Test control system and method for monolithic integrated pixel signal

Abstract

The invention relates to a test control system and method for monolithic integrated pixel signals, and belongs to the field of signal test control. The integrated detector converts a micro-current generated by the detection unit or a test current signal input out of a chip into a voltage signal, then carries out amplitude amplification on the voltage, can control an output signal through an output end control circuit, and finally outputs a pulse signal meeting the amplitude requirement according to the output use requirement. Control of a micro-current signal and an external input signal of an on-chip detection pixel, signal amplification processing and low-delay signal output mode control are realized. According to the invention, the advantages of the control circuit, the detection unit and the signal processing circuit are combined to realize monolithic technology integration, different input test conditions and signal output use requirements can be met, and the evaluation efficiency of the function and performance of the signal processing circuit is effectively improved. The control method has the performance characteristics of rapidness, high processing speed, low signal delay, easiness in on-chip integration and the like.

Description

Technical Field

[0001] The invention belongs to the field of signal test control and relates to a test control system and method for a single-chip integrated pixel signal. Background Art

[0002] As detector application systems develop towards miniaturization, high integration and low cost, the connection solutions between traditional discrete devices such as detectors and amplifier circuits can no longer meet application requirements. Monolithic integrated structure detectors have the advantages of small area, low packaging cost and small parasitics, and are widely used in optical communications, detection and other fields. With the development of process integration technology, silicon-based detectors are gradually integrated with standard processes. This integration method integrates the detector unit and the signal processing circuit on the same chip, further improving the integration and performance. However, after the monolithic integration of the detection pixel and the signal processing circuit, independent testing and evaluation of the performance of the signal processing circuit has become an inoperable technical problem. At the same time, facing the diverse usage requirements of signal output modes, how to achieve low-cost and high-efficiency testing of the on-chip signal processing circuit performance and control of different output modes has become a technical problem that needs to be solved urgently.

[0003] Existing testing methods often require separating the detector unit from the signal processing circuit for separate testing, which not only increases the complexity and cost of the test, but also fails to truly reflect the performance of the monolithic integrated structure detector in actual applications.

[0004] Therefore, in view of the above problems, the present invention provides a test control method for monolithic integrated pixel signals, which can effectively solve the difficult problem of testing and evaluating monolithic integrated structure detectors and realize the control of different output modes, and has important application value. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a test control system and method for monolithic integrated pixel signals.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A test control system for a monolithic integrated pixel signal, the system comprising:

[0008] Signal input part:

[0009] Photodiode: Receives light signals and converts them into micro-current signals;

[0010] Input control module: includes transistors T1, T2 and resistor R1; the base of T1 is connected to the control signal input terminal VC1; the emitter of T1 is connected to the base and collector of T2; the base and collector of T2 are short-circuited to form a diode; VC2 is a fixed voltage signal input terminal; when the control signal input terminal is at a high level, the transistor is turned on, the diode is in a reverse bias state, and no current enters the input terminal of the on-chip circuit; when the control signal input terminal is at a low level, the transistor is turned off, the diode is in a forward bias state, and a micro current is generated to enter the input terminal of the on-chip signal circuit;

[0011] Signal processing part:

[0012] The first stage amplifier A1: converts the current signal into a voltage signal; it adopts a transimpedance amplifier circuit structure, with a transistor and its collector connected to a resistor forming a front common-emitter amplifier, a transistor and its emitter connected to a resistor forming a rear emitter follower, and a feedback resistor connecting the base of the first transistor and the emitter of the second transistor;

[0013] Capacitor C and resistor RC: connect the first-stage amplifier and the second-stage amplifier to reduce signal noise interference and adjust the gain of the subsequent stage;

[0014] The second stage amplifier A2: amplifies the voltage signal to a certain amplitude; adopts a five-tube amplifier circuit structure with double-ended input and single-ended output, with the base of two PNP tubes as double-ended input tubes, the emitter of the PNP tube as single-ended output, the base of two NPN tubes connected to form a current mirror as an active load, the PNP tube connects the power supply and the collector of the PNP input tube to form a current source load to provide bias current for the amplifier circuit; the feedback loop from node B to node A provides a reference voltage for the base of the PNP input tube;

