Detection circuit and detection device

Abstract

The utility model provides a detection circuit and a detection device, the detection circuit comprises a detected MOS, a first amplification module and a feedback module, the first amplification module is used for carrying out differential operation based on an adjusting voltage and a feedback voltage, and outputting a test voltage to a grid electrode of a detected MOS tube; the tested MOS tube is conducted in response to the test voltage; the feedback module is used for collecting a test current between a source electrode and a drain electrode of the MOS tube to be tested, converting the test current into a feedback voltage and outputting the feedback voltage to the first amplification module; and the first amplification module is also used for adjusting the adjusting voltage to obtain the test current. Thus, by adding the feedback module, the test current can be converted into the feedback voltage after the MOS tube to be tested is conducted, and the feedback voltage and the input adjusting voltage are subjected to differential operation, so that the nonlinear distortion of the test voltage can be corrected, and the accuracy of detecting the conduction voltage of the MOS tube to be tested is improved; and a foundation is laid for guaranteeing the working safety and stability of the radio frequency circuit.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor devices, in particular to a detection circuit and a detection device. BACKGROUND

[0002] The radio frequency power supply is mainly composed of three types of circuits, i.e., AC-DC conversion circuit, radio frequency circuit and control circuit. The radio frequency circuit is the direct hardware circuit of the radio frequency output. The Metal-Oxide-Semiconductor Field-Effect Transistor (MOS) as a key component of the radio frequency circuit is directly related to the success or failure of the radio frequency output.

[0003] However, due to the influence of preparation process and environmental factors, the turn-on voltage of MOS tubes of different batches will deviate. The slight deviation of the turn-on voltage of the MOS tube will usually cause a large deviation of the drain-source current of the MOS tube when the radio frequency board is working. The radio frequency power supply is a high-frequency power supply. If the radio frequency power is turned on under the condition that the MOS tube is not consistent, the MOS tube will explode and the radio frequency board will be damaged. Therefore, how to improve the accuracy of the detection of the turn-on voltage of the MOS tube to ensure the safety and stability of the radio frequency circuit needs to be solved. CONTENT OF THE INVENTION

[0004] Based on the above needs, the present application provides a detection circuit and a detection device, which can effectively improve the accuracy of the detection of the turn-on voltage of the MOS tube.

[0005] To achieve the above object, the present application provides the following technical scheme:

[0006] According to a first aspect of the embodiment of the present application, a detection circuit is provided, comprising: a measured MOS tube, a first amplification module and a feedback module;

[0007] The first amplification module is configured to perform differential operation based on an adjustment voltage and a feedback voltage, and output a test voltage to the gate of the measured MOS tube.

[0008] The measured MOS tube is turned on in response to the test voltage.

[0009] The feedback module is configured to collect a test current between the source and the drain of the measured MOS tube, and convert the test current into a feedback voltage and output the feedback voltage to the first amplification module.

[0010] The first amplification module is further configured to adjust the adjustment voltage to obtain the test current.

[0011] Optionally, the first amplification module comprises a voltage adjustment unit and a first amplification unit.

[0012] The voltage adjusting unit is configured to receive an initial voltage and adjust the initial voltage to obtain the adjusted voltage in response to an adjusting signal.

[0013] The first amplifying unit is configured to acquire the adjusted voltage and the feedback voltage and perform differential amplification processing on the adjusted voltage and the feedback voltage to obtain the test voltage.

[0014] Optionally, the voltage adjusting unit comprises a first potentiometer, a first capacitor and a first resistor; and the first amplifying unit comprises a first differential amplifier.

[0015] The first end and the second end of the first potentiometer are connected with a first power supply end respectively; the first power supply end is configured to provide the initial voltage; the third end of the first potentiometer is connected with the first end of the first capacitor, the first end of the first resistor and the positive input end of the first differential amplifier respectively; the second end of the first capacitor and the second end of the first resistor are grounded; the negative input end of the first differential amplifier is connected with the output end of the feedback module; and the output end of the first differential amplifier is the output end of the first amplifying module.

