voltage power supply circuit for a laser radar application based on any one of claims 1 to 7, wherein: The method comprises: S1: Output level signal according to required voltage; S2: generating an initial output voltage according to the level signal; S3: Generate a periodic PWM signal; S4: converting the PWM signal into an initial analog signal; S5: converting the initial analog signal into an analog signal; S6: According to the simulation signal, adjusting the initial output voltage to obtain an output voltage; S7: emitting a corresponding laser signal according to the output voltage.

9. The method according to claim 8, wherein the step S1 specifically comprises: When the processor outputs a high-level signal, the initial output voltage generated by the switching power supply is a high voltage; when the processor outputs a low-level signal, the initial output voltage generated by the switching power supply is a low voltage.

10. The method according to claim 9, wherein the step S6 is specifically: When the output voltage is a high output voltage, a high-power laser signal is emitted; When the output voltage is a low output voltage, a low-power laser signal is emitted.

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