Diode leakage current test circuit and diode test apparatus

Abstract

The utility model discloses a kind of diode leakage current test circuit and diode testing equipment, including I / V conversion module, inverter, voltage buffer module and relay module.I / V conversion module includes first operational amplifier chip and RC network unit, the first input end of first operational amplifier chip is connected with the first end of RC network unit, the output end of first operational amplifier chip is connected with the second end of RC network unit;Inverter includes second operational amplifier chip and first resistance, the first input end of second operational amplifier chip is connected with the first end of first resistance, the second end of first resistance is connected with the output end of first operational amplifier chip;Voltage buffer module includes third operational amplifier chip and second resistance;Relay module includes first relay and second relay.By I / V conversion module, smaller current is converted into larger voltage value for reading, improve test precision and test efficiency.

Description

Technical Field

[0001] This utility model relates to the field of diode testing technology, and in particular to a diode leakage current testing circuit and diode testing equipment. Background Technology

[0002] The reverse leakage current of diodes is typically in the nA to pA range, which is extremely weak and difficult to test. Existing technologies have the following problems: First, noise suppression: noise introduced by power supply ripple, ground loops, and electromagnetic radiation may overwhelm the signal under test; second, large measurement errors: insufficient input impedance can lead to voltage load effects, causing the measured value to be too low; third, significant interference: instantaneous voltage overshoot from high-voltage switching may damage the device under test or interfere with the reading; fourth, low testing efficiency and high cost. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a diode leakage current testing circuit and diode testing equipment, which uses an I / V conversion module to convert a relatively small current into a relatively large voltage value for reading, thereby improving testing accuracy and efficiency.

[0004] On one hand, this utility model embodiment provides a diode leakage current testing circuit, including: The I / V conversion module includes a first operational amplifier chip and an RC network unit. The first input terminal of the first operational amplifier chip is connected to the first terminal of the RC network unit, and the output terminal of the first operational amplifier chip is connected to the second terminal of the RC network unit. The I / V conversion module is used to convert current signals into voltage signals. An inverter, comprising a second operational amplifier chip and a first resistor, wherein a first end of the first resistor is connected to a first input terminal of the second operational amplifier chip and a second end of the first resistor is connected to an output terminal of the first operational amplifier chip, the inverter being used to convert a negative voltage into a positive voltage; A voltage buffer module includes a third operational amplifier chip and a second resistor. The first end of the second resistor is connected to the first input terminal of the third operational amplifier chip, and the second end of the second resistor is connected to the output terminal of the second operational amplifier chip. The voltage buffer module is used to stably output voltage. The relay module includes a first relay and a second relay. The first relay is connected to the first input terminal of a first operational amplifier chip, and the second relay is connected to the output terminal of a third operational amplifier chip.

[0005] According to some embodiments of the present invention, the RC network unit includes a first capacitor and a third resistor connected in parallel.

[0006] According to some embodiments of the present invention, the first relay is connected to a relay matrix module, which is used for multi-channel testing.

[0007] According to some embodiments of the present invention, the relay matrix module includes multiple third relays connected in parallel, and each third relay is connected to a light-emitting diode.

[0008] According to some embodiments of the present invention, the relay matrix module is connected to a relay drive module, the relay drive module including a data conversion chip and a Darlington driver, and the input terminal of the Darlington driver is connected to the I / O terminal of the data conversion chip.

[0009] According to some embodiments of the present invention, the relay drive module is connected to an I2C adapter, the I2C adapter includes an I2C isolator and an I2C switch, and the I2C isolator is connected to the I2C switch.

[0010] According to some embodiments of the present invention, the diode leakage current test circuit further includes a constant current source module, which is provided with a current buffer unit and is used to test the breakdown voltage of the diode.

[0011] According to some embodiments of the present invention, the diode leakage current test circuit further includes a power supply module, which includes a power management chip and is used to supply power.

[0012] According to some embodiments of the present invention, the first operational amplifier chip is an integrated circuit with model number ADA4530-1ARZ-R7.

[0013] On the other hand, this utility model embodiment provides a diode testing device, including the above-mentioned I / V conversion module.

