Photoelectric sensing chip

Abstract

The invention relates to a photoelectric sensing chip which is provided with an electric input end, the photoelectric sensing chip comprises an input circuit, a signal processing circuit and a plurality of photoelectric sensing structures connected between the input circuit and the signal processing circuit, and the input circuit is connected with the electric input end to obtain working voltage; the signal processing circuits are used for receiving induction signals of the photoelectric sensing structures, processing the induction signals and then outputting the induction signals, and the number of the signal processing circuits is smaller than that of the photoelectric sensing structures; the photoelectric sensing structures are used for sensing signals, the input ends of the photoelectric sensing structures are connected with the input circuit through the first multiplexer, and / or the output ends of the photoelectric sensing structures are connected with the signal processing circuit through the second multiplexer. According to the photoelectric sensing chip, the multiplexer is connected, so that the number of used signal processing circuits is reduced, the power consumption of the chip is reduced, and the structure of the chip is simplified.

Description

Technical Field

[0001] The present application relates to the field of photoelectric detection, and in particular to a photoelectric sensor chip. Background Art

[0002] Photoelectric sensor chips integrate photoelectric sensor structures and signal processing circuits connected to the photoelectric sensor structures. To meet the needs of different occasions, multiple photoelectric sensor structures are integrated into a photoelectric sensor signal. Each photoelectric sensor structure is interconnected at the input end and receives voltage through the input circuit. Each photoelectric sensor structure is connected to a separate signal processing circuit at the output end. When the photoelectric sensor structure generates a sensing signal, it is processed by the corresponding signal processing circuit and then output. Because the photoelectric sensor chip integrates multiple photoelectric sensor structures, the photoelectric sensor chip can be placed in a variety of different occasions and operate, thereby increasing the chip's applicability. However, the circuits in the above-mentioned photoelectric sensor chip are distributed in a large number of places, with serious parasitic effects and a relatively complex structure. At the same time, when the chip's input circuit receives voltage, each sensor structure and the corresponding signal processing circuit operate simultaneously, resulting in high chip power consumption and serious heat dissipation problems. Summary of the Invention

[0003] Based on this, it is necessary to propose a new photoelectric sensor chip to address the problems of complex structure and high power consumption of current photoelectric sensor chips.

[0004] A photoelectric sensor chip has an electrical input terminal, the photoelectric sensor chip includes an input circuit, a signal processing circuit and a plurality of photoelectric sensing structures connected between the input circuit and the signal processing circuit, wherein:

[0005] The input circuit is connected to the electrical input terminal to obtain the operating voltage;

[0006] The signal processing circuit is used to receive the sensing signal of the photoelectric sensing structure and output it after processing. The number of the signal processing circuits is less than the number of the photoelectric sensing structures.

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

[0008] In one embodiment, all multiplexers are integrated into the photoelectric sensor chip through CMOS technology.

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

[0010] In one embodiment, the photoelectric sensing structure has a single output end, the photoelectric 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, and each signal processing circuit is connected to the output end of each photoelectric sensing structure through an independent second multiplexer.

[0011] In one embodiment, each of the photoelectric sensing structures has two output ends, and the signal processing circuit has two input ends. One of the output ends of each of the photoelectric sensing structures is connected to one of the input ends of the signal processing circuit via a second multiplexer, and another of the output ends of each of the photoelectric sensing structures is connected to another of the input ends of the signal processing circuit via another second multiplexer.

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

[0013] In one embodiment, the photoelectric sensor chip further has M first multiplexers, and each first multiplexer is connected between the input circuit and the input end of each photoelectric sensor structure.

[0014] In one embodiment, the photoelectric sensor chip has a plurality of electrical input terminals, and each of the electrical input terminals is connected to the input circuit via a third multiplexer.

[0015] In one embodiment, the voltages connected to the plurality of input circuits include a minimum operating voltage, a maximum operating voltage, and an intermediate voltage equally divided between the minimum operating voltage and the maximum operating voltage.