[0015] Signal output part:

[0016] Transistors T3 and T4, resistors R3, R4 and R5, and diode D1: adjust the output resistance and the DC point of the next stage; the base of T3 is the input end of the A2 signal; the collector of T3 is connected to the base of resistor R3 and T4; the emitter of T4 is connected to R4 and R5; the diode D1 is forward connected between the base and collector of T4;

[0017] Output control module: including transistors T5, T6, T7, resistors R7, R8, R9, diodes D2, D3, and the collector of transistor T6 outputs logic control signals; the base of T5 is the control signal input terminal; the emitter of T5 is connected to resistors R7 and R8, and is connected to the base of T6; the diode D2 is forwardly connected between the base and collector of T6; the collector of T6 is connected to resistor R9 and the base of T7; the diode D3 is connected between the base and collector of T7;

[0018] Transistor T8 and diode D4: form a collector output circuit structure to adjust the output drive capability; diode D4 is forwardly connected across the base and collector of T8;

[0019] Output load: Use pull-up structure resistor to output a signal that meets the requirements of driving force and leakage current;

[0020] Reference voltage module:

[0021] Provide suitable reference voltage for detector unit and amplifier circuit.

[0022] Furthermore, the first-stage amplifier adopts a transimpedance amplifier circuit structure, including a transistor and its collector connected to a resistor to form a pre-emitter amplifier, a transistor and its emitter connected to a resistor to form a post-emitter follower, and a feedback resistor is connected across the base of the first transistor and the emitter of the second transistor.

[0023] Furthermore, the second-stage amplifier adopts a five-tube amplifier circuit structure with dual-end input and single-end output, including the base of two PNP tubes as dual-end input tubes, the emitter of the PNP tube as a single-ended output, the bases of two NPN tubes are connected to form a current mirror to become an active load, and the PNP tube is connected to the power supply and the collector of the PNP input tube to form a current source load to provide bias current for the amplifier circuit.

[0024] Furthermore, the output driving stage includes a transistor and a diode, the base of the transistor is the amplifier output signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the anode of the diode, and the cathode of the diode is connected to the reference voltage input terminal.

[0025] Furthermore, the output control module includes a transistor, the base of the transistor is the control signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the base of the output transistor, and the emitter of the output transistor is connected to the reference voltage input terminal.

[0026] Furthermore, the output control module also includes a transistor and a diode, the base of the transistor is the control signal input terminal, the emitter of the transistor is connected to the resistor, the other end of the resistor is connected to the collector of the transistor and the base of the output transistor, the emitter of the output transistor is connected to the reference voltage input terminal, and the diode is connected between the base and collector of the output transistor.

[0027] A test control method for a monolithic integrated pixel signal, the method comprising:

[0028] The input signal is controlled by the input control module to control the presence or absence of the input signal; wherein, controlling the input signal includes controlling the base voltage of the transistor, controlling the conduction state of the diode, and further controlling whether the micro-current enters the input end of the on-chip circuit;

[0029] When the input control signal is at a high level, the photodiode converts the light signal into a current signal;

[0030] When the input control signal is at a low level, a micro-current signal is generated by the external circuit;

[0031] Convert the current signal into a voltage signal through the first-stage amplifier;

[0032] Amplify the voltage signal to a certain amplitude through the second-stage amplifier;

[0033] driving the output signal through the output driver stage;

[0034] The output mode of the output signal is controlled by the output control module to be a normal pulse signal or a constant high-level signal; when the control signal of the output control module is at a high level, the output transistor is turned on, and the output signal is a normal pulse signal; when the control signal of the output control module is at a low level, the output transistor is turned off, and the output signal is a constant high-level signal; the output control module includes a transistor and a diode, the base of the transistor is the control signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the base of the output transistor, the emitter of the output transistor is connected to the reference voltage input terminal, and the diode is connected between the base and the collector of the output transistor;

[0035] Provide reference voltage for detector unit and amplifier circuit.

[0036] Furthermore, the first-stage amplifier adopts a transimpedance amplifier circuit structure to convert the current signal into a voltage signal.

[0037] Furthermore, the second-stage amplifier adopts a five-tube amplifier circuit structure with dual-end input and single-end output to amplify the voltage signal to a certain amplitude.

