Circuit and method for driving laser device array, and chip and lidar

Abstract

Provided in the embodiments of the present specification are a circuit and method for driving a laser device array, and a chip and a LiDAR. The circuit comprises a first gating device, an energy storage device, and an energy storage controller. The first gating device is coupled between a voltage source and the energy storage device and is configured to establish a connection between the voltage source and the energy storage device. The energy storage device is coupled to a first common electrode, is configured to store, when the first gating device establishes the connection, energy provided by the voltage source, and is also configured to provide the stored energy for the first common electrode, wherein a laser device array comprises the first common electrode used by a plurality of laser devices. The energy storage controller is configured to control the operating state of the energy storage device on the basis of the operating state of the first gating device, so that the energy stored in the energy storage device meets preset requirements.

Description

Circuit, method, chip and laser radar for driving laser array

[0001] This disclosure claims priority to the Chinese patent application entitled “Driving circuit, method, chip and laser radar for laser array” filed on September 27, 2023, with application number 202311270194.2. The contents of the priority application are incorporated herein by reference in their entirety. Technical Field

[0002] The embodiments of this specification relate to the field of semiconductor laser technology, and in particular to a circuit, method, chip, and laser radar for driving a laser array. Background Art

[0003] In the development of LiDAR, laser arrays have enabled higher integration of the transmitter, lower laser costs, and simpler transmitter control compared to discrete lasers. Laser arrays have a wide range of applications in LiDAR.

[0004] However, the laser array electrically connects each laser together through metal electrodes, which reduces the electrical isolation between the lasers and causes crosstalk between the lasers, thereby affecting the performance of the lidar system.

[0005] Therefore, how to reduce the crosstalk between lasers remains to be solved by those skilled in the art.

[0006] Summary of the Invention

[0007] The embodiments of this specification provide a circuit, method, chip, and laser radar for driving a laser array, which can effectively reduce the probability of crosstalk between lasers in the laser array.

[0008] First, an embodiment of this specification provides a circuit for driving a laser array, the circuit comprising:

[0009] A first gate, coupled between the voltage source and the energy storage, configured to conduct a path between the voltage source and the energy storage;

[0010] The energy storage device is coupled to the first common electrode and is configured to store energy provided by the voltage source when the first gate is turned on, and is further configured to provide the stored energy to the first common electrode, wherein the laser array includes the first common electrode shared by a plurality of lasers;

[0011] The energy storage controller is configured to control the working state of the energy storage device based on the working state of the first gate device so that the energy stored in the energy storage device meets the preset requirements.

[0012] Optionally, a first end of the energy storage is coupled to the first gate, and a second end of the energy storage is coupled to the ground.

[0013] Optionally, the energy storage controller includes a third gate, a first end of the third gate is coupled to the first end of the energy storage, and a second end of the third gate is coupled to the ground; the third gate is configured to open a path between the first end of the energy storage and the ground when the first gate is not selected to release the energy of the energy storage.

[0014] Optionally, the energy storage controller includes a fourth gate, a first end of the fourth gate is coupled to the second end of the energy storage, and the second end of the fourth gate is coupled to the ground; the fourth gate is configured to disconnect the path between the second end of the energy storage and the ground when the first gate is not selected, so that the energy storage does not store energy.

[0015] Optionally, the energy storage device includes a capacitor.

[0016] Optionally, the laser array includes a second common electrode of a plurality of lasers, and the circuit further includes:

[0017] The second gate is coupled between the second common electrode and the ground, and is configured to conduct a path between the second common electrode and the ground.

[0018] Optionally, the multiple lasers connected to the first common electrode and the multiple lasers connected to the second common electrode include at least one identical laser, and when both the first gate and the second gate are turned on, the at least one identical laser is activated to emit laser light.

[0019] Optionally, the laser array includes multiple first common electrodes and multiple second common electrodes, and the multiple lasers connected to any first common electrode and the multiple lasers connected to any second common electrode include an identical laser, so that any laser in the laser array can be individually activated to emit laser.

[0020] Optionally, the first gate includes a first switch, and the second gate includes a second switch.

[0021] Optionally, an on-resistance of the second switch is smaller than an on-resistance of the first switch.

[0022] An embodiment of this specification further provides a method for driving a laser array, the method comprising:

[0023] Conducting a path between a preset voltage source and a preset energy storage device;

[0024] storing the energy provided by the preset voltage source in a preset energy storage device, wherein the laser array includes a first common electrode shared by a plurality of lasers, and the energy storage device is configured to provide the energy stored in the preset energy storage device to the first common electrode;

[0025] Based on the on-off condition of the path between the preset voltage source and the preset energy storage device, the working state of the preset energy storage device is controlled so that the energy stored in the preset energy storage device meets the preset requirements.

[0026] An embodiment of this specification further provides a chip for driving a laser array, the chip comprising: the circuit described in any one of the above embodiments, the circuit coupled to the laser array and configured to drive the lasers in the laser array.