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

[0017] The above-mentioned photoelectric sensor chip integrates the photoelectric sensor structure, signal processing circuit, and multiplexer into the same semiconductor structure. Compared with photodetectors formed by assembly, it can reduce parasitic capacitance, accelerate reaction rate, and reduce the overall chip area. In particular, each photoelectric sensor structure is connected to the input circuit through the multiplexer at the input end, and / or each photoelectric sensor structure is connected to the signal processing circuit through the multiplexer at the output end. Each photoelectric sensor structure is connected to the input circuit through the multiplexer at the input end. During operation, by controlling the multiplexer, some of the photoelectric sensor structures are selected to be connected to the input circuit. When the input end is connected to the operating voltage, only the photoelectric sensor structures connected to the input circuit enter the operating state, and the other photoelectric sensor structures not connected to the input circuit do not operate. This can reduce chip power consumption. At the same time, because not all photoelectric sensor structures enter the operating state, the number of corresponding signal processing circuits can be less than the number of photoelectric sensor structures. It is sufficient to connect the partially connected photoelectric sensor structures to the signal processing circuit. Therefore, the number of photoelectric sensor structures can be reduced and the chip structure can be simplified. Each photoelectric sensing structure is connected to a signal processing circuit at its output end through a multiplexer. During operation, the multiplexer is controlled to select some of the photoelectric sensing structures to be connected to the signal processing circuit. Therefore, the photoelectric sensing structures and the signal processing circuits do not have to be connected one-to-one. The number of signal processing circuits can be lower than the number of photoelectric sensing structures, thereby reducing the number of signal processing circuits, simplifying the chip structure, and reducing the manufacturing cost of the chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1a This is a schematic structural diagram of a photoelectric sensor chip connected to a first multiplexer in this application;

[0019] Figure 1b This is a schematic structural diagram of another photoelectric sensor chip connected to a first multiplexer in this application;

[0020] Figure 2a This is a schematic structural diagram of a photoelectric sensor chip connected to a second multiplexer in this application;

[0021] Figure 2b This is a schematic structural diagram of another photoelectric sensor chip connected to a second multiplexer in this application;

[0022] Figure 2c This is a structural diagram of another photoelectric sensor chip connected to a second multiplexer in the present application;

[0023] Figure 3a This is a schematic structural diagram of a photoelectric sensor chip connected to a first multiplexer and a second multiplexer in the present application;

[0024] Figure 3bThis is a schematic structural diagram of another photoelectric sensor chip connected to a first multiplexer and a second multiplexer in the present application;

[0025] Figure 3c This is a structural diagram of another photoelectric sensor chip connected to a first multiplexer and a second multiplexer in the present application;

[0026] Figure 4 FIG. 1 is a schematic structural diagram of a photoelectric sensor chip having multiple electrical input terminals according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings illustrate alternative embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.

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

[0030] Example 1

[0031] The photoelectric sensor chip has an electrical input terminal Vop for receiving the working voltage and an electrical output terminal Output for outputting the processed signal. The photoelectric sensor chip includes an input circuit, a signal processing circuit, and multiple photoelectric sensor structures connected between the input circuit and the signal processing circuit. The photoelectric sensor chip can be provided with N photoelectric sensor structures, N ≥ 2; wherein, the input circuit is connected to the electrical input terminal to obtain the working voltage and transmit it to the photoelectric sensor structure. The input circuit can be a circuit with a certain electrical signal conditioning function or a connecting wire; the photoelectric sensor structure is connected to the input circuit, and after the working voltage is input, it enters the working state and captures the optical signal And perform photoelectric conversion to form a sensing signal. The signal processing circuit is connected to the photoelectric sensing structure to receive the sensing signal and output it after signal processing. The number of signal processing circuits is less than the number of photoelectric sensing structures. The input end of each photoelectric sensing structure is specifically connected to the input circuit through a multiplexer. The multiplexer connected between the input end of each photoelectric sensing structure and the input circuit is defined as a first multiplexer MUX1. The multiplexer has a main connection end and multiple secondary connection ends. The main connection end of the first multiplexer is connected to the input circuit, and the multiple secondary connection ends of the first multiplexer are connected one-to-one with the input end of each photoelectric sensing structure.