[0014] The embodiments of this utility model have at least the following beneficial effects: The diode leakage current test circuit of this embodiment includes an I / V conversion module, an inverter, a voltage buffer module, and a relay module. The main function of the I / V conversion module is to convert a current signal into a voltage signal. In the I / V conversion module, a first operational amplifier chip works with an RC network unit to accurately convert a relatively small current into a relatively large voltage value. The inverter, through a second operational amplifier chip and a first resistor, converts a negative voltage into a positive voltage, facilitating the forward operation of the voltage buffer module. The voltage buffer module, through a third operational amplifier chip and a second resistor, buffers the converted voltage signal to ensure a stable output voltage. The relay module, through a first relay, ensures that the current signal is safely and reliably transmitted to the input terminal of the operational amplifier chip, and outputs a stable voltage signal through a second relay. The I / V conversion module converts the detected current signal into a voltage signal, which, after being adjusted and processed by the inverter and voltage buffer module, is finally output stably through the second relay. This facilitates the acquisition of voltage using a high-precision instrument-grade analog-to-digital converter to complete the diode leakage current test. By converting a relatively small current into a relatively large voltage value for reading through the I / V conversion module, the test accuracy and efficiency are improved.

[0015] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic block diagram of the diode leakage current testing circuit according to an embodiment of the present invention; Figure 2 The circuit diagram of the relay matrix module of the diode leakage current test circuit according to an embodiment of this utility model is shown. Figure 3 This is a circuit diagram of the relay drive module of the diode leakage current test circuit according to an embodiment of the present invention. Figure 4 This is a circuit diagram of the I2C adapter for the diode leakage current testing circuit according to an embodiment of the present invention. Figure 5 This is a circuit diagram of the constant current source module of the diode leakage current testing circuit according to an embodiment of the present invention. Figure 6 This is a circuit diagram of the power supply module of the diode leakage current test circuit according to an embodiment of the present invention.

[0017] Figure label: I / V conversion module 100, inverter 200, voltage buffer module 300, relay module 400, first relay 410, second relay 420, relay matrix module 500, relay driver module 600, I2C adapter 700, constant current source module 800, current buffer unit 810, power supply module 900. Detailed Implementation

[0018] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0019] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first," "second," etc., are used in the description, they are only for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0020] In the description of this utility model, unless otherwise explicitly defined, the terms "setting" and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0021] This embodiment discloses a diode leakage current testing circuit. Please refer to... Figures 1 to 3The diode leakage current test circuit includes an I / V conversion module 100, an inverter 200, a voltage buffer module 300, and a relay module 400. The I / V conversion module 100 includes a first operational amplifier chip U1701 and an RC network unit. The first input terminal of the first operational amplifier chip U1701 is connected to the first terminal of the RC network unit, and the output terminal of the first operational amplifier chip U1701 is connected to the second terminal of the RC network unit. The I / V conversion module 100 is used to convert a current signal into a voltage signal. The inverter 200 includes a second operational amplifier chip U1700 and a first resistor R1705. The first terminal of the first resistor R1705 is connected to the first input terminal of the second operational amplifier chip U1700, and the second terminal of the first resistor R1705 is connected to the output terminal of the first operational amplifier chip U1701. The inverter 200 is used to convert a negative voltage into a positive voltage. The voltage buffer module 300 includes a third operational amplifier chip U1702 and a second resistor R1704. The first end of the second resistor R1704 is connected to the first input terminal of the third operational amplifier chip U1702, and the second end of the second resistor R1704 is connected to the output terminal of the second operational amplifier chip U1702. The voltage buffer module 300 is used to stably output voltage. The relay module 400 includes a first relay 410 and a second relay 420. The first relay 410 is connected to the first input terminal of the first operational amplifier chip U1701, and the second relay 420 is connected to the output terminal of the third operational amplifier chip U1702.

[0022] The main function of the I / V conversion module is to convert current signals into voltage signals. In the I / V conversion module 100, the first operational amplifier chip works with the RC network unit to accurately convert a relatively small current into a relatively large voltage value. The inverter 200, through the second operational amplifier chip and the first resistor, converts the negative voltage into a positive voltage, facilitating the forward operation of the voltage buffer module 300. The voltage buffer module 300, through the third operational amplifier chip and the second resistor, buffers the converted voltage signal to ensure stable output voltage. The relay module 400, through the first relay 410, ensures that the current signal is safely and reliably transmitted to the input terminal of the operational amplifier chip, and outputs a stable voltage signal through the second relay 420. The I / V conversion module 100 converts the detected current signal into a voltage signal. After being adjusted and processed by the inverter 200 and the voltage buffer module 300, the voltage signal is finally output stably through the second relay 420, facilitating the acquisition of voltage using a high-precision instrument-grade analog-to-digital converter to complete diode leakage current testing.