[0038] Furthermore, the output driving stage includes a transistor and a diode, the base of the transistor is the amplifier output signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the anode of the diode, and the cathode of the diode is connected to the reference voltage input terminal.

[0039] The beneficial effects of the present invention are: on the basis of ensuring the performance of the monolithic integrated detection unit and the signal processing circuit, the control of the micro-current signal of the on-chip detection pixel and the external input signal, signal amplification processing, and low-latency signal output mode control are realized, which greatly increases the convenience of integrated device control and testing. The characteristic of this technical solution is that it combines the respective advantages of the control circuit, the detection unit and the signal processing circuit to realize monolithic technology integration, which can meet different input test conditions and signal output usage requirements, and effectively improve the evaluation efficiency of the signal processing circuit function and performance. The present invention has the performance characteristics of quick control method, fast processing speed, low signal delay, and easy on-chip integration. It has good application value and is suitable for application in miniaturized, highly integrated, low-cost detector chips or application systems.

[0040] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0042] Figure 1 is a flow chart of processing of detector signals;

[0043] Figure 2 To test the control circuit structure connection diagram;

[0044] Figure 3 This is a diagram showing the relationship between the output signal and the control logic. DETAILED DESCRIPTION

[0045] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and the features in the embodiments can be combined with each other without conflict.

[0046] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0047] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0048] The technical solution adopted by the present invention is: the technical invention converts the microcurrent generated by the detection unit or the test current signal input from outside the chip into a voltage signal, and then amplifies the voltage amplitude. Through the output end control circuit, the output signal can be controlled, and according to the output use requirements, a digital pulse signal that meets the amplitude requirements is finally output. The test control method of the monolithic integrated pixel signal includes: an input control module, a photodiode, a first-stage amplifier, a second-stage amplifier, an output drive stage, an output control module, a reference voltage, and a reference module. Figure 1 shown.

[0049] Figure 1 The on-chip integrated signal processing flow is as follows: first, the detection unit converts the optical signal into a current signal or a test current signal input from outside the chip and inputs it into the first-stage amplifier A1; the first-stage amplifier converts the input current signal into a voltage signal through a resistor feedback amplifier circuit; the second-stage amplifier A2 amplifies the output signal of the previous stage to a voltage signal with a certain amplitude requirement; finally, the output driver stage outputs the signal and adjusts the driving capability of the output load; the first-stage amplifier and the second-stage amplifier are connected by a capacitor to avoid mutual interference between the DC operating points of the first-stage amplifier and the second-stage circuit and transmission of AC signals; the reference voltage module provides a suitable reference voltage for the detector unit and the amplifier circuit; the input signal control module provides a test current signal; and the output control module can control and adjust the output mode of the signal.

[0050] exist Figure 2In the test control circuit structure connection diagram, the overall circuit structure consists of three parts: signal input, signal processing, and signal output. Among them, the signal input part is composed of reference voltage, on-chip detection unit and control circuit of input test signal; the signal processing part is composed of first-stage amplifier, second-stage amplifier, and isolation capacitor; the signal output part is composed of common-emitter amplifier and source follower circuit, output control circuit, and output drive circuit.

[0051] The signal input part consists of two parts: the detector unit and the test signal input from outside the chip. Under the reverse bias voltage state generated by the reference voltage module 1 and the module 2, the detection unit is used to convert the optical signal into a micro-current signal. The circuit structure of the test signal input from outside the chip consists of transistors T1, T2 and resistor R1. The base of transistor T1 is the control signal input terminal VC1, and its emitter is connected to the base and collector of T2. The base and collector of transistor T2 are short-circuited to form a diode, and VC2 is a fixed voltage signal input terminal. When VC1 is high, transistor T1 is turned on, pulling down the base voltage of transistor T2, and T2 is shorted to form a diode in a reverse bias state, and no current enters the input terminal of the on-chip circuit. When VC1 is low, transistor T1 is turned off, and the voltage greater than the forward conduction voltage of the diode can be increased through the base of transistor T2, and a micro-current is generated through the diode to enter the input terminal of the on-chip signal circuit. Therefore, when the monolithic integrated device is working normally, VC1 is connected to a high-level control signal, the base of transistor T2 is in a floating state, and the detection unit provides a photogenerated microcurrent to enter the signal processing circuit; when it is necessary to test and evaluate the performance of the on-chip signal processing circuit, VC1 is connected to a low-level control signal, and a voltage value greater than the forward conduction voltage of the diode is increased at the base of transistor T2. At this time, a microcurrent is generated through the diode and enters the on-chip signal circuit.