[0032] In the aforementioned photoelectric sensor chip, since the input terminals of each photoelectric sensor structure are connected to the input circuit via a first multiplexer, turning on a first multiplexer only activates one of the connected photoelectric sensor structures. Therefore, certain photoelectric sensor structures can be selectively turned on and put into operation as needed. In this embodiment, by providing the first multiplexer, when the input circuit is connected to an operating voltage, only certain photoelectric sensor structures receive the operating voltage, enter an operating state, and generate sensing signals. Therefore, the aforementioned photoelectric sensor chip does not need to include a signal processing circuit connected to each photoelectric sensor structure. That is, the number of signal processing circuits is smaller than the number of photoelectric sensor structures, simplifying the chip structure. Furthermore, when the chip is connected to an operating voltage, only certain photoelectric sensor structures are selected to be in an operating state and consume power, while the remaining photoelectric sensor structures remain inactive and do not consume power, thereby reducing overall chip power consumption.

[0033] In a specific embodiment, if Figure 1a As shown, the photoelectric sensor chip has N photoelectric sensor structures, each photoelectric sensor structure has a single output end, the input end of each photoelectric sensor structure is connected to an input circuit through a first multiplexer, and the output end of each photoelectric sensor structure is directly connected to a signal processing circuit.

[0034] In another specific embodiment, Figure 1bAs shown, the photoelectric sensing structure has two output ends, such as a photomultiplier tube, which are defined as a first output end and a second output end. That is, one photoelectric sensing structure can output two sensing signals at the same time. Correspondingly, the signal processing circuit also has two input ends, which are defined as a first input end and a second input end. The input end of each photoelectric sensing structure is connected to an input circuit through a first multiplexer. The first output end of each photoelectric sensing structure is connected to the first input end of the signal processing circuit, and the second output end of each photoelectric sensing structure is connected to the second input end of the signal processing circuit.

[0035] Example 2

[0036] The main difference between Example 2 and Example 1 is that a multiplexer is connected between the output terminals of each photoelectric sensor structure and the signal processing circuit, while the input terminals of the photoelectric sensor structures are directly connected to the input circuit. The multiplexer connected between the photoelectric sensor structures and the signal processing circuit is defined as a second multiplexer MUX2. Specifically, the primary connection terminal of the second multiplexer is connected to the signal processing circuit, and the secondary connection terminals of the second multiplexer are connected one-to-one with the output terminals of the photoelectric sensor structures. In this embodiment, each second multiplexer connects only one photoelectric sensor structure. Therefore, in the operating mode, some photoelectric sensor structures do not need to be connected to the signal processing circuit. Only the selected photoelectric sensor structures need to be connected to the signal processing circuit. This reduces the number of signal processing circuits and simplifies the chip structure.

[0037] In one embodiment, the above-mentioned photoelectric sensor structure has a single output terminal, and the photoelectric sensor 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 circuits, M<N, wherein the second multiplexers are connected to the signal processing circuits in a one-to-one correspondence, and each signal processing circuit is connected to the output terminal of each photoelectric sensor structure through an independent second multiplexer. In a specific embodiment, if Figure 2a As shown, M=1, each photoelectric sensing structure is directly connected to the electrical input terminal, and each photoelectric sensing structure is connected to the signal processing circuit through a second multiplexer. In this case, the chip will only process the sensing signal of one photoelectric sensing structure at a time and output one processed signal. In another specific embodiment, as Figure 2b As shown, M>2, each photoelectric sensing structure is directly connected to the electrical input terminal, and multiple second multiplexers are connected between each photoelectric sensing structure and the signal processing circuit. At this time, after the chip is connected to the operating voltage, it can simultaneously process the sensing signals generated by its multiple photoelectric sensing structures and output multi-channel processed signals.

[0038] In one embodiment, if Figure 2cAs shown, the photoelectric sensor structure has two output terminals, defined as a first output terminal and a second output terminal. Correspondingly, the signal processing circuit also has two input terminals, defined as a first input terminal and a second input terminal. The chip includes at least two second multiplexers, defined as a first multiplexer and a second multiplexer, respectively. The first multiplexer is connected between the first output terminal of each photoelectric sensor structure and the first input terminal of the signal processing circuit, and the second multiplexer is connected between the second output terminal of each photoelectric sensor structure and the second input terminal of the signal processing circuit. In one embodiment, the photoelectric sensor chip includes M signal processing circuits and 2M second multiplexers. One of the input terminals of each signal processing circuit is connected to one of the output terminals of each photoelectric sensor structure via an independent second multiplexer. That is, the first input terminal of a signal processing circuit is connected to the first output terminal of each photoelectric sensor structure via an independent second multiplexer, and the second input terminal of a signal processing circuit is also connected to the second output terminal of each photoelectric sensor structure via an independent second multiplexer.