[0027] The embodiment of this specification further provides a laser radar, including:

[0028] Laser arrays;

[0029] The circuit described in any one of the above embodiments is coupled to the laser array and configured to drive the lasers in the laser array.

[0030] Using the circuit for driving a laser array provided in the embodiments of this specification, a first gate coupled between a voltage source and an energy storage device can conduct a path between the voltage source and the energy storage device. The energy storage device can store the energy provided by the voltage source and can provide the stored energy to the first common electrode of multiple lasers in the laser array to drive the selected lasers to emit light. The energy storage controller can also control the operating state of the energy storage device based on the operating state of the first gate device. The energy stored in the energy storage device meets the preset requirements and can effectively reduce the probability of crosstalk between the lasers in the laser array.

[0031] Optionally, a first end of the energy storage device is coupled to the first gate, and a second end is coupled to the ground. The circuit structure is simple, which is conducive to stable operation of the circuit.

[0032] Optionally, the energy storage controller may include a third gate. The first end of the third gate is coupled to the first end of the energy storage, and the second end is coupled to the ground. When the first gate is not selected, the energy storage does not need to provide energy to the first common electrode. The third gate can open the path between the first end of the energy storage and the ground, releasing the energy of the energy storage, thereby preventing the energy storage from providing energy to the first common electrode. It can also reduce the probability of crosstalk between the lasers in the laser array.

[0033] Optionally, the energy storage controller may include a fourth gate. The first end of the fourth gate is coupled to the second end of the energy storage, and the second end is coupled to the ground. When the first gate is not selected, the energy storage does not need to provide energy to the first common electrode. The fourth gate can disconnect the path between the second end of the energy storage and the ground. The energy storage does not store energy, which can prevent the energy storage from providing energy to the first common electrode. It can also reduce the probability of crosstalk between the lasers in the laser array.

[0034] Optionally, the energy storage device may include a capacitor. Storing energy through a capacitor not only simplifies the circuit structure but also reduces the cost and facilitates mass production.

[0035] Optionally, when the laser array includes a second common electrode for a plurality of lasers, the circuit may further include a second gate. The second gate is coupled between the second common electrode and ground to control the on / off state of the path between the second common electrode and ground, thereby increasing the configuration flexibility of the circuit.

[0036] Optionally, the plurality of lasers connected to the first common electrode and the plurality of lasers connected to the second common electrode include at least one identical laser. When both the first gate and the second gate are turned on, the at least one identical laser can be activated to emit laser light.

[0037] Optionally, the laser array includes a plurality of first common electrodes and a plurality of second common electrodes. The plurality of lasers connected to any first common electrode and the plurality of lasers connected to any second common electrode include the same laser. Any laser in the laser array can be individually addressed and strobed to emit laser light.

[0038] Optionally, the first gate may include a first switch. The second gate may include a second switch. Switches have low cost and long service life, which is conducive to stable operation of the circuit, while reducing the cost of the entire circuit and facilitating mass production.

[0039] Optionally, the on-resistance of the second switch can be smaller than the on-resistance of the first switch. The circuit provides the stored energy to the first common electrode via the energy storage device. The gating speed of the first switch can be relatively slow. The on-resistance of the first switch can be relatively large. As can be seen from the above, the parasitic capacitance of the first switch is relatively small, and thus the stored energy is also relatively small, which helps to further reduce crosstalk between lasers. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. The drawings described below are only embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without inventive effort.

[0041] FIG1 shows a schematic structural diagram of an exemplary circuit for driving a two-dimensional laser array.

[0042] FIG. 2 shows a schematic diagram of driving signals of the exemplary circuit shown in FIG. 1 in an anode driving mode.

[0043] FIG3 shows a schematic diagram of driving signals of the exemplary circuit shown in FIG1 in a cathode driving mode.

[0044] FIG4 shows a signal diagram of the exemplary circuit shown in FIG1 in a simultaneous anode and cathode driving mode;

[0045] FIG5 is a schematic diagram showing a path of reverse bias leakage of a laser in an anode driving mode.

[0046] FIG6 shows a schematic diagram of the structure of an exemplary circuit for driving a laser array consistent with some embodiments of the present disclosure.

[0047] FIG7 shows a schematic diagram of the structure of an exemplary circuit for driving a laser array consistent with some embodiments of the present disclosure.

[0048] FIG8 shows a schematic structural diagram of an exemplary circuit for driving a laser array in an application scenario consistent with some embodiments of the present disclosure.

[0049] FIG9 a is a schematic diagram showing a driving signal of an exemplary circuit in an anode driving mode consistent with some embodiments of the present disclosure.

[0050] FIG9 b shows a schematic diagram of the path of reverse bias leakage of a laser in an anode driving mode consistent with some embodiments of the present disclosure.

[0051] FIG10 a shows a schematic structural diagram of an exemplary circuit for driving a laser array in an application scenario consistent with some embodiments of the present disclosure.