[0052] The signal processing circuit structure includes two-stage amplifiers. The first-stage amplifier A1 can convert the current signal into a voltage signal. The amplifier circuit adopts a conventional transimpedance amplifier circuit structure. Feedback resistors are connected in parallel at the input and output ends to form a voltage parallel negative feedback, so that the amplifier circuit has the characteristics of low input impedance, large bandwidth, high gain, etc. The transimpedance amplifier circuit structure is composed of a transistor and its collector connected to a resistor to form a pre-emitter amplifier, a transistor and its emitter connected to a resistor to form a post-emitter follower, and the feedback resistor is connected across the base of the first transistor and the emitter of the second transistor. The second-stage amplifier A2 adopts a conventional double-ended input and single-ended output five-tube amplifier circuit structure, which can amplify the voltage signal output by the first-stage amplifier circuit to an appropriate amplitude for processing by the subsequent circuit. Its circuit structure is: the base of two PNP tubes is used as a double-ended input tube, the emitter of the PNP tube is a single-ended output, and the base of two NPN tubes is connected to form a current mirror to become an active load. The PNP tube is connected to the power supply and the collector of the PNP input tube to form a current source load to provide bias current for the amplifier circuit. The feedback loop from node B to node A mainly provides a reference voltage for the base of the PNP input tube. The first-stage amplifier circuit and the second-stage amplifier circuit are connected through capacitor C and resistor RC, which can reduce signal noise interference and adjust the gain of the subsequent stage.

[0053] The signal output circuit structure consists of three parts. The first part consists of transistors T3 and T4, resistors R3, R4 and R5, and diode D1. This circuit structure can adjust the output resistance and the DC point of the next stage. The base of transistor T3 is the input end of the A2 signal, the collector of T3 is connected to the base of resistors R3 and T4, the emitter of transistor T4 is connected to R4 and R5, and the diode D1 is forward connected between the base and collector of T4. The second part is the output control circuit, which mainly controls and adjusts the output mode of the signal, such as Figure 3As shown, when VC3 is at a high level, transistor T5 is turned on, T6 is turned on, T7 is turned off, and the output signal Vout is a normal pulse signal of Vin. When VC3 is at a low level, transistor T5 is turned off, T6 is turned off, T7 is turned on, the output transistor is forced to be turned off, and the output signal Vout is a constant high level. The circuit structure connection relationship is: the base of transistor T5 is the control signal input terminal, its emitter is connected to resistors R7 and R8, and is connected to the base of transistor T6, diode D2 is forwardly connected between the base and collector of T6, the collector of transistor T6 is connected to resistor R9 and the base of transistor T7, diode D3 is connected between the base and collector of T7, and the collector of transistor T6 outputs a logic control signal. The third part is a collector output circuit structure formed by transistor T8 and diode D4. Diode D4 is forwardly connected across the base and collector of transistor T8. This circuit structure can adjust the output drive capability. The output load adopts a pull-up structure resistor, which can output a signal that meets the requirements of driving force, leakage current, etc. The function of diodes D1, D2, D3, and D4 is to increase the charge discharge speed and the switching speed of the transistor.

[0054] The present invention converts the photogenerated current of the detection unit into a voltage signal, and performs signal processing such as voltage amplification, low latency and low output leakage, and finally outputs a voltage or digital signal that meets the amplitude requirements, thereby realizing on-chip real-time low-latency processing and fast data rate output of the current signal.

[0055] The working process of this implementation is explained in detail below. Figure 1 It is a processing flow chart of the detector signal, which illustrates the signal processing flow of the monolithic integrated detector, including: input control module, photodiode, first-stage amplifier, second-stage amplifier, output driver stage, output control module, reference voltage, and reference module; Figure 2 To test the control circuit structure connection diagram, the connection relationship of the circuit structure such as input signal control, signal amplification processing, and output signal control is recorded; Figure 3 This is a diagram showing the relationship between the output signal and the control logic, which illustrates the relationship between the VC1 control signal and the output signal.

