Current test discharge method and system based on active bleed and segmented control

Abstract

The application provides a current test discharge method and system based on active discharge and segmented control, which comprises the following steps: monitoring the voltage of an energy storage capacitor after chip current test is completed; when the voltage is greater than a first threshold value, entering a constant current discharge mode, in which the gate voltage of a MOS tube is adjusted according to the voltage value, and the discharge current is maintained constant as a set value; the voltage of the energy storage capacitor is continuously monitored, when the voltage is less than the first threshold value and greater than a second threshold value, switching to an exponential decay mode, in which the gate voltage of the MOS tube is continuously adjusted; when the voltage is less than the second threshold value, the MOS tube is turned off, and the discharge process is completed. Through the accurate control of the two stages of constant current discharge and exponential decay, the technical problems of uneven energy release, large transient impact and long discharge time existing in the traditional discharge mode are effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor, in particular to a current test discharging method and system based on active discharge and segmented control. BACKGROUND

[0002] In the field of integrated circuit testing, the rapid and safe discharge of energy storage capacitor after chip current test is a key link to ensure test accuracy and equipment reliability. The existing technology mainly adopts three discharge schemes: passