Optoelectronic sensing chip

Abstract

The present application relates to an optoelectronic sensing chip having an electrical input terminal. The optoelectronic sensing chip includes an input circuit, a signal processing circuit, and a plurality of optoelectronic sensing structures connected between the input circuit and the signal processing circuit. Among them, the input circuit is connected to the electrical input terminal to obtain a working voltage; the signal processing circuit is used to receive the sensing signals of the optoelectronic sensing structures, process them, and then output. The number of signal processing circuits is less than the number of optoelectronic sensing structures; each optoelectronic sensing structure is used to sense signals, and the input ends of each optoelectronic sensing structure are connected to the input circuit through a first multiplexer, and / or the output ends of each optoelectronic sensing structure are connected to the signal processing circuit through a second multiplexer. For the above optoelectronic sensing chip, the optoelectronic sensing structures, the signal processing circuit, and the multiplexer are integrated on the same chip, reducing circuit wiring and reducing circuit parasitic effects. Moreover, by accessing the multiplexer, the number of signal processing circuits used is reduced, thereby reducing the chip power consumption and simplifying the chip structure.

Description

Technical Field

[0001] This application relates to the field of optoelectronic detection, and particularly to an optoelectronic sensing chip. Background Art

[0002] An optoelectronic sensing chip integrates an optoelectronic sensing structure and a signal processing circuit connected to the optoelectronic sensing structure. To meet the requirements of different scenarios, multiple optoelectronic sensing structures are integrated in one optoelectronic sensing signal. Each optoelectronic sensing structure is connected to each other at the input end and accesses voltage through an input circuit, and each optoelectronic sensing structure is respectively connected to a separate signal processing circuit at the output end. When the optoelectronic sensing structure generates an induction signal, it can be processed by the corresponding signal processing circuit and then output. Since multiple optoelectronic sensing structures are integrated in the optoelectronic sensing chip, the optoelectronic sensing chip can work in a variety of different scenarios, thereby improving the applicable range of the chip. However, there are many circuit distributions in the above optoelectronic sensing chip, the parasitic effect is serious, and the structure is relatively complex. At the same time, when the input circuit of the chip accesses voltage, each sensing structure and the corresponding signal processing circuit work simultaneously, resulting in a large power consumption of the chip and serious heat dissipation problems. Summary of the Invention

[0003] Based on this, in view of the problems of the current optoelectronic sensing chip with complex structure and large power consumption, it is necessary to propose a new optoelectronic sensing chip.

[0004] An optoelectronic sensing chip has an electrical input end. The optoelectronic sensing chip includes an input circuit, a signal processing circuit, and multiple optoelectronic sensing structures connected between the input circuit and the signal processing circuit, wherein,

[0005] The input circuit is connected to the electrical input end to obtain a working voltage;

[0006] The signal processing circuit is used to receive the induction signal of the optoelectronic sensing structure, process it and then output it. The number of the signal processing circuits is less than the number of the optoelectronic sensing structures;

[0007] Each of the optoelectronic sensing structures is used to sense a signal. The input ends of each of the optoelectronic sensing structures are connected to the input circuit through a first multiplexer, and / or the output ends of each of the optoelectronic sensing structures are connected to the signal processing circuit through a second multiplexer.

[0008] In one embodiment, all multiplexers are integrated in the optoelectronic sensing chip by CMOS process.

[0009] In one embodiment, the optoelectronic sensing structure is a silicon photomultiplier tube.

[0010] In one embodiment, the optoelectronic sensing structure has a single output terminal. The optoelectronic sensing chip includes M signal processing circuits and M second multiplexers. The signal processing circuits are connected to the second multiplexers in a one-to-one correspondence. Each signal processing circuit is connected to the output terminal of each optoelectronic sensing structure through an independent second multiplexer.

[0011] In one embodiment, each optoelectronic sensing structure has two output terminals, and the signal processing circuit has two input terminals. One output terminal of each optoelectronic sensing structure is connected to one input terminal of the signal processing circuit through one second multiplexer, and the other output terminal of each optoelectronic sensing structure is connected to the other input terminal of the signal processing circuit through another second multiplexer.

[0012] In one embodiment, the optoelectronic sensing chip includes M signal processing circuits and 2M second multiplexers. One input terminal of each signal processing circuit is connected to one output terminal of each optoelectronic sensing structure through an independent second multiplexer.

[0013] In one embodiment, the optoelectronic sensing chip further has M first multiplexers. Each first multiplexer is connected between the input circuit and the input terminal of each optoelectronic sensing structure.