[0056] The working process of this embodiment is as follows:

[0057] Figure 1The on-chip integrated signal processing flow is as follows: first, the detection unit converts the optical signal into a current signal or a test current signal input from outside the chip and inputs it into the first-stage amplifier A1; the first-stage amplifier converts the input current signal into a voltage signal through a resistor feedback amplifier circuit; the second-stage amplifier A2 amplifies the output signal of the previous stage to a voltage signal with a certain amplitude requirement; finally, the output driver stage outputs the signal and adjusts the driving capability of the output load; the first-stage amplifier and the second-stage amplifier are connected by a capacitor to avoid mutual interference between the DC operating points of the first-stage amplifier and the second-stage circuit and transmission of AC signals; the reference voltage module provides a suitable reference voltage for the detector unit and the amplifier circuit; the input signal control module provides a test current signal; and the output control module can control and adjust the output mode of the signal.

[0058] exist Figure 2 In the test control circuit structure connection diagram, the overall circuit structure consists of three parts: signal input, signal processing, and signal output. Among them, the signal input part is composed of reference voltage, on-chip detection unit and control circuit of input test signal; the signal processing part is composed of first-stage amplifier, second-stage amplifier, and isolation capacitor; the signal output part is composed of common-emitter amplifier and source follower circuit, output control circuit, and output drive circuit.

[0059] The signal input part consists of two parts: the detector unit and the test signal input from outside the chip. Under the reverse bias voltage state generated by the reference voltage module 1 and the module 2, the detection unit is used to convert the optical signal into a micro-current signal. The circuit structure of the test signal input from outside the chip consists of transistors T1, T2 and resistor R1. The base of transistor T1 is the control signal input terminal VC1, and its emitter is connected to the base and collector of T2. The base and collector of transistor T2 are short-circuited to form a diode, and VC2 is a fixed voltage signal input terminal. When VC1 is high, transistor T1 is turned on, pulling down the base voltage of transistor T2, and T2 is shorted to form a diode in a reverse bias state, and no current enters the input terminal of the on-chip circuit. When VC1 is low, transistor T1 is turned off, and the voltage greater than the forward conduction voltage of the diode can be increased through the base of transistor T2, and a micro-current is generated through the diode to enter the input terminal of the on-chip signal circuit. Therefore, when the monolithic integrated device is working normally, VC1 is connected to a high-level control signal, the base of transistor T2 is in a floating state, and the detection unit provides a photogenerated microcurrent to enter the signal processing circuit; when it is necessary to test and evaluate the performance of the on-chip signal processing circuit, VC1 is connected to a low-level control signal, and a voltage value greater than the forward conduction voltage of the diode is increased at the base of transistor T2. At this time, a microcurrent is generated through the diode and enters the on-chip signal circuit.

[0060] The signal processing circuit structure includes two-stage amplifiers. The first-stage amplifier A1 can convert the current signal into a voltage signal. The amplifier circuit adopts a conventional transimpedance amplifier circuit structure. Feedback resistors are connected in parallel at the input and output ends to form a voltage parallel negative feedback, so that the amplifier circuit has the characteristics of low input impedance, large bandwidth, high gain, etc. The transimpedance amplifier circuit structure is composed of a transistor and its collector connected to a resistor to form a pre-emitter amplifier, a transistor and its emitter connected to a resistor to form a post-emitter follower, and the feedback resistor is connected across the base of the first transistor and the emitter of the second transistor. The second-stage amplifier A2 adopts a conventional double-ended input and single-ended output five-tube amplifier circuit structure, which can amplify the voltage signal output by the first-stage amplifier circuit to an appropriate amplitude for processing by the subsequent circuit. Its circuit structure is: the base of two PNP tubes is used as a double-ended input tube, the emitter of the PNP tube is a single-ended output, and the base of two NPN tubes is connected to form a current mirror to become an active load. The PNP tube is connected to the power supply and the collector of the PNP input tube to form a current source load to provide bias current for the amplifier circuit. The feedback loop from node B to node A mainly provides a reference voltage for the base of the PNP input tube. The first-stage amplifier circuit and the second-stage amplifier circuit are connected through capacitor C and resistor RC, which can reduce signal noise interference and adjust the gain of the subsequent stage.