[0016] Optionally, the gate of the MOS transistor under test is connected with the output end of the first amplifying module; the source of the MOS transistor under test is connected with the first end of the feedback module; and the drain of the MOS transistor under test is grounded.

[0017] Optionally, the feedback module comprises a current conversion unit and a second amplifying unit.

[0018] The current conversion unit is configured to receive a reference voltage, convert a test current between the source and the drain of the MOS transistor under test into a first voltage based on the reference voltage in the case that the MOS transistor under test is turned on, and output the first voltage to the second amplifying unit.

[0019] The second amplifying unit is configured to perform differential amplification processing based on the first voltage to obtain the feedback voltage and send the feedback voltage to the first amplifying module.

[0020] Optionally, the current conversion unit comprises a second resistor; and the second amplifying unit comprises a third resistor and a second differential amplifier.

[0021] The first end of the second resistor is connected with a second power supply end; the second power supply end is used for providing the reference voltage; the second end of the second resistor is connected with the source of the measured MOS; the first end of the second resistor and the second end of the second resistor are also connected with the positive input end and the negative input end of the second differential amplifier respectively; the output end of the second differential amplifier is connected with the first end of the third resistor; the second end of the third resistor is grounded; and the output end of the second differential amplifier is also connected with the output end of the feedback module.

[0022] Optionally, the second amplification unit further comprises a shottky diode.

[0023] The output end of the second differential amplifier is connected with the output end of the feedback module through the shottky diode.

[0024] Optionally, the detection circuit further comprises a first detection module.

[0025] The first detection module is connected with the output end of the first amplification module, and is used for displaying the test voltage.

[0026] Optionally, the detection circuit further comprises a second detection module.

[0027] The second detection module is connected with the output end of the feedback module, and is used for displaying the feedback voltage.

[0028] According to a second aspect of the embodiment of the present application, a detection device is provided, comprising the detection circuit according to the first aspect of the present application.

[0029] The detection circuit provided in the present application comprises a measured MOS, a first amplification module and a feedback module, wherein the first amplification module is used for performing differential operation based on an adjusting voltage and a feedback voltage, and outputting a test voltage to the measured MOS; the measured MOS is turned on in response to the test voltage; the feedback module is used for collecting a test current between the source and the drain of the measured MOS, and converting the test current into a feedback voltage and outputting the feedback voltage to the first amplification module; and the first amplification module is also used for adjusting the adjusting voltage to obtain the test current. In this way, by adding the feedback module, the test current can be converted into the feedback voltage after the measured MOS is turned on, and the feedback voltage is subjected to differential operation with the input adjusting voltage, so that the non-linear distortion of the test voltage can be corrected, the quality of signal transmission is ensured, and the accuracy of detection of the turn-on voltage of the measured MOS is improved, thereby laying a foundation for ensuring the safety and stability of the radio frequency circuit. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description only belong to the embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0031] Figure 1 A structural schematic diagram of a detection circuit provided by an embodiment of the present application is shown in the figure.

[0032] Figure 2 A structural schematic diagram of another detection circuit provided by an embodiment of the present application is shown in the figure.

[0033] Figure 3 A circuit connection schematic diagram of a detection circuit provided by an embodiment of the present application is shown in the figure.

[0034] Figure 4 A circuit connection schematic diagram of another detection circuit provided by an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0035] The technical solutions of the embodiments of the present application are applicable to the application scenarios of semiconductor devices. By adopting the technical solutions of the embodiments of the present application, the on-voltage of a MOS transistor can be detected, and at least one group of MOS transistors with better consistency can be obtained, so that MOS transistors with better consistency can be used in the same radio frequency circuit, thereby ensuring the safety and stability of the radio frequency circuit.

[0036] At present, the traditional detection circuit for detecting the on-voltage of a MOS transistor has the problem of large error. For example, the constant current source MOS transistor detection circuit, when detecting the measured MOS transistor, the randomness of manual adjustment and the subjectivity of personal judgment will cause large error in the test result, thereby causing large error in the actual detection result.