[0023] Please refer to Figure 1The RC network unit includes a first capacitor C1705 and a third resistor R1709 connected in parallel. The main function of the first capacitor C1705 is to store charge, smoothing voltage changes in the circuit and reducing the impact of instantaneous voltage fluctuations. The main function of the third resistor R1709 is to provide a voltage divider effect and, together with the first capacitor C1705, form an RC circuit, affecting the charging and discharging speed of the capacitor. When the power is turned on, the capacitor begins to charge. As the voltage gradually increases, the amount of charge stored in the capacitor increases, and the resistance determines the charging speed based on its value. After a period of time, the capacitor voltage tends to stabilize. At this point, the RC network unit forms a stable voltage divider effect, providing a stable voltage for subsequent circuits, thereby enhancing the circuit's anti-interference capability and stability.

[0024] Please refer to Figure 2 The first relay 410 is connected to a relay matrix module 500, which is used for multi-channel testing. The relay matrix module 500 includes multiple third relays connected in parallel, each connected to a light-emitting diode (LED). The first relay 410 switches different test channels by controlling the on / off state of the control circuit, enabling selection and switching of multiple channels. The relay matrix module 500 can meet the testing needs of multiple channels, containing multiple third relays connected in parallel. Each third relay can operate independently, thus enabling access to and isolation of different test points. Each third relay is connected to an LED as an indicator of its operating status, providing a convenient and intuitive understanding of the test status.

[0025] Please refer to Figure 3 The relay matrix module 500 is connected to a relay driver module 600. The relay driver module 600 includes a data conversion chip and a Darlington driver, with the input terminal of the Darlington driver connected to the I / O terminal of the data conversion chip. The relay matrix module 500, through its built-in multiple sets of relays, can connect or disconnect circuits based on external control signals, thereby testing multiple diodes. The data conversion chip in the relay driver module 600 is responsible for converting various control signals output from the microcontroller or other control devices into the electrical signals required to drive the relays; these converted signals are then amplified by the Darlington driver to ensure sufficient current to drive the relays. The relay driver module 600 can effectively control the operating state of the relay matrix module 500, achieving precise control of multiple circuits.

[0026] Please refer to Figure 4The relay driver module 600 is connected to an I2C adapter 700, which includes an I2C isolator and an I2C switch. The I2C isolator is connected to the I2C switch. The relay driver module 600 is used to control the on / off state of the circuit, and the connected I2C adapter 700 further enhances the system's communication capabilities. The I2C isolator in the I2C adapter 700 provides electrical isolation, effectively preventing interference in signal transmission, thereby improving the stability and reliability of communication. The I2C switch is designed to enable flexible connection or disconnection on the I2C bus, controlling the relay by controlling the relay driver module 600.

[0027] Please refer to Figure 5 The diode leakage current test circuit also includes a constant current source module 800, which is equipped with a current buffer unit 810. The constant current source module 800 is used to test the breakdown voltage of the diode. The function of the constant current source module 800 is to provide a stable constant current. The diode conducts when it reaches its breakdown voltage, thus allowing for accurate measurement of its breakdown voltage. The constant current source module 800 outputs a constant current, which is applied to the diode under test. As the voltage gradually increases, the diode breaks down when it reaches its breakdown voltage and switches to a conducting state. The voltage measured at this point is the breakdown voltage of the diode. This process allows for accurate evaluation of the diode's breakdown voltage performance.

[0028] Please refer to Figure 6 The diode leakage current test circuit also includes a power supply module 900, which includes a power management chip U1100. The power supply module 900 provides power. The power management chip U1100 is an ADR130AUJZ-REEL7 integrated circuit; it is surface-mounted using SMT technology, has 6 pins, and operates at 2V~18V. The power supply module 900 is responsible for providing stable power support to the entire leakage current test circuit. The power management chip U1100 can efficiently regulate and control the power output, ensuring that the power supplied to the test circuit is stable and meets the test requirements.