[0052] FIG10 b shows a schematic diagram of driving signals of the circuit shown in FIG10 a .

[0053] FIG11 shows a flow chart of an exemplary method of driving a laser array, consistent with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0054] As mentioned in the background, laser arrays electrically connect individual lasers via metal electrodes, which degrades the electrical isolation between the lasers. This can lead to crosstalk between the lasers, which in turn affects the performance of the LiDAR system.

[0055] For ease of understanding, the following briefly introduces existing methods for driving laser arrays.

[0056] Refer to FIG1 for a schematic diagram of an exemplary circuit for driving a two-dimensional laser array. For ease of description, a 4*4 two-dimensional laser array is shown here. As shown in FIG1 , in the column direction, as shown by colA, colB, colC, and colD, the anodes of the four lasers are connected together and connected to the high voltage source HVDD through a switch S A 、S B 、S C 、S D In the row direction, as shown in row 1, row 2, row 3, and row 4, the cathodes of the four lasers are connected together and connected to ground (GND) through switches S1, S2, S3, and S4.

[0057] The above circuit generally has three drive modes: anode drive, cathode drive, and simultaneous anode and cathode drive. For ease of description, and continuing with Figure 1, the following uses the laser corresponding to the driving coordinate (row2, colC) (the laser indicated by the dashed box in Figure 1) as an example to illustrate the three drive modes.

[0058] Referring to FIG2 , a schematic diagram of a driving signal of the exemplary circuit shown in FIG1 under an anode driving mode, and in combination with FIG1 , the anode driving specifically refers to closing the switch S C (drive signal high level), connect the anode of the laser in row C to the high voltage power supply HVDD. Switch S2 is driven in the form of pulses. When the drive pulse is high level, switch S2 is closed. The closing time corresponds to the duration of the high level of the drive pulse. This enables the laser (row2, colC) to emit laser pulses. During the pulse emission, switch S C Can remain closed.

[0059] Referring to FIG3 , a schematic diagram of a driving signal of the exemplary circuit shown in FIG1 under a cathode driving mode, and in combination with FIG1 , cathode driving specifically refers to: closing switch S2 (driving signal high level) to connect the cathode of row 2 laser to ground. Switch S C It is driven in the form of pulses. When the driving pulse is high, the switch S CClosed. The closed duration corresponds to the duration of the high level of the drive pulse. The laser (row2, colC) can emit laser pulses. Switch S2 can remain closed during the pulse emission.

[0060] 4, a signal diagram of the exemplary circuit shown in FIG1 under a simultaneous anode and cathode driving mode, and in combination with FIG1, the simultaneous anode and cathode driving specifically refers to: switch S C The driving pulses of the two switches need to be synchronized. As shown in Figure 4, switch S C The driving pulse of switch S2 is at high level at the same time, making switch S C The switch S2 is closed at the same time. The closing time corresponds to the duration of the high level of the driving pulse, thereby driving the laser to emit laser pulses.

[0061] In some cases, the above driving method may cause crosstalk problems between lasers.

[0062] The following explanation uses the anode drive method as an example. For example, when one laser in a laser array is selected, the anode of that laser is connected to the high-voltage power supply. The switch between the laser's cathode and ground is turned on, driving the laser to emit light. When the switch between the laser's cathode and ground is turned off, the reverse bias leakage of the other unselected common-cathode lasers charges the parasitic capacitance of their anode nodes. The maximum voltage can reach the high-voltage power supply voltage. The parasitic capacitance primarily comes from the switch's parasitic capacitance.

[0063] As a specific example, refer to FIG5 for a schematic diagram of the reverse bias leakage path of the laser under an anode drive mode. C The anode of the laser in the colC column can be connected to the high voltage power supply HVDD. Closing switch S2 can select the laser (row2, colC). When the laser (row2, colC) stops emitting light and switch S2 is opened, the reverse bias leakage of the lasers in other columns that are not selected will flow to the parasitic capacitance C of the laser anode. para The maximum voltage may reach the voltage of the high voltage power supply HVDD. For example, the parasitic capacitance mainly includes the switch S C of parasitic capacitance.

[0064] When switch S2 is closed and row2 laser is selected for pulse driving, in some cases, the target laser corresponding to the coordinate (row2, colC) can be lit. However, due to the reverse bias leakage of the laser, the anode parasitic capacitance C of the lasers in other columns connected to the cathode of the target laser is increased. paraA certain amount of charge and energy is stored. When the voltage value of the anode of the laser in the other columns connected to the cathode of the target laser exceeds the voltage threshold for laser emission, the lasers in the other columns will also emit light. As shown in Figure 5, the lasers corresponding to coordinates (row2, colB), (row2, colA), and (row2, colD) may also be illuminated. This phenomenon is called crosstalk between lasers.

[0065] In response to the above problems, an embodiment of the present specification provides a circuit for driving a laser array. A first gate coupled between a voltage source and an energy storage device can conduct a path between the voltage source and the energy storage device. The energy storage device can store the energy provided by the voltage source and can provide the stored energy to the first common electrode of multiple lasers in the laser array to drive the gated lasers to emit light. The energy storage controller can also control the working state of the energy storage device. The energy stored in the energy storage device meets the preset requirements and can effectively reduce the probability of crosstalk between the lasers in the laser array.

[0066] In order to enable those skilled in the art to better understand and implement the embodiments of this specification, the concepts, schemes, principles and advantages of the embodiments of this specification are described in detail below with reference to the drawings and through specific application examples.

[0067] First, the present embodiment provides a circuit for driving a laser array, with reference to FIG6 showing an exemplary circuit structure diagram for driving a laser array. The laser array comprises a first common electrode E1 for multiple lasers. The circuit includes a first gate A1, an energy storage device A2, and an energy storage controller A3.

[0068] For example, in FIG6 , the first gate A1 is coupled between the voltage source HVDD and the energy storage A2 , and can conduct a path between the voltage source HVDD and the energy storage A2 .

[0069] The energy storage device A2 is coupled to the first common electrode E1 , and can store energy provided by the voltage source HVDD when the first gate A1 is turned on, and can also provide the stored energy to the first common electrode E1 .

[0070] The energy storage controller A3 can control the working state of the energy storage device A2 based on the working state of the first gate device A1, so that the energy stored in the energy storage device A2 meets the preset requirements.

[0071] In some embodiments, when the first gate is enabled, the operating state of the energy storage device can be controlled so that the energy stored in the energy storage device is greater than the threshold value for laser emission. When the first gate is not enabled, the operating state of the energy storage device can be controlled so that the energy stored in the energy storage device is less than the threshold value for laser emission.

[0072] In some embodiments, when the first gate is not enabled, the energy stored in the energy storage device can be made zero by controlling the working state of the energy storage device.

[0073] Using the above circuit, a first gate coupled between a voltage source and an energy storage device can conduct a path between the voltage source and the energy storage device. The energy storage device can store energy provided by the voltage source and can provide the stored energy to the first common electrode of multiple lasers in the laser array to drive the selected lasers to emit light. The energy storage controller can control the operating state of the energy storage device based on the operating state of the first gate device. The energy stored in the energy storage device meets the preset requirements and can effectively reduce the probability of crosstalk between the lasers in the laser array.

[0074] In some embodiments, a first terminal of the energy storage device is coupled to the first gate device, and a second terminal of the energy storage device is coupled to ground. In this example, the circuit structure is simple, which is conducive to stable operation of the circuit.

[0075] In some embodiments, the energy storage device may include a capacitor. A capacitor is typically composed of two metal electrodes sandwiched between a layer of insulating dielectric. When a voltage is applied between the two metal electrodes, charge accumulates on the metal electrodes, storing energy. In this example, using a capacitor for energy storage not only simplifies the circuit structure but also reduces costs, facilitating mass production.

[0076] It should be noted that the embodiments of this specification do not impose specific limitations on energy storage devices. The energy storage device can store energy. In some embodiments, the energy storage device can also include an inductor. An inductor can store electrical energy by converting it into magnetic energy.

[0077] In some embodiments, the energy storage controller may include a first gating element (or "third gate"). For example, a first end of the third gate is coupled to the first end of the energy storage device. A second end of the third gate is coupled to ground. The third gate may open a path between the first end of the energy storage device and ground to release energy from the energy storage device when the first gate is not selected.

[0078] With the above embodiment, when the first gate is not enabled, the energy storage device does not need to supply energy to the first common electrode. The third gate device can open a path between the first end of the energy storage device and ground, releasing energy from the energy storage device. This prevents the energy storage device from supplying energy to the first common electrode. This also reduces the probability of crosstalk between lasers in the laser array.

[0079] In some embodiments, the energy storage controller may include a second gating element (or referred to as a "fourth gate"). For example, a first end of the fourth gate is coupled to a second end of the energy storage device. A second end of the fourth gate is coupled to ground. The fourth gate may disconnect the path between the second end of the energy storage device and ground when the first gate is not selected, so that the energy storage device does not store energy.

[0080] With the above embodiment, when the first gate is not enabled, the energy storage device does not need to supply energy to the first common electrode. The fourth gate device can disconnect the path between the second end of the energy storage device and the ground, preventing the energy storage device from storing energy. This prevents the energy storage device from supplying energy to the first common electrode. This also reduces the probability of crosstalk between lasers in the laser array.

[0081] In some embodiments, referring to FIG. 7 , another exemplary circuit structure diagram for driving a laser array is shown. When the laser array includes a second common electrode E2 for multiple lasers, the circuit may further include a second gate A4. For example, the second gate A4 is coupled between the second common electrode E2 and ground GND, thereby conducting a conductive path between the second common electrode E2 and ground GND. Using this example, the lasers can be controlled from two electrodes, thereby increasing the control flexibility of laser driving.

[0082] For example, the plurality of lasers connected to the first common electrode and the plurality of lasers connected to the second common electrode may include at least one identical laser. When both the first gate and the second gate are turned on, the at least one identical laser is activated to emit laser light.

[0083] For example, the laser array may include multiple first common electrodes and multiple second common electrodes. The multiple lasers connected to any first common electrode and the multiple lasers connected to any second common electrode include the same laser. Each laser in the laser array can be individually addressed and activated to emit laser light.

[0084] In some embodiments, the first gate may include a first switch. The second gate may include a second switch. The switch has a low cost and a long service life, which is conducive to stable operation of the circuit, and can also reduce the cost of the entire circuit, facilitating mass production.

[0085] For example, the first switch and the second switch may include field effect transistors.

[0086] It should be noted that the embodiments of this specification do not impose any specific restrictions on the first gate and the second gate. The first gate and the second gate can realize the conduction and disconnection of the path in the circuit.

[0087] In some embodiments, the on-resistance of the second switch can be smaller than the on-resistance of the first switch. The circuit provides the stored energy to the first common electrode via the energy storage device. The first switch can have a relatively slow gating speed. The on-resistance of the first switch can be relatively large. As can be seen from the above, the parasitic capacitance of the first switch is relatively small, and thus the stored energy is also relatively small, which helps further reduce crosstalk between lasers.

[0088] In order to enable those skilled in the art to better understand and implement the embodiments of this specification, the following describes through specific examples how the circuit for driving the laser array described in the above embodiment can reduce the probability of crosstalk between the lasers in the laser array while driving the laser to emit light.

[0089] Referring to Fig. 8, an exemplary circuit structure diagram of driving a laser array in an application scenario is shown. For ease of description, this example is explained by taking driving a 4*4 laser array as an example.

[0090] Each column of four lasers in the laser array has a first common electrode. As shown in FIG8 , the first common electrode of the four lasers in column colA is E 11 The first common electrode of the four lasers in column colB is E 12 The first common electrode of the four lasers in column colC is E 13 The first common electrode of the four lasers in column colD is E 14 . There is a second common electrode for each row of 4 lasers in the laser array. As shown in FIG8 , the second common electrode of the 4 lasers in row 1 is E 21 The second common electrode of the four lasers in row 2 is E 22 The second common electrode of the 4 lasers in row 3 is E 23 The second common electrode of the 4 lasers in row 4 is E 24 .

[0091] The circuit includes first switches S arranged in different columns A , first switch S B , first switch S C , first switch S D . Wherein, a first switch is set corresponding to a column of lasers. Energy storage C1, energy storage C2, energy storage C3, and energy storage C4 are set in different columns, wherein one energy storage is set in one column. Third selectors K1, third selectors K2, third selectors K3, and third selectors K4 are set in different columns, wherein one third selector is set in one column. Second switches S1, second switch S2, second switch S3, and second switch S4 are set in different rows, wherein one second switch is set corresponding to a row of lasers.

[0092] In some embodiments, as shown in FIG8 , the first switch S A , first switch S B , first switch S C , first switch S D , respectively coupled between the voltage source HVDD and the energy storages C1, C2, C3, and C4, and can respectively conduct paths between the voltage source HVDD and the energy storages C1, C2, C3, and C4. In a column direction, the first switch in that column direction is coupled between the voltage source and the energy storages in that column direction, and can conduct paths between the voltage source and the energy storages in that column direction.

[0093] For example, in FIG8 , the first ends of the energy storage devices C1, C2, C3, and C4 are connected to the first switch S A , first switch S B , first switch S C , first switch S D The first end is also coupled to the first common electrode E 11 , first common electrode E 12 , first common electrode E 13 , first common electrode E 14 The second ends of the energy storage devices C1 to C4 are respectively coupled to the ground. The energy storage devices C1 to C4 can be connected to the first switch S A , first switch S B , first switch S C , first switch S D When turned on, the energy provided by the voltage source HVDD is stored. The energy storage devices C1 to C4 can also supply the first common electrode E 11 , first common electrode E 12 , first common electrode E 13 , first common electrode E14 Providing stored energy. In a column direction, a first end of the energy storage device is coupled to the first switch and the first common electrode. A second end of the energy storage device is coupled to ground. The energy storage device can store energy provided by the voltage source when the first switch is turned on. The energy storage device can also provide stored energy to the first common electrode.

[0094] For example, in FIG8 , the first ends of the third gates K1, K2, K3, and K4 are respectively coupled to the first ends of the energy storages C1, C2, C3, and C4. The second ends are respectively coupled to the ground. The third gates K1 to KR can be connected to the first switch S A , first switch S B , first switch S C , first switch S D When not selected, the path between the first end of the energy storage C1, energy storage C2, energy storage C3, and energy storage C4 and the ground is turned on to release the energy of the energy storage C1, energy storage C2, energy storage C3, and energy storage C4. The energy stored in the energy storage C1, energy storage C2, energy storage C3, and energy storage C4 is zero. In a column direction, the first end of the third selector is coupled to the first end of the energy storage. The second end of the third selector is coupled to the ground. The third selector can, when the first switch is not selected, turn on the path between the first end of the energy storage and the ground to release the energy of the energy storage. The energy stored in the energy storage is less than the threshold value for causing the laser to emit light.

[0095] The second switches S1, S2, S3, and S4 are respectively coupled to the second common electrode E. 21 , the second common electrode E 22 , the second common electrode E 23 , the second common electrode E 24 The second switches S1 to S4 can conduct the second common electrode E 21 , the second common electrode E 22 , the second common electrode E 23 , the second common electrode E 24 In one row direction, the second switch is coupled between the second common electrode and the ground. The second switch can conduct the path between the second common electrode and the ground.

[0096] For example, the energy storage C1 , the energy storage C2 , the energy storage C3 , and the energy storage C4 include capacitors.

[0097] For example, the first switch S A , first switch S B , first switch SC , first switch S D The third gate K1, the third gate K2, the third gate K3, the third gate K4, the second switch S1, the second switch S2, the second switch S3, and the second switch S4 include field effect transistors.

[0098] Using the above embodiment, before one of the columns of lasers is selected to emit light, the first switch is first closed to select the path between the voltage source and the corresponding energy storage. The energy storage can store the energy provided by the voltage source and can also provide the stored energy to the first common electrode of the selected column of lasers. For other unselected columns, the path between the ground and the energy storage is selected by the third selector to release the charge on the energy storage. Keeping the energy storage in the energy storage at zero can effectively reduce the probability of crosstalk between the lasers in the laser array. When the second switch is closed to drive the laser to emit light, the laser pulse energy mainly comes from the energy storage. The discharge path of the energy storage is short and can provide high-amplitude narrow pulses, which can drive the laser to emit narrow pulses of laser light. During the pulsed light emission process, the energy storage remains connected to the voltage source to replenish the energy consumed by the laser light emission.

[0099] The following takes the driving of the laser corresponding to the coordinate (row2, colC) as an example to describe in detail the driving process of the circuit for driving the laser array shown in FIG8 .

[0100] Referring to Figures 9a and 9b, Figure 9a shows a schematic diagram of the driving signal of an exemplary circuit in the anode driving mode. Figure 9b shows a schematic diagram of the path of the reverse bias leakage of the laser in the anode driving mode. When the target laser corresponding to the driving coordinate (row2, colC) emits light, the second common electrode E is shared with the target laser. 22 The lasers of the other columns (colA, colB, colD) are in reverse bias state. The third gate K1, the third gate K2 and the third gate K4 are closed, so that the reverse bias leakage of the lasers of the other columns that are not selected flows directly to the ground (the reverse bias leakage path of the laser of the colB column as shown by the dotted arrow in Figure 9b). Ensure that no charge is accumulated on the energy storage C2, which can reduce the second common electrode E shared with the target laser. 22 It can also reduce the probability of crosstalk between lasers in the laser array.

[0101] With this circuit, the laser's instantaneous current loop includes a third gate. This reduces the number of gate components, which helps increase the laser's peak optical power. Furthermore, because the energy storage device requires a slower gate speed, the internal resistance of the first switch must be lower than that of the second switch. The internal resistance of the first switch can be relatively large. The internal resistance of the second switch is smaller than that of the first switch.

[0102] In some embodiments, referring to Figures 10a and 10b , Figure 10a illustrates a schematic diagram of a circuit structure for driving a laser array in an application scenario. Figure 10b illustrates a schematic diagram of a driving signal for the circuit shown in Figure 10a . For ease of description, this example uses driving a 4*4 laser array as an example.

[0103] Each column of four lasers in the laser array has a first common electrode. As shown in FIG10a, the first common electrode of the four lasers in column colA is E 11 The first common electrode of the four lasers in column colB is E 12 The first common electrode of the four lasers in column colC is E 13 The first common electrode of the four lasers in column colD is E 14 . There is a second common electrode for each row of 4 lasers in the laser array. As shown in FIG8 , the second common electrode of the 4 lasers in row 1 is E 21 The second common electrode of the four lasers in row 2 is E 22 The second common electrode of the 4 lasers in row 3 is E 23 The second common electrode of the 4 lasers in row 4 is E 24 .

[0104] The circuit includes first switches S arranged in different columns A , first switch S B , first switch S C , first switch S D . A first switch is set corresponding to a column of lasers. Energy storage devices C1, C2, C3, and C4 are set in different columns, and one energy storage device is set in one column. Fourth selectors G1, G2, G3, and G4 are set in different columns, and one third selector is set in one column. Second switches S1, S2, S3, and S4 are set in different rows, and one second switch is set corresponding to a row of lasers.