[0061] The signal output circuit structure consists of three parts. The first part consists of transistors T3 and T4, resistors R3, R4 and R5, and diode D1. This circuit structure can adjust the output resistance and the DC point of the next stage. The base of transistor T3 is the input end of the A2 signal, the collector of T3 is connected to the base of resistors R3 and T4, the emitter of transistor T4 is connected to R4 and R5, and the diode D1 is forward connected between the base and collector of T4. The second part is the output control circuit, which mainly controls and adjusts the output mode of the signal, such as Figure 3As shown, when VC3 is at a high level, transistor T5 is turned on, T6 is turned on, T7 is turned off, and the output signal Vout is a normal pulse signal of Vin. When VC3 is at a low level, transistor T5 is turned off, T6 is turned off, T7 is turned on, the output transistor is forced to be turned off, and the output signal Vout is a constant high level. The circuit structure connection relationship is: the base of transistor T5 is the control signal input terminal, its emitter is connected to resistors R7 and R8, and is connected to the base of transistor T6, diode D2 is forwardly connected between the base and collector of T6, the collector of transistor T6 is connected to resistor R9 and the base of transistor T7, diode D3 is connected between the base and collector of T7, and the collector of transistor T6 outputs a logic control signal. The third part is a collector output circuit structure formed by transistor T8 and diode D4. Diode D4 is forwardly connected across the base and collector of transistor T8. This circuit structure can adjust the output drive capability. The output load adopts a pull-up structure resistor, which can output a signal that meets the requirements of driving force, leakage current, etc. The function of diodes D1, D2, D3, and D4 is to increase the charge discharge speed and the switching speed of the transistor.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A test control system for monolithic integrated pixel signals, characterized in that: The system includes: Signal input part: Photodiode: Receives light signals and converts them into micro-current signals; Input control module: includes transistors T1, T2 and resistor R1; the base of T1 is connected to the control signal input terminal VC1; the emitter of T1 is connected to the base and collector of T2; the base and collector of T2 are short-circuited to form a diode; VC2 is a fixed voltage signal input terminal; when the control signal input terminal is at a high level, the transistor is turned on, the diode is in a reverse bias state, and no current enters the input terminal of the on-chip circuit; when the control signal input terminal is at a low level, the transistor is turned off, the diode is in a forward bias state, and a micro current is generated to enter the input terminal of the on-chip signal circuit; Signal processing part: The first stage amplifier A1: converts the current signal into a voltage signal; it adopts a transimpedance amplifier circuit structure, with a transistor and its collector connected to a resistor forming a front common-emitter amplifier, a transistor and its emitter connected to a resistor forming a rear emitter follower, and a feedback resistor connecting the base of the first transistor and the emitter of the second transistor; Capacitor C and resistor RC: connect the first-stage amplifier and the second-stage amplifier to reduce signal noise interference and adjust the gain of the subsequent stage; The second stage amplifier A2: amplifies the voltage signal to a certain amplitude; adopts a five-tube amplifier circuit structure with double-ended input and single-ended output, with the base of two PNP tubes as double-ended input tubes, the emitter of the PNP tube as single-ended output, the base of two NPN tubes connected to form a current mirror as an active load, the PNP tube connects the power supply and the collector of the PNP input tube to form a current source load to provide bias current for the amplifier circuit; the feedback loop from node B to node A provides a reference voltage for the base of the PNP input tube; Signal output part: Transistors T3 and T4, resistors R3, R4 and R5, and diode D1: adjust the output resistance and the DC point of the next stage; the base of T3 is the input end of the A2 signal; the collector of T3 is connected to the base of resistor R3 and T4; the emitter of T4 is connected to R4 and R5; the diode D1 is forward connected between the base and collector of T4; Output control module: including transistors T5, T6, T7, resistors R7, R8, R9, diodes D2, D3, and the collector of transistor T6 outputs logic control signals; the base of T5 is the control signal input terminal; the emitter of T5 is connected to resistors R7 and R8, and is connected to the base of T6; the diode D2 is forwardly connected between the base and collector of T6; the collector of T6 is connected to resistor R9 and the base of T7; the diode D3 is connected between the base and collector of T7; Transistor T8 and diode D4: form a collector output circuit structure to adjust the output drive capability; diode D4 is forwardly connected across the base and collector of T8; Output load: Use pull-up structure resistor to output a signal that meets the requirements of driving force and leakage current; Reference voltage module: Provide suitable reference voltage for detector unit and amplifier circuit.