[0037] Based on this, the present application proposes a detection circuit, which introduces current regulation, takes the current between the source and the drain of the measured MOS transistor and the on-voltage of the gate as debugging variables, takes the voltage converted by the current between the source and the drain as negative feedback, and forms a linear relationship with the on-voltage of the gate, thereby reducing the nonlinear distortion of the detection circuit, improving the linearity and accuracy of the circuit, and further improving the accuracy of the on-voltage test result, thereby providing help for ensuring the safety and stability of the radio frequency circuit.

[0038] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0039] Exemplary device

[0040] Referring to Figure 1 The embodiment of the present application provides a detection circuit, as shown in the figure, which comprises a measured MOS tube 101, a first amplification module 102 and a feedback module 103. Figure 1 The first amplification module 102 is configured to perform differential operation based on the adjustment voltage and the feedback voltage, and output a test voltage to the gate of the measured MOS tube 101.

[0041] The first amplification module 102 is configured to perform differential operation based on the adjustment voltage and the feedback voltage, and output a test voltage to the gate of the measured MOS tube 101.

[0042] The measured MOS tube 101 is turned on in response to the test voltage.

[0043] It should be noted that the measured MOS tube 101 can be an N-type MOS tube or a P-type MOS tube. The description of the present application is described by taking the measured MOS tube as an N-type MOS tube as an example.

[0044] When the first amplification module 102 outputs the test voltage to the measured MOS tube 101, the test voltage is output to the gate of the measured MOS tube 101, and the gate controls the conduction degree between the source and the drain of the measured MOS tube 101. When the test voltage reaches the turn-on voltage, the measured MOS tube 101 is turned on in response to the test voltage, and the current between the source and the drain increases with the increase of the test voltage. When the test voltage reaches the preset voltage, the source and the drain of the measured MOS tube 101 are completely turned on.

[0045] The preset voltage can be determined according to actual measurement. When the test voltage reaches the preset voltage, the source and the drain are completely turned on, that is, the test current reaches the maximum after the test voltage reaches the preset voltage, and the test current no longer continues to increase with the subsequent increase of the test voltage.

[0046] The feedback module 103 is configured to collect the test current between the source and the drain of the measured MOS tube 101, convert the test current into a feedback voltage, and output the feedback voltage to the first amplification module 102.

[0047] Without the feedback module 103, the first amplification module 102 is used to perform gain adjustment on the adjustment voltage, but as the adjustment voltage increases, the gain capability of the first amplification module 102 decreases, that is, the linearity between the input (adjustment voltage) and the output (test voltage) decreases, causing nonlinear distortion of the output. In the scheme of the present application, negative feedback adjustment is introduced, that is, the feedback module 103 is added, and the feedback coefficient of the feedback module is a constant. Therefore, the input (representing the test current) and the output (representing the test voltage) of the negative feedback are in a stable linear relationship, which can correct the nonlinear distortion of the test voltage, thereby improving the accuracy of the detection.

[0048] The first amplification module 102 can also be used to adjust the adjustment voltage to obtain the test current.

[0049] Specifically, the adjustment voltage can be adjusted based on the adjustment signal. By adjusting the adjustment voltage, the test voltage changes, that is, the voltage received by the gate of the measured MOS changes, which is equivalent to the on-voltage of the measured MOS changing. Accordingly, the test current at the measured MOS changes, thereby achieving adjustment of the test current by adjusting the adjustment voltage.

[0050] In implementation, the size of the test current can be determined according to actual needs, which is not limited here. For example, the test current can be 1 mA, and accordingly, the detection circuit provided in the embodiment can obtain the test voltage of the measured MOS when the test current is 1 mA, that is, the on-voltage of the measured MOS when the current between the source and the drain of the measured MOS is 1 mA.