[0105] In some embodiments, as shown in FIG10 a, the first switch S A , first switch S B , first switch S C , first switch S D , respectively coupled between the voltage source HVDD and the energy storage devices C1, C2, C3, and C4. The first switch S A ~S DThe first switch is coupled between the voltage source HVDD and the energy storages C1, C2, C3, and C4 in a column direction, and can conduct the path between the voltage source and the energy storages in the column direction.

[0106] The first ends of the energy storage devices C1, C2, C3 and C4 are connected to the first switch S A , first switch S B , first switch S C , first switch S D coupled to the first common electrode E 11 , first common electrode E 12 , first common electrode E 13 , first common electrode E 14 The second ends of the energy storage devices C1 to C4 are coupled to the first ends of the fourth gate devices G1, G2, G3 and G4 respectively. The energy storage devices C1 to C4 can be connected to the first switch S A , first switch S B , first switch S C , first switch S D When turned on, the energy provided by the voltage source HVDD is stored. The energy storage devices C1 to C4 can also supply the first common electrode E 11 , first common electrode E 12 , first common electrode E 13 , first common electrode E 14 Providing stored energy. In a column direction, a first end of the energy storage device is coupled to the first switch and the first common electrode. A second end of the energy storage device is coupled to a first end of the fourth gate. The energy storage device can store energy provided by the voltage source when the first switch is turned on. The energy storage device can also provide stored energy to the first common electrode.

[0107] The first ends of the fourth gates G1, G2, G3 and G4 are coupled to the second ends of the energy storages C1, C2, C3 and C4 respectively. The second ends of the fourth gates G1 to G4 are coupled to the ground respectively. The fourth gates G1 to G4 can be connected to the first switch S A , first switch S B , first switch S C , first switch S DWhen not selected, the path between the second end of the energy storage C1, energy storage C2, energy storage C3, and energy storage C4 and the ground is disconnected. The energy storage C1, energy storage C2, energy storage C3, and energy storage C4 do not store energy. In a column direction, the first end of the fourth selector is coupled to the second end of the energy storage. The second end of the fourth selector is coupled to the ground. The fourth selector can disconnect the path between the second end of the energy storage and the ground when the first switch is not selected. The energy storage does not store energy, which can ensure that the energy stored in the energy storage is less than the threshold value for causing the laser to emit light.

[0108] The second switches S1, S2, S3, and S4 are respectively coupled to the second common electrode E. 21 , the second common electrode E 22 , the second common electrode E 23 , the second common electrode E 24 The second switches S1 to S4 can conduct the second common electrode E 21 , the second common electrode E 22 , the second common electrode E 23 , the second common electrode E 24 In one row direction, the second switch is coupled between the second common electrode and the ground, and can conduct the path between the second common electrode and the ground.

[0109] In some embodiments, the energy storage C1 , the energy storage C2 , the energy storage C3 , and the energy storage C4 include capacitors.

[0110] In some embodiments, the first switch S A , first switch S B , first switch S C , first switch S D The fourth gate G1, the fourth gate G2, the fourth gate G3, the fourth gate G4, the second switch S1, the second switch S2, the second switch S3, and the second switch S4 include field effect transistors.

[0111] Using the above embodiment, when one column of lasers is selected to emit light, the first switch and the fourth selector of the column are closed, and the energy storage device can store the energy provided by the voltage source and also provide the stored energy to the first common electrode of the selected column of lasers. For other unselected columns, the first switch and the fourth selector are both disconnected, so that one end of the energy storage device is floating and cannot accumulate charge. As a result, the energy storage device can be kept at zero, effectively reducing the probability of crosstalk between the lasers in the laser array. When the second switch is closed to drive the laser to emit light, the laser pulse energy mainly comes from the energy storage device. The discharge path of the energy storage device is short. The energy storage device can provide high-amplitude narrow pulses and can drive the laser to emit narrow pulses of laser light. During the pulsed light emission process, the energy storage device remains connected to the voltage source to replenish the energy consumed by the laser light emission.

[0112] The following takes the driving of the laser corresponding to the coordinate (row2, colC) as an example to describe in detail the driving process of the circuit for driving the laser array shown in FIG10a.

[0113] When the target laser corresponding to the driving coordinate (row2, colC) emits light, the first switch S is closed. C And the fourth gate G3. Turn off the first switch S A , first switch S B , first switch S D , and the fourth gate G1, the fourth gate G2, and the fourth gate G4, so that one end of the energy storage C1, the energy storage C2, and the energy storage C4 are floating and cannot accumulate charge. This can ensure that the second common electrode E is shared with the target laser. 22 The lasers in other columns will not emit light, and there will be no laser crosstalk problem.

[0114] The embodiments of this specification also provide a method for driving a laser array. Referring to the flowchart of a method for driving a laser array shown in FIG11 , wherein the laser array includes first common electrodes of multiple lasers, the laser array can be driven using the following steps:

[0115] Step A: connecting a path between a preset voltage source and a preset energy storage device.