[0029] Please refer to Figure 1The first operational amplifier chip, U1701, is an integrated circuit of model ADA4530-1ARZ-R7. It is surface-mounted using SMT (Surface Mount Technology), and its operating voltage is 4.5V~16V with a single power supply and ±2.25V~±8V with dual power supplies. The second and third operational amplifier chips, U1700 and U1702, are both integrated circuits of model AD8065ARTZ-REEL. They are also surface-mounted using SMT technology, have 5 pins, operate at 5-24V, and are 145MHz FastFET operational amplifiers. The use of SMT technology for surface-mounting the main circuit components achieves high-density integration, meeting the miniaturization requirements of the test board; the use of lower-cost circuit components reduces the overall cost of the solution.

[0030] Both the first relay 410 and the second relay 420 are AGQ200A4H double-pole double-throw relays, which are installed using SMT. The contact type is double-pole double-throw, the coil voltage is 4.5V, and the rated current is 2A.

[0031] This embodiment also discloses a diode testing device, including the diode leakage current testing circuit described above.

[0032] During testing, multiple diodes are placed, and their test points are connected to a relay matrix module 500. The other end of the relay matrix module 500 is connected to a constant current source module 800 and an I / V conversion module 100. The relay matrix module 500 sequentially switches the diodes to the constant current source module 800 to test their breakdown voltage. After testing the breakdown voltage, the relay matrix module 500 then sequentially switches to the I / V conversion module 100 to test the leakage current. The I / V conversion module 100 converts the detected current signal into a voltage signal. This voltage signal is then processed by an inverter 200 and a voltage buffer module 300 before being stably output through a second relay 420. A high-precision instrument-grade analog-to-digital converter is used to acquire the voltage, thus completing the diode leakage current test. Separating the analog and digital circuits ensures stable and accurate testing, reduces interference, minimizes errors, and improves testing accuracy and efficiency.

[0033] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A diode leakage current test circuit, comprising: include: I / V conversion module (100), the I / V conversion module (100) includes a first operational amplifier chip and an RC network unit, the first input terminal of the first operational amplifier chip is connected to the first terminal of the RC network unit, the output terminal of the first operational amplifier chip is connected to the second terminal of the RC network unit, the I / V conversion module (100) is used to convert current signals into voltage signals; An inverter (200) includes a second operational amplifier chip and a first resistor. The first end of the first resistor is connected to the first input terminal of the second operational amplifier chip, and the second end of the first resistor is connected to the output terminal of the first operational amplifier chip. The inverter (200) is used to convert a negative voltage into a positive voltage. A voltage buffer module (300) includes a third operational amplifier chip and a second resistor. The first end of the second resistor is connected to the first input terminal of the third operational amplifier chip, and the second end of the second resistor is connected to the output terminal of the second operational amplifier chip. The voltage buffer module (300) is used to stably output voltage. The relay module (400) includes a first relay (410) and a second relay (420). The first relay (410) is connected to the first input terminal of the first operational amplifier chip, and the second relay (420) is connected to the output terminal of the third operational amplifier chip.

2. The diode leakage current test circuit of claim 1, wherein, The RC network unit includes a first capacitor and a third resistor connected in parallel.

3. The diode leakage current test circuit of claim 1, wherein, The first relay (410) is connected to a relay matrix module (500), which is used for multi-channel testing.

4. The diode leakage current test circuit of claim 3, wherein, The relay matrix module (500) includes multiple third relays connected in parallel, and each third relay is connected to a light-emitting diode.

5. The diode leakage current testing circuit according to claim 4, characterized in that, The relay matrix module (500) is connected to a relay driver module (600), which includes a data conversion chip and a Darlington driver. The input terminal of the Darlington driver is connected to the I / O terminal of the data conversion chip.

6. The diode leakage current test circuit of claim 5, wherein, The relay drive module (600) is connected to an I2C adapter (700), which includes an I2C isolator and an I2C switch, with the I2C isolator connected to the I2C switch.

7. The diode leakage current test circuit of claim 1, wherein, The diode leakage current test circuit also includes a constant current source module (800), which is provided with a current buffer unit (810). The constant current source module (800) is used to test the breakdown voltage of the diode.

8. The diode leakage current test circuit of claim 1, wherein, The diode leakage current test circuit also includes a power supply module (900), which includes a power management chip and is used to supply power.

9. The diode leakage current test circuit of claim 1, wherein, The first operational amplifier chip uses an integrated circuit with the model number ADA4530-1ARZ-R7.

10. A diode testing apparatus characterized by comprising: Includes the diode leakage current test circuit as described in any one of claims 1 to 9.

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