[0051] In the embodiment of the present application, the detection circuit can include a measured MOS, a first amplification module, and a feedback module. The first amplification module is used to perform differential operation based on the adjustment voltage and the feedback voltage and output the test voltage to the measured MOS. The measured MOS is turned on in response to the test voltage. The feedback module is used to collect the test current between the source and the drain of the measured MOS and convert the test current into the feedback voltage and output the feedback voltage to the first amplification module. The first amplification module is also used to adjust the adjustment voltage to obtain the test current. In this way, by adding the feedback module, the test current can be converted into the feedback voltage after the measured MOS is turned on, and the adjustment voltage is inputted to perform differential operation, thereby correcting the nonlinear distortion of the test voltage, ensuring the quality of signal transmission, and improving the accuracy of the on-voltage detection of the measured MOS.

[0052] In practical applications, the test voltages of different MOSFETs under the same test current can be obtained through the detection circuit. MOSFETs with similar test voltages can then be regarded as having high consistency and applied to the same RF circuit, thereby ensuring the safety and stability of the RF circuit operation.

[0053] As an optional implementation method, see [link to implementation details]. Figure 2 and Figure 3 As shown in another embodiment of this application, the first amplification module 102 may include a voltage regulation unit 1021 and a first amplification unit 1022.

[0054] The voltage regulation unit 1021 is used to receive the initial voltage and, in response to the regulation signal, regulate the initial voltage to obtain the regulated voltage.

[0055] The first amplification unit 1022 is used to acquire the regulation voltage and the feedback voltage, and to perform differential amplification on the regulation voltage and the feedback voltage to obtain the test voltage.

[0056] Thus, the voltage adjustment unit 1021 can adjust the voltage based on the initial voltage and the adjustment signal to obtain an adjustable voltage. The adjustment signal can be a signal provided by the user based on testing and adjustment requirements. Based on the adjustment signal, the corresponding adjustable voltage can be obtained. The first amplification unit 1022 performs differential amplification of the signal, effectively enhancing the amplitude of the input signal, making the output signal more pronounced, and thus the obtained test voltage more obvious. Simultaneously, it effectively suppresses common-mode noise and interference, ensuring the accuracy and integrity of signal transmission, laying a structural foundation for improving the accuracy of the detection circuit.

[0057] Specifically, such as Figure 3 As shown, the voltage adjustment unit 1021 may include a first potentiometer P1, a first capacitor C1 and a first resistor R1; the first amplification unit 1022 may include a first differential amplifier U1A.

[0058] In this configuration, the first terminal 1 and the second terminal 2 of the first potentiometer P1 are connected to the first power supply terminal VCC-1, which provides the initial voltage. The third terminal 3 of the first potentiometer P1 is connected to the first terminal of the first capacitor C1, the first terminal of the first resistor R1, and the positive input terminal of the first differential amplifier U1A. The second terminals of the first capacitor C1 and the first resistor R1 are both grounded to GND. The negative input terminal of the first differential amplifier U1A is connected to the output terminal of the feedback module 103. The output terminal of the first differential amplifier U1A is the output terminal of the first amplification module 102.

[0059] In some implementations, such as Figure 3As shown, the first amplification unit 1022 may further include a fourth resistor R4, which is disposed between the output terminal of the first differential amplifier U1A and the output terminal of the first amplification module 102. Thus, the fourth resistor R4 can be used as a current-limiting resistor to protect the MOSFET under test and prevent damage to the MOSFET during testing.

[0060] In implementation, the first potentiometer P1 and the first resistor R1 can form a voltage divider circuit, thereby achieving adjustment of the regulating voltage. The first differential amplifier U1A can have a gain adjustment resistor R. C By adjusting the gain adjustment resistor R C The resistance value can be adjusted to regulate the output amplification factor of the first differential amplifier U1A to meet different gain requirements of users.