2. The test control system for monolithic integrated pixel signals according to claim 1, characterized in that: The first-stage amplifier adopts a transimpedance amplifier circuit structure, including a transistor and its collector connected to a resistor to form a front common-emitter amplifier, a transistor and its emitter connected to a resistor to form a rear emitter follower, and a feedback resistor is connected across the base of the first transistor and the emitter of the second transistor.

3. The test control system for monolithic integrated pixel signals according to claim 1, characterized in that: The second-stage amplifier adopts a five-tube amplifier circuit structure with dual-end input and single-end output, including the base of two PNP tubes as dual-end input tubes, the emitter of the PNP tube as a single-ended output, the bases of two NPN tubes are connected to form a current mirror to become an active load, and the PNP tube is connected to the power supply and the collector of the PNP input tube to form a current source load to provide bias current for the amplifier circuit.

4. The test control system for monolithic integrated pixel signals according to claim 1, characterized in that: The output driving stage includes a transistor and a diode, the base of the transistor is the amplifier output signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the positive electrode of the diode, and the negative electrode of the diode is connected to the reference voltage input terminal.

5. The test control system for monolithic integrated pixel signals according to claim 1, characterized in that: The output control module comprises a transistor, the base of the transistor is a control signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the base of the output transistor, and the emitter of the output transistor is connected to a reference voltage input terminal.

6. The test control system for monolithic integrated pixel signals according to claim 1, characterized in that: The output control module also includes a transistor and a diode, the base of the transistor is the control signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the base of the output transistor, the emitter of the output transistor is connected to the reference voltage input terminal, and the diode is connected between the base and the collector of the output transistor.

7. A test control method for monolithic integrated pixel signals, characterized in that: The method includes: The input signal is controlled by the input control module to control the presence or absence of the input signal; wherein, controlling the input signal includes controlling the base voltage of the transistor, controlling the conduction state of the diode, and further controlling whether the micro-current enters the input end of the on-chip circuit; When the input control signal is at a high level, the photodiode converts the light signal into a current signal; When the input control signal is at a low level, a micro-current signal is generated by the external circuit; Convert the current signal into a voltage signal through the first-stage amplifier; Amplify the voltage signal to a certain amplitude through the second-stage amplifier; driving the output signal through the output driver stage; The output mode of the output signal is controlled by the output control module to be a normal pulse signal or a constant high-level signal; when the control signal of the output control module is at a high level, the output transistor is turned on, and the output signal is a normal pulse signal; when the control signal of the output control module is at a low level, the output transistor is turned off, and the output signal is a constant high-level signal; the output control module includes a transistor and a diode, the base of the transistor is the control signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the base of the output transistor, the emitter of the output transistor is connected to the reference voltage input terminal, and the diode is connected between the base and the collector of the output transistor; Provide reference voltage for detector unit and amplifier circuit.

8. The method for testing and controlling a monolithic integrated pixel signal according to claim 7, characterized in that: The first-stage amplifier adopts a transimpedance amplifier circuit structure to convert the current signal into a voltage signal.

9. The method for testing and controlling a monolithic integrated pixel signal according to claim 7, characterized in that: The second-stage amplifier adopts a five-tube amplifier circuit structure with dual-end input and single-end output to amplify the voltage signal to a certain amplitude.

10. The test control method of monolithic integrated pixel signal according to claim 7, characterized in that: The output driving stage includes a transistor and a diode, the base of the transistor is the amplifier output signal input terminal, the emitter of the transistor is connected to a resistor, the other end of the resistor is connected to the collector of the transistor and the positive electrode of the diode, and the negative electrode of the diode is connected to the reference voltage input terminal.

Images