[0014] In one embodiment, the optoelectronic sensing chip has a plurality of electrical input terminals. Each electrical input terminal is connected to the input circuit through a third multiplexer.

[0015] In one embodiment, the voltages applied to the plurality of input circuits include a minimum operating voltage, a maximum operating voltage, and intermediate voltages evenly divided from the interval between the minimum operating voltage and the maximum operating voltage.

[0016] In one embodiment, the optoelectronic sensing chip is a time-of-flight ranging sensing chip.

[0017] The above-mentioned optoelectronic sensing chip integrates an optoelectronic sensing structure, a signal processing circuit, and a multiplexer within the same semiconductor structure. Compared with an optoelectronic detector formed by assembly, it can reduce parasitic capacitance, accelerate the reaction rate, and has a relatively small chip area. Among them, each optoelectronic sensing structure is connected to an input circuit through a multiplexer at the input end, and / or each optoelectronic sensing structure is connected to a signal processing circuit through a multiplexer at the output end. When each optoelectronic sensing structure is connected to the input circuit through a multiplexer at the input end, during operation, by controlling the multiplexer, some of the optoelectronic sensing structures are selected to be connected to the input circuit. When a working voltage is applied to the electrical input end, only the optoelectronic sensing structures connected to the input circuit enter the working state, and other optoelectronic sensing structures not connected to the input circuit do not work. Thus, the chip power consumption can be reduced. At the same time, since not all optoelectronic sensing structures enter the working state, the number of corresponding signal processing circuits can be less than the number of optoelectronic sensing structures. It is sufficient to connect the partially connected optoelectronic sensing structures to the signal processing circuits. Therefore, the number of optoelectronic sensing structures can be reduced, and the chip structure can be simplified. When each optoelectronic sensing structure is connected to the signal processing circuit through a multiplexer at the output end, during operation, by controlling the multiplexer, some of the optoelectronic sensing structures are selected to be connected to the signal processing circuit. Therefore, the optoelectronic sensing structures and the signal processing circuits do not need to be connected one by one, and the number of signal processing circuits can be lower than the number of optoelectronic sensing structures. Thus, the number of signal processing circuits can be reduced, the chip structure can be simplified, and the manufacturing cost of the chip can be reduced. Description of the Drawings

[0018] Figure 1a FIG. 6 is a schematic structural diagram of an optoelectronic sensing chip of the present application connected with a first multiplexer;

[0019] Figure 1b FIG. 7 is a schematic structural diagram of another optoelectronic sensing chip of the present application connected with a first multiplexer;

[0020] Figure 2a FIG. 8 is a schematic structural diagram of an optoelectronic sensing chip of the present application connected with a second multiplexer;

[0021] Figure 2b FIG. 9 is a schematic structural diagram of another optoelectronic sensing chip of the present application connected with a second multiplexer;

[0022] Figure 2c FIG. 10 is a schematic structural diagram of yet another optoelectronic sensing chip of the present application connected with a second multiplexer;

[0023] Figure 3a FIG. 11 is a schematic structural diagram of an optoelectronic sensing chip of the present application connected with a first multiplexer and a second multiplexer;

[0024] Figure 3bSchematic structural diagram of another optoelectronic sensing chip of the present application connected with a first multiplexer and a second multiplexer;

[0025] Figure 3c Schematic structural diagram of yet another optoelectronic sensing chip of the present application connected with a first multiplexer and a second multiplexer;

[0026] Figure 4 Schematic structural diagram of an optoelectronic sensing chip with multiple electrical input ends in an embodiment of the present application. Detailed implementation manners

[0027] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. Optional embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used in the description of the present application in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0029] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be intervening elements present simultaneously.

[0030] Embodiment 1

[0031] The optoelectronic sensing chip has an electrical input terminal Vop for accessing the working voltage, and an electrical output terminal Output for outputting a processed signal. The optoelectronic sensing chip includes an input circuit, a signal processing circuit, and a plurality of optoelectronic sensing structures connected between the input circuit and the signal processing circuit. It is assumed that there are N optoelectronic sensing structures in the optoelectronic sensing chip, where N≥2. Among them, the input circuit is connected to the electrical input terminal and is used to obtain the working voltage and supply it to the optoelectronic sensing structures. The input circuit can be a circuit with a certain electrical signal adjustment function or a connecting wire segment. The optoelectronic sensing structure is connected to the input circuit and enters the working state after applying the working voltage, captures the optical signal and performs optoelectronic conversion to form an induction signal. The signal processing circuit is connected to the optoelectronic sensing structure and is used to receive the induction signal, perform signal processing and then output. And the number of signal processing circuits is less than the number of optoelectronic sensing structures. Among them, the input ends of the optoelectronic sensing structures are specifically connected to the input circuit through a multiplexer. The multiplexer defined as the first multiplexer MUX1 connected between the input ends of the optoelectronic sensing structures and the input circuit has a main connection end and a plurality of secondary connection ends. The main connection end of the first multiplexer is connected to the input circuit, and the plurality of secondary connection ends of the first multiplexer are respectively connected to the input ends of the optoelectronic sensing structures in one-to-one correspondence.