[0061] Taking an initial voltage of 15V, a first resistor R1 of 10KΩ, a first capacitor C1 of 0.01F, and a fourth resistor R4 of 10KΩ as an example, when testing the MOSFET, after initial power-on, the first differential amplifier U1A has no negative feedback. Adjusting the first potentiometer P1 until the resistance between its second and third terminals (2 and 3) is nearly 0Ω, it can be considered that +15V is entirely applied to the first resistor R1 and input to the positive input terminal of the first differential amplifier U1A. At this point, the adjustable voltage is +15V. As the resistance between the second and third terminals of the first potentiometer P1 is gradually increased, the first potentiometer P1 and the first resistor R1 form a series voltage divider. The voltage applied to the first resistor R1 gradually decreases, and the voltage input to the positive input terminal of the first differential amplifier U1A gradually decreases, meaning the adjustable voltage gradually decreases from +15V, thus achieving voltage regulation. When the regulated voltage is output to the positive input terminal of the first differential amplifier U1A at a higher voltage value, the differential input voltage of the first differential amplifier U1A is larger, and therefore the test voltage output by the first differential amplifier U1A is also larger.

[0062] It should be noted that the embodiments of this application are only described with the voltage adjustment unit 1021 including the first potentiometer P1 as an example, but this application is not limited to this. In some other embodiments, the voltage adjustment unit 1021 may also include other components, such as the voltage adjustment unit 1021 may include an adjustable resistor, thereby using the adjustable resistor to adjust the voltage.

[0063] As an optional implementation method, see [link to implementation details]. Figure 3 As shown, in another embodiment of this application, the gate g of the MOS transistor under test is connected to the output terminal of the first amplification module 102; the source s of the MOS transistor under test is connected to the first terminal of the feedback module 103; and the drain d of the MOS transistor under test is grounded to GND.

[0064] When the test voltage output from the first amplification module 102 is applied to the gate g of the MOSFET under test, and the test voltage reaches the turn-on voltage, the source s and drain d of the MOSFET under test begin to conduct, and a test current is obtained.

[0065] In practice, the drain d of the MOSFET under test can be grounded through diode N. In this way, the unidirectional conductivity of diode N can be utilized to avoid damage to the detection circuit from reverse voltage, and at the same time, the stability of the detection circuit is improved.

[0066] As an optional implementation method, see [link to implementation details]. Figure 2 and Figure 3 As shown in another embodiment of this application, the feedback module 103 may include a current conversion unit 1031 and a second amplification unit 1032.

[0067] The current conversion unit 1031 is used to receive a reference voltage. When the MOSFET under test is turned on, it converts the test current between the source and drain of the MOSFET under test into a first voltage based on the reference voltage and outputs it to the second amplification unit 1032.

[0068] The second amplification unit 1032 is used to perform differential amplification based on the first voltage to obtain a feedback voltage, and then send it to the first amplification module 102.

[0069] Thus, the current conversion unit 1031 can convert the test current into a voltage, enhancing the linear relationship between the test voltage and the test current and ensuring a more accurate test voltage. The second amplification unit 1032 can differentially amplify the voltage difference characterizing the test current, obtaining a feedback voltage while further improving the stability and anti-interference capability of the detection circuit.

[0070] Specifically, such as Figure 3 As shown, the current conversion unit 1031 may include a second resistor R2; the second amplification unit 1032 may include a third resistor R3 and a second differential amplifier U2A.

[0071] Specifically, the first end of the second resistor R2 is connected to the second power supply terminal VCC-2; the second power supply terminal VCC-2 is used to provide a reference voltage; the second end of the second resistor R2 is connected to the source s of the MOSFET under test; the first end of the second resistor R2 and the second end of the second resistor R2 are also connected to the positive input terminal and the negative input terminal of the second differential amplifier U2A, respectively; the output terminal of the second differential amplifier U2A is connected to the first end of the third resistor R3; the second end of the third resistor R3 is grounded to GND; the output terminal of the second differential amplifier U2A is also connected to the output terminal of the feedback module 103.

[0072] In practice, when the source (s) and drain (d) of the MOSFET under test are conducting, a test current is generated. The maximum value of the test current is the ratio of the reference voltage to the second resistor R2. After the test current is generated, the second resistor R2 converts the test current, so that the test current, after passing through the second resistor R2, forms a voltage value that is input to the positive and negative input terminals of the second differential amplifier for two-stage differential processing. The first end of the third resistor R3 is connected to the output terminal of the second differential amplifier U2A, and the second end is grounded (GND), which can stabilize the circuit.