[0039] Example 3

[0040] The difference between Example 3 and Example 1 is that the chip has a first multiplexer connected between the input end of each photoelectric sensor structure and the input circuit, and a second multiplexer connected between the output end of each photoelectric sensor structure and the signal processing circuit. In this embodiment, normal operation of the chip requires the simultaneous connection of the first multiplexer and the second multiplexer, selecting some of the photoelectric sensor structures to be connected to the operating voltage, and connecting the photoelectric sensor structures that have entered the operating state to the data processing circuit. Since only some of the photoelectric sensor structures are required for sensing and processing through the signal processing circuit, there is no need to set up a one-to-one correspondence between the signal processing circuit and the photoelectric sensor 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 photoelectric sensor structures are allowed to obtain the operating voltage and enter the operating state. The other unselected photoelectric sensor structures do not obtain the operating voltage and will not enter the operating mode, thereby reducing the chip's power consumption and heat dissipation.

[0041] In one embodiment, when the photoelectric sensing structure has a single output terminal, the chip has M first multiplexers, M second multiplexers, and M signal processing circuits, wherein the M signal processing circuits and the main connection terminals of the M second multiplexers are connected one-to-one, the secondary connection terminals of the M second multiplexers are respectively connected to the output terminals of each photoelectric sensing structure, 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 one-to-one to the input terminals of each photoelectric sensing structure. The M first multiplexers and the M second multiplexers are connected so that the M photoelectric sensing structures therein obtain the operating voltage and generate M-channel sensing signals, and each sensing signal is processed by the corresponding signal processing circuit and then outputs M-channel output signals. In a specific embodiment, if Figure 3a As shown, M=1, a first multiplexer and a second multiplexer are connected between the photoelectric sensing structure and the electrical input terminal, and between the photoelectric sensing structure and the signal processing circuit, respectively. In this case, when the electrical input terminal is connected to a voltage, only one photoelectric sensing structure enters the working state, and the chip only outputs one processing signal. In another specific embodiment, as Figure 3b As shown, M>1, multiple first multiplexers and multiple second multiplexers are respectively connected between the photoelectric sensing structure and the electrical input terminal, and between the photoelectric sensing structure and the signal processing circuit. At this time, when the electrical input terminal is connected to a voltage, multiple photoelectric sensing structures can be selected to enter the working state, and the chip can output multi-channel processing signals.

[0042] In one embodiment, if Figure 3c As shown, the photoelectric sensing structure has two output terminals, defined as a first output terminal and a second output terminal. Correspondingly, the signal processing circuit also has two input terminals, defined as a first input terminal and a second input terminal. The chip includes at least two second multiplexers, one of which is connected between the first output terminal of each photoelectric 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 photoelectric 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. The connections of the M first multiplexers and the 2M second multiplexers have been described in detail above and will not be repeated here.

[0043] In each of the above embodiments, each multiplexer is integrated into the photoelectric sensor chip through CMOS technology. In this embodiment, the photoelectric sensor structure, signal processing circuit, and each multiplexer are all integrated into the same semiconductor chip through semiconductor technology, which can reduce parasitic capacitance, speed up the reaction speed, and reduce the entire chip area, so it does not take up much space. In each of the above embodiments, the above-mentioned photoelectric sensor structure is a silicon photomultiplier (SiPM). In each of the above embodiments, the input circuit is connected to the electrical input terminal of the chip. In one embodiment, Figure 4 As 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 a 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 via a third multiplexer. In this case, each electrical input terminal can be connected to a different voltage. The chip can select the required electrical input terminal through the third multiplexer, making the chip application more flexible. At the same time, by adjusting the connection of the multiplexer, the operating voltage can be quickly switched. In one embodiment, the voltages connected to each of the above-mentioned electrical input terminals include a minimum operating voltage, a maximum operating voltage, and an intermediate voltage that is evenly distributed between the minimum and maximum operating voltages. In a specific embodiment, the above-mentioned photoelectric sensing structure can be a silicon photomultiplier tube, a single electron avalanche diode, etc., and its operating mode is Geiger mode, and its minimum operating voltage is the breakdown voltage.