[0032] In the above optoelectronic sensing chip, since the input ends of the optoelectronic sensing structures are connected to the input circuit through the first multiplexer, turning on one first multiplexer will only allow one of the optoelectronic sensing structures connected to it to work. Therefore, it is possible to select and turn on some of the optoelectronic sensing structures to enter the working state as needed. In this embodiment, by setting the first multiplexer, when the input circuit accesses the working voltage, only some of the optoelectronic sensing structures will obtain the working voltage, enter the working state and generate induction signals. Therefore, the above electrical sensing chip does not need to be provided with signal processing circuits connected to each optoelectronic sensing structure in one-to-one correspondence, that is, the number of signal processing circuits is less than the number of optoelectronic sensing structures, and the chip structure is simple. At the same time, when the chip accesses the working voltage, only some of the optoelectronic sensing structures are selected to be in the working state and consume power, while the other optoelectronic sensing structures do not enter the working state and do not consume power. Therefore, it is beneficial to reduce the overall power consumption of the chip.

[0033] In a specific embodiment, as Figure 1a shown, the optoelectronic sensing chip has N optoelectronic sensing structures. Each optoelectronic sensing structure has a single output terminal. The input ends of the optoelectronic sensing structures are connected to an input circuit through a first multiplexer, and the output ends of the optoelectronic sensing structures are directly connected to a signal processing circuit.

[0034] In another specific embodiment, as Figure 1bAs shown, the optoelectronic sensing structure has two output terminals, such as a photomultiplier tube, defined as the first output terminal and the second output terminal. That is, an optoelectronic sensing structure can output two induction signals simultaneously. Correspondingly, the signal processing circuit also has two input terminals, defined as the first input terminal and the second input terminal. The input terminals of each optoelectronic sensing structure are connected to an input circuit through a first multiplexer. The first output terminal of each optoelectronic sensing structure is connected to the first input terminal of the signal processing circuit, and the second output terminal of each optoelectronic sensing structure is connected to the second input terminal of the signal processing circuit.

[0035] Embodiment 2

[0036] The main difference between Embodiment 2 and Embodiment 1 is that the multiplexer is connected between the output terminal of each optoelectronic sensing structure and the signal processing circuit, while the input terminal of the optoelectronic sensing structure is directly connected to the input circuit. The multiplexer connected between the optoelectronic sensing structure and the signal processing circuit is defined as the second multiplexer MUX2. That is, the main connection terminal of the second multiplexer is connected to the signal processing circuit, and multiple secondary connection terminals of the second multiplexer are connected to the output terminals of the optoelectronic sensing structure in one-to-one correspondence. In this embodiment, only one optoelectronic sensing structure is connected to one second multiplexer. Therefore, in the working mode, some optoelectronic sensing structures do not need to be connected to the signal processing circuit. Only the selected optoelectronic sensing structure needs to be connected to the signal processing circuit. Therefore, the number of signal processing circuits can be reduced, and the chip structure can be simplified.

[0037] In one embodiment, the above optoelectronic sensing structure has a single output terminal. The optoelectronic sensing chip includes M second multiplexers and M signal processing circuits, that is, the number of second multiplexers is the same as the number of signal processing, and M < N. Among them, the second multiplexers are connected to the signal processing circuits in one-to-one correspondence. Each signal processing circuit is connected to the output terminal of each optoelectronic sensing structure through an independent second multiplexer. In a specific embodiment, as Figure 2a shown, M = 1. Each optoelectronic sensing structure is directly connected to the electrical input terminal, and each optoelectronic sensing structure is connected to the signal processing circuit through a second multiplexer. At this time, the chip will only process the induction signal of one optoelectronic sensing structure at a time and output one processed signal. In another specific embodiment, as Figure 2b shown, M > 2. Each optoelectronic sensing structure is directly connected to the electrical input terminal, and multiple second multiplexers are connected between each optoelectronic sensing structure and the signal processing circuit. At this time, after the chip is connected to the working voltage, it can simultaneously process the induction signals generated by multiple optoelectronic sensing structures and output multiple processed signals.