[0116] Step B: storing the energy provided by the preset voltage source in a preset energy storage device, and providing the energy stored in the preset energy storage device to the first common electrode.

[0117] Step C: Based on the on-off status of the path between the preset voltage source and the preset energy storage device, controlling the working state of the preset energy storage device so that the energy stored in the preset energy storage device meets the preset requirements.

[0118] In the above embodiment, by conducting a path between a preset voltage source and a preset energy storage device, energy provided by the preset voltage source is stored in the preset energy storage device. The stored energy is then supplied to the first common electrode of multiple lasers in the laser array via the energy storage device to drive the selected lasers to emit light. The operating state of the preset energy storage device is controlled based on the on / off state of the path between the preset voltage source and the preset energy storage device. This ensures that the energy stored in the preset energy storage device meets preset requirements, effectively reducing the probability of crosstalk between the lasers in the laser array.

[0119] In addition, embodiments of this specification also provide a driver chip capable of driving a laser array. The driver chip may include any of the aforementioned laser array driving circuits. The circuit is coupled to the laser array to drive the lasers in the laser array.

[0120] In addition, the embodiments of this specification also provide a laser radar, which includes a laser array and a circuit.

[0121] The circuit may be any one of the circuits for driving a laser array in the aforementioned embodiments. The circuit is coupled to the laser array and may drive the lasers in the laser array.

[0122] By adopting the above embodiment, the circuit for driving the laser array used by the laser radar can effectively reduce the probability of crosstalk between the lasers in the laser array, and can improve the performance of the laser radar system.

[0123] Although the embodiments of this specification are disclosed above, the present invention is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be based on the scope defined by the claims.

Claims

1. A circuit for driving a laser array, the circuit comprising: A first gate, coupled between the voltage source and the energy storage device, configured to conduct a path between the voltage source and the energy storage device; The energy storage device is coupled to the first common electrode and is configured to store energy provided by the voltage source when the first gate is turned on, and is also configured to provide the stored energy to the first common electrode, wherein the laser array includes the first common electrode shared by a plurality of lasers; The energy storage controller is configured to control the working state of the energy storage device based on the working state of the first selector, so that the energy stored in the energy storage device meets the preset requirements.

2. The circuit according to claim 1, characterized in that A first end of the energy storage device is coupled to the first gate, and a second end of the energy storage device is coupled to the ground.

3. The circuit according to claim 2, characterized in that The energy storage controller includes a third gate, a first end of the third gate is coupled to the first end of the energy storage device, and a second end of the third gate is coupled to the ground; the third gate is configured to open a path between the first end of the energy storage device and the ground to release the energy of the energy storage device when the first gate is not selected.

4. The circuit according to claim 2, characterized in that The energy storage controller includes a fourth gate, a first end of the fourth gate is coupled to the second end of the energy storage device, and a second end of the fourth gate is coupled to the ground; the fourth gate is configured to disconnect the path between the second end of the energy storage device and the ground when the first gate is not selected, so that the energy storage device does not store energy.

5. The circuit according to any one of claims 2 to 4, characterized in that: The energy storage device includes a capacitor.

6. The circuit according to claim 1, characterized in that The laser array includes a second common electrode of a plurality of lasers, and the circuit further includes: The second gate is coupled between the second common electrode and the ground, and is configured to conduct a path between the second common electrode and the ground.

7. The circuit according to claim 6, characterized in that The multiple lasers connected to the first common electrode and the multiple lasers connected to the second common electrode include at least one identical laser. When both the first gate and the second gate are turned on, the at least one identical laser is activated to emit laser light.

8. The circuit according to claim 6, characterized in that The laser array includes a plurality of first common electrodes and a plurality of second common electrodes. The plurality of lasers connected to any first common electrode and the plurality of lasers connected to any second common electrode include an identical laser, so that any laser in the laser array can be individually activated to emit laser light.

9. The circuit according to claim 6, characterized in that The first gate includes a first switch, and the second gate includes a second switch.

10. The circuit according to claim 9, characterized in that An on-resistance of the second switch is smaller than an on-resistance of the first switch.

11. A method for driving a laser array, the method comprising: Conducting a path between a preset voltage source and a preset energy storage device; storing the energy provided by the preset voltage source in a preset energy storage device, wherein the laser array comprises a first common electrode shared by a plurality of lasers, and the energy storage device is configured to provide the energy stored in the preset energy storage device to the first common electrode; Based on the on-off condition of the path between the preset voltage source and the preset energy storage device, the working state of the preset energy storage device is controlled so that the energy stored in the preset energy storage device meets the preset requirements.

12. A chip for driving a laser array, the chip comprising: The circuit according to any one of claims 1 to 10, wherein the circuit is coupled to the laser array and configured to drive the lasers in the laser array.

13. A laser radar, comprising: Laser arrays; The circuit of any one of claims 1 to 10, coupled to the laser array and configured to drive the lasers in the laser array.

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