[0044] In each of the above embodiments, the photoelectric sensor chip is a time-of-flight ranging sensor chip. By emitting a light pulse toward a target and receiving light reflected from the object, the photoelectric sensor structure generates a sensing signal. This signal is then processed by a signal processing circuit to calculate the round-trip flight time of the light pulse to determine the distance to the target. This time-of-flight ranging sensor chip can be used in lidar and 3D cameras.

[0045] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A photoelectric sensor chip having an electrical input terminal, characterized in that: The photoelectric sensor chip includes M input circuits, M signal processing circuits, N photoelectric sensor structures connected between the input circuits and the signal processing circuits, M first multiplexers, and M second multiplexers, where M>2 and N>M. The input circuit is connected to the electrical input terminal to obtain the operating voltage; The first multiplexer has a main connection terminal and a plurality of secondary connection terminals. The main connection terminal of the first multiplexer is connected to the input circuit, and the plurality of secondary connection terminals of the first multiplexer are connected to the input terminals of the photoelectric sensing structures in a one-to-one correspondence. One first multiplexer is connected to one photoelectric sensing structure. The second multiplexer has a main connection terminal and multiple secondary connection terminals. The main connection terminal of the second multiplexer is connected to the signal processing circuit, and the multiple secondary connection terminals of the second multiplexer are connected to the output terminals of the photoelectric sensing structure in a one-to-one correspondence. One second multiplexer is connected to one photoelectric sensing structure. The signal processing circuit is used to receive the sensing signal of the photoelectric sensing structure and output it after processing; Each of the photoelectric sensing structures is used to sense a signal, an input end of each of the photoelectric sensing structures is connected to the input circuit via the first multiplexer, and an output end of each of the photoelectric sensing structures is connected to the signal processing circuit via the second multiplexer; When the first multiplexer and the second multiplexer are turned on at the same time, so that part of the photoelectric sensing structure is connected to the working voltage to enter the working state, and the part of the photoelectric sensing structure that has entered the working state is connected to the signal processing circuit, the photoelectric sensor chip works normally.

2. The photoelectric sensor chip according to claim 1, wherein: All multiplexers are integrated into the photoelectric sensor chip through CMOS technology.

3. The photoelectric sensor chip according to claim 1, wherein: The photoelectric sensing structure is a silicon photomultiplier tube.

4. The photoelectric sensor chip according to claim 1, wherein: When one of the first multiplexers and one of the second multiplexers are turned on at the same time, so that the corresponding photoelectric sensor structure is connected to the working voltage to enter the working state, and the photoelectric sensor structure that has entered the working state is connected to the signal processing circuit, the photoelectric sensor chip works normally.

5. The photoelectric sensor chip according to claim 1, wherein: When multiple first multiplexers and multiple second multiplexers are turned on at the same time, so that the corresponding multiple photoelectric sensing structures are connected to the working voltage to enter the working state, and the multiple photoelectric sensing structures entering the working state are connected to the signal processing circuit, the photoelectric sensor chip works normally.

6. The photoelectric sensor chip according to claim 1, wherein: Each of the photoelectric sensing structures has two output ends, and the signal processing circuit has two input ends. One of the output ends of each of the photoelectric sensing structures is connected to one of the input ends of the signal processing circuit via a second multiplexer, and another of the output ends of each of the photoelectric sensing structures is connected to another of the input ends of the signal processing circuit via another second multiplexer.

7. The photoelectric sensor chip according to claim 6, wherein: The photoelectric sensor chip includes 2M second multiplexers, and one input end of each signal processing circuit is connected to a The independent second multiplexer is connected to one of the output terminals of each of the photoelectric sensing structures.

8. The photoelectric sensor chip according to claim 1, wherein: The photoelectric sensor chip has a plurality of electrical input terminals, and each of the electrical input terminals is connected to the input circuit via a third multiplexer.

9. The photoelectric sensor chip according to claim 8, wherein: The voltages connected to the plurality of input circuits include a minimum operating voltage, a maximum operating voltage, and an intermediate voltage equally divided between the minimum operating voltage and the maximum operating voltage.

10. The photoelectric sensor chip according to claim 1, wherein: The photoelectric sensor chip is a time-of-flight ranging sensor chip.

Images