[0073] Of course, this application is not limited to this; in some embodiments, such as Figure 3 As shown, the second amplification unit 1032 may also include an emitter follower Q; the output of the second differential amplifier U2A is connected to the output of the feedback module 103 through the emitter follower Q.

[0074] In practice, the feedback voltage output by the second differential amplifier U2A is entirely applied to the third resistor R3 and fed into the positive input terminal of the emitter follower Q. The emitter follower Q is also a voltage follower circuit, which can effectively reduce the loss of feedback voltage during transmission. At the same time, it can isolate the circuit on the positive input terminal side of the emitter follower Q from the circuit on the output terminal side of the emitter follower Q, preventing mutual interference between the preceding and following stage circuits, that is, preventing mutual interference between the first amplification module 102 and the feedback module 103.

[0075] In addition, the second amplification unit 1032 may also include a fifth resistor R5 and a second capacitor C2.

[0076] In this circuit, the first terminal of the fifth resistor R5 is connected to both the output terminal of the emitter follower Q and the first terminal of the second capacitor C2; the second terminal of the fifth resistor R5 is grounded (GND); and the second terminal of the second capacitor C2 is grounded. The fifth resistor R5 and the second capacitor C2 serve to stabilize the circuit and filter out interference.

[0077] Thus, the feedback voltage output by the emitter follower Q is entirely applied to the fifth resistor R5 and fed into the negative input terminal of the first differential amplifier U1A, forming a differential input with the positive input terminal of the first differential amplifier U1A, thus creating negative feedback regulation.

[0078] As an optional implementation method, see [link to implementation details]. Figure 4 As shown in another embodiment of this application, the detection circuit may further include a first detection module 104; the first detection module 104 is connected to the output terminal of the first amplification module 102 and is used to display the test voltage.

[0079] In practice, to obtain the test voltage value more intuitively, a first test hole K1 can be set between the gate g of the MOSFET under test and the output terminal of the first amplification module 102. One end of the first test hole K1 is grounded, and the other end is connected to the first detection module 104. The first detection module 104 may include a first digital voltmeter for displaying the voltage value input to the gate g of the MOSFET under test, providing convenience for intuitive and rapid acquisition of the conduction voltage of the MOSFET under test.

[0080] As an optional implementation method, see [link to implementation details]. Figure 4 As shown in another embodiment of this application, the detection circuit may further include a second detection module 105; the second detection module 105 is connected to the output terminal of the feedback module 103 and is used to display the feedback voltage.

[0081] In practice, a second test port K2 can be set at the output terminal of the second differential amplifier U2A. One end of the second test port K2 is grounded to GND, and the other end is connected to the second detection module 105.

[0082] Specifically, the second detection module 105 can also be a second digital voltmeter, used to display the voltage value converted from the current (test current) between the source s and drain d of the MOSFET under test. While realizing the visualization of the feedback voltage, it provides an adjustment basis for obtaining the required test voltage.

[0083] Taking an initial voltage of 15V, a first resistor R1 of 10KΩ, a first capacitor C1 of 0.01F, a fourth resistor R4 of 10KΩ, a second resistor R2 of 2KΩ, and a third resistor R3 of 10KΩ as an example, when testing a MOSFET, the 15V voltage is connected to the first potentiometer P1 and then fed to the positive input terminal of the first differential amplifier U1A. It is differentially amplified with the feedback voltage from the emitter follower Q. The first differential amplifier U1A can effectively enhance the circuit's anti-interference capability and reduce harmonic distortion. The output of the first differential amplifier U1A outputs a test voltage through the fourth resistor R4, and this test voltage is applied to the gate g of the MOSFET under test as the turn-on voltage Ugs of the MOSFET. The first digital voltmeter displays the turn-on voltage Ugs of the MOSFET under test. A test current Ids is generated between the source s and drain d of the MOSFET under test (since the second resistor R2 = 2KΩ and the reference voltage is 10V, Ids has a maximum of 5mA, meaning Ids is adjustable from 0 to 5mA). The test current Ids forms a voltage difference across the second resistor R2, which is input to the positive and negative input terminals of the second differential amplifier U2A for differential operation, converting the test current Ids into a feedback voltage. This feedback voltage, converted from the test current Ids, is displayed in real time on the second digital voltmeter and simultaneously fed into the emitter follower Q. After being output from the emitter follower Q, it is fed back to the negative input terminal of the first differential amplifier U1A, where it is re-differentiated with the output value (adjustable voltage) of the first potentiometer P1.

[0084] After a higher adjustment voltage is applied to the positive input of the first differential amplifier U1A, the differential input of U1A is larger, resulting in a larger test voltage and a larger test current Ids. This increases the voltage across the second resistor R2, meaning the feedback voltage output of the second differential amplifier U2A increases. This feedback voltage returns to the negative input of the first differential amplifier U1A via the emitter follower Q, increasing the voltage at the negative input of U1A. Consequently, the differential voltage between the positive and negative terminals of the first differential amplifier U1A decreases, leading to a decrease in the output voltage of U1A, a decrease in the test voltage, and a decrease in the test current Ids of the MOSFET under test. When the test current Ids decreases, the feedback voltage output of the second differential amplifier U2A decreases, meaning the input to the negative input of the first differential amplifier U1A decreases. This leads to a increase in the differential voltage of the first differential amplifier U1A, an increase in its output voltage, and ultimately, an increase in the test voltage and, consequently, an increase in the test current Ids.

[0085] As can be seen from the above, when the adjustment voltage output by the first potentiometer P1 suddenly increases, due to the introduction of the feedback of the test current Ids, the feedback voltage received by the negative input terminal of the first differential amplifier U1A increases, the differential input of the second differential amplifier U2A becomes more stable, and the output voltage also becomes more stable. The test voltage output by the first amplification module 102 will not increase due to the sudden increase of the adjustment voltage. When the adjustment test current Ids is 1mA, the voltage value of the test voltage is the actual voltage value corresponding to the current between the source s and drain d of the tested MOSFET being 1mA. Since Ids is adjustable between 0 and 5mA, when 1mA < Ids ≤ 5mA, the test voltage of the tested MOSFET is the voltage value corresponding to 1mA < Ids ≤ 5mA, that is, the test current and test voltage of the tested MOSFET correspond one-to-one.

[0086] Based on this, when the required test current is 1mA, the adjustment voltage can be adjusted so that the test current is 1mA. The current between the source (s) and drain (d) of the MOSFET under test corresponds one-to-one with the test voltage. Therefore, the conduction voltage of the MOSFET under test obtained by the detection circuit provided in the embodiments of this application is more accurate, which provides a guarantee for selecting a set of MOSFETs with better consistency.

[0087] Exemplary system

[0088] Accordingly, this application also provides a detection device, which may include a detection circuit as described in any of the above embodiments.

[0089] The detection device provided in this embodiment belongs to the same concept as the detection device provided in the above embodiments of this application. The detection circuit in the detection device has the same functional modules and beneficial effects as the detection circuit provided in any of the above embodiments of this application. Technical details not described in detail in this embodiment can be found in the specific content of the detection circuit provided in the above embodiments of this application, and will not be repeated here.

[0090] The above embodiments illustrate, by way of example, the structure of each part of the detection circuit and detection device proposed in this application, as well as the assembly and connection methods of each part. The implementation of the functions of each part can be performed by referring to the corresponding functions in existing technical solutions, and will not be described in detail in this embodiment.

[0091] It should be noted that the various embodiments provided in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The modules and sub-modules in the device and terminal in the various embodiments of this application can be merged, divided, and deleted according to actual needs.

[0092] It should be understood that the disclosed terminals, devices, and methods can be implemented in other ways, given the several embodiments provided in this application. For example, the terminal embodiments described above are merely illustrative. For instance, the division of modules or sub-modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple sub-modules or modules may be combined or integrated into another module, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0093] The modules or submodules described as separate components may or may not be physically separate. The components that constitute a module or submodule may or may not be physical modules or submodules; that is, they may be located in one place or distributed across multiple network modules or submodules. Some or all of the modules or submodules can be selected to achieve the purpose of this embodiment's solution, depending on actual needs.