[0038] In one embodiment, as Figure 2cAs shown in the figure, the above-mentioned optoelectronic sensing structure has two output terminals, defined as the first output terminal and the second output terminal. Correspondingly, the signal processing circuit also has two input terminals, defined as the first input terminal and the second input terminal. The above chip includes at least two second multiplexers, defined as the first multiplexer and the second multiplexer respectively. Among them, the first multiplexer is connected between the first output terminal of each optoelectronic sensing structure and the first input terminal of the signal processing circuit, and the second multiplexer is connected between the second output terminal of each optoelectronic sensing structure and the second input terminal of the signal processing circuit. In an embodiment, the optoelectronic sensing chip includes M signal processing circuits and 2M second multiplexers. One input terminal of each signal processing circuit is connected to one output terminal of each optoelectronic sensing structure through an independent second multiplexer, that is, the first input terminal of a signal processing circuit is connected to the first output terminal of each optoelectronic sensing structure through an independent second multiplexer, and the second input terminal of a signal processing circuit is also connected to the second output terminal of each optoelectronic sensing structure through an independent second multiplexer.

[0039] Embodiment 3

[0040] The difference between Embodiment 3 and Embodiment 1 is that a first multiplexer is connected between the input terminal of each optoelectronic sensing structure and the input circuit of the chip, and a second multiplexer is also connected between the output terminal of each optoelectronic sensing structure and the signal processing circuit. In this embodiment, for the chip to operate normally, both the first multiplexer and the second multiplexer need to be turned on simultaneously to select some of the optoelectronic sensing structures to connect to the working voltage and make the optoelectronic sensing structures in the working state connect to the data processing circuit. Since only some of the optoelectronic sensing structures need to perform sensing and be processed by the signal processing circuit, there is no need to set up a one-to-one connection between the signal processing circuit and the optoelectronic sensing structure, which can reduce the number of signal processing circuits and simplify the chip structure. At the same time, by setting up the first multiplexer, only the selected optoelectronic sensing structures can obtain the working voltage and enter the working state, while other unselected optoelectronic sensing structures do not obtain the working voltage and will not enter the working mode. Therefore, the power consumption of the chip can be reduced and heat dissipation can be decreased.

[0041] In one embodiment, when the optoelectronic sensing structure has a single output terminal, the chip has M first multiplexers, M second multiplexers, and M signal processing circuits. Among them, the main connection terminals of the M signal processing circuits and the M second multiplexers are connected in one-to-one correspondence. The secondary connection terminals of the M second multiplexers are respectively connected to the output terminals of the optoelectronic sensing structures. The main connection terminals of the M first multiplexers are connected to the input circuit, and the multiple secondary connection terminals of the M first multiplexers are connected to the input terminals of the optoelectronic sensing structures in one-to-one correspondence. Turn on the M first multiplexers and the M second multiplexers so that M optoelectronic sensing structures obtain the working voltage and generate M induction signals. Each induction signal is processed by the corresponding signal processing circuit and then M output signals are output. In a specific embodiment, as Figure 3a shown, M = 1. A first multiplexer and a second multiplexer are respectively connected between the optoelectronic sensing structure and the electrical input terminal and between the optoelectronic sensing structure and the signal processing circuit. At this time, when a voltage is applied to the electrical input terminal, only one optoelectronic sensing structure enters the working state, and the chip only outputs one processed signal. In another specific embodiment, as Figure 3b shown, M > 1. Multiple first multiplexers and multiple second multiplexers are respectively connected between the optoelectronic sensing structure and the electrical input terminal and between the optoelectronic sensing structure and the signal processing circuit. At this time, when a voltage is applied to the electrical input terminal, multiple optoelectronic sensing structures can be selected to enter the working state, and the chip can output multiple processed signals.

[0042] In one embodiment, as Figure 3c shown, the above optoelectronic sensing structure has two output terminals, defined as the first output terminal and the second output terminal. Correspondingly, the signal processing circuit also has two input terminals, defined as the first input terminal and the second input terminal. At least two second multiplexers are included in the above chip. One second multiplexer is connected between the first output terminal of each optoelectronic sensing structure and the first input terminal of the signal processing circuit, and the other second multiplexer is connected between the second output terminal of each optoelectronic sensing structure and the second input terminal of the signal processing circuit. In one embodiment, the chip has M first multiplexers, 2M second multiplexers, and M signal processing circuits. Among them, the connection of the M first multiplexers and the connection of the 2M second multiplexers have been introduced in detail above and will not be elaborated here.

[0043] In the above embodiments, each multiplexer is integrated into the photoelectric sensing chip through CMOS technology. In this embodiment, the photoelectric sensing structure, the signal processing circuit, and each multiplexer are all integrated into the same semiconductor chip through semiconductor technology, which can reduce parasitic capacitance, accelerate the reaction speed, and the entire chip area is small, without occupying much space. In the above embodiments, the above photoelectric sensing structure is a silicon photomultiplier (abbreviated as SiPM). In the above embodiments, the input circuit is connected to the electrical input terminal of the chip. In one embodiment, as Figure 4 shown, the chip has multiple electrical input terminals, and a multiplexer is connected between the input circuit and each electrical input terminal, which is defined as the third multiplexer. In this embodiment, the chip is provided with multiple electrical input terminals, and the electrical input terminals are connected to the input circuit through the third multiplexer. At this time, different voltages can be applied to each electrical input terminal. The chip can select the required electrical input terminal to be connected through the third multiplexer, making the chip more flexible in application. At the same time, by adjusting the connection of the multiplexer, the working voltage can be quickly switched. In one embodiment, the voltages applied to the above electrical input terminals include the minimum working voltage, the maximum working voltage, and the intermediate voltage evenly divided from the interval between the minimum working voltage and the maximum working voltage. In a specific embodiment, the above photoelectric sensing structure can be a silicon photomultiplier, a single electron avalanche diode, etc., and its working mode is the Geiger mode, and its minimum working voltage is the breakdown voltage.

[0044] In the above embodiments, the above photoelectric sensing chip is a time-of-flight ranging sensing chip. By emitting a light pulse to the target and receiving the light reflected by the object, an induction signal is generated through the above photoelectric sensing structure, and a processed signal is output through the signal processing circuit, so as to calculate the time of flight of the light pulse to and fro to obtain the distance from the target object. The above time-of-flight ranging sensing chip can be used in lidar and 3D cameras.

[0045] The above-described embodiments merely represent several implementation manners of the present application, and the description thereof is relatively specific and detailed, but should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. An optoelectronic sensing chip having an electrical input terminal, characterized in that, the optoelectronic sensing chip includes an input circuit, M signal processing circuits, a plurality of optoelectronic sensing structures connected between the input circuit and the signal processing circuits, and 2M second multiplexers, where M > 1, and all multiplexers are integrated in the optoelectronic sensing chip by CMOS process; wherein, the input circuit is connected to the electrical input terminal to obtain a working voltage; one input terminal of each signal processing circuit is connected to one output terminal of each of the optoelectronic sensing structures through an independent one of the second multiplexers, and the signal processing circuit is configured to receive the sensing signals of the optoelectronic sensing structures and output them after processing, and the number of the signal processing circuits is less than the number of the optoelectronic sensing structures; each of the optoelectronic sensing structures is configured to sense signals, the input terminals of each of the optoelectronic sensing structures are connected to the input circuit through a first multiplexer, and the output terminals of each of the optoelectronic sensing structures are connected to the signal processing circuits through the second multiplexers; wherein, each of the optoelectronic sensing structures has two output terminals, each of the signal processing circuits has two input terminals, one output terminal of each of the optoelectronic sensing structures is connected to one input terminal of the signal processing circuit through one of the second multiplexers, and the other output terminal of each of the optoelectronic sensing structures is connected to the other input terminal of the signal processing circuit through another one of the second multiplexers; when the first multiplexer and the second multiplexer are simultaneously turned on, so that some of the optoelectronic sensing structures are connected to the working voltage to enter the working state, and the part of the optoelectronic sensing structures entering the working state are connected to the data processing circuit, the optoelectronic sensing chip works normally; when a voltage is applied to the electrical input terminal, multiple ones of the optoelectronic sensing structures can be selected to enter the working state, and the optoelectronic sensing chip can output multiple processed signals.

2. The optoelectronic sensing chip according to claim 1, characterized in that, the optoelectronic sensing structure is a silicon photomultiplier.

3. The optoelectronic sensing chip according to claim 1, characterized in that, the optoelectronic sensing chip further has M of the first multiplexers, and each first multiplexer is connected between the input circuit and the input terminals of each of the optoelectronic sensing structures.

4. The optoelectronic sensing chip according to claim 1, characterized in that, the optoelectronic sensing chip has a plurality of the electrical input terminals, and each of the electrical input terminals is connected to the input circuit through a third multiplexer.

5. The optoelectronic sensing chip according to claim 4, characterized in that, the voltages applied to the plurality of input circuits include a minimum working voltage, a maximum working voltage, and an intermediate voltage evenly divided from the interval between the minimum working voltage and the maximum working voltage.

6. The optoelectronic sensing chip according to claim 1, characterized in that, the optoelectronic sensing chip is a time-of-flight ranging sensing chip.

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