[0094] Furthermore, the functional modules or sub-modules in the various embodiments of this application can be integrated into one processing module, or each module or sub-module can exist physically separately, or two or more modules or sub-modules can be integrated into one module. The integrated modules or sub-modules described above can be implemented in hardware or in the form of software functional modules or sub-modules.

[0095] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0096] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A detection circuit, characterized by, The application relates to a MOS transistor testing device. The device comprises a MOS transistor to be tested, a first amplification module and a feedback module. The first amplification module is used for differential operation based on an adjusting voltage and a feedback voltage, and outputs a test voltage to a gate of the MOS transistor to be tested. The MOS transistor to be tested is turned on in response to the test voltage. The feedback module is used for collecting a test current between a source and a drain of the MOS transistor to be tested, converting the test current into the feedback voltage, and outputting the feedback voltage to the first amplification module. The first amplification module is further used for adjusting the adjusting voltage to obtain the test current.

2. The detection circuit of claim 1, wherein, The first amplification module comprises a voltage adjusting unit and a first amplification unit. The voltage adjusting unit is used for receiving an initial voltage, adjusting the initial voltage in response to an adjusting signal, and obtaining the adjusting voltage. The first amplification unit is used for obtaining the adjusting voltage and the feedback voltage, and performing differential amplification processing on the adjusting voltage and the feedback voltage to obtain the test voltage.

3. The detection circuit of claim 2, wherein, The voltage adjusting unit comprises a first potentiometer, a first capacitor and a first resistor. The first end and the second end of the first potentiometer are connected with a first power supply end respectively.

4. The detection circuit of claim 1, wherein, The first power supply end is used for providing the initial voltage.

5. The detection circuit of claim 1, wherein, The third end of the first potentiometer is connected with the first end of the first capacitor, the first end of the first resistor and the positive input end of the first differential amplifier respectively. The second end of the first capacitor and the second end of the first resistor are grounded. The negative input end of the first differential amplifier is connected with the output end of the feedback module.

6. The detection circuit of claim 5, wherein, The output end of the first differential amplifier is the output end of the first amplification module. The gate of the MOS transistor to be tested is connected with the output end of the first amplification module.

7. The detection circuit of claim 6, wherein, The source of the MOS transistor to be tested is connected with the first end of the feedback module. The drain of the MOS transistor to be tested is grounded. The feedback module comprises a current conversion unit and a second amplification unit. The current conversion unit is used for receiving a reference voltage, converting the collected test current between the source and the drain of the MOS transistor to be tested into a first voltage based on the reference voltage when the MOS transistor to be tested is turned on, and outputting the first voltage to the second amplification unit. The second amplification unit is used for performing differential amplification processing based on the first voltage to obtain the feedback voltage, and sending the feedback voltage to the first amplification module. The current conversion unit comprises a second resistor. The second amplification unit comprises a third resistor and a second differential amplifier. The first end of the second resistor is connected with a second power supply end. The second power supply end is used for providing the reference voltage. The second end of the second resistor is connected with the source of the MOS transistor to be tested. The first end and the second end of the second resistor are further connected with the positive input end and the negative input end of the second differential amplifier respectively. The output end of the second differential amplifier is connected with the first end of the third resistor. The second end of the third resistor is grounded. The output end of the second differential amplifier is further connected with the output end of the feedback module. The second amplification unit further comprises a triode. An output terminal of the second differential amplifier is connected with an output terminal of the feedback module through the emitter.

8. The detection circuit of claim 1, wherein, A first detection module is further included; The first detection module is connected with an output terminal of the first amplification module, and is used for displaying the test voltage.

9. The detection circuit of claim 1, wherein, A second detection module is further included; The second detection module is connected with an output terminal of the feedback module, and is used for displaying the feedback voltage.

10. A detection device, characterized in that The detection circuit comprises the detection circuit according to any one of claims 1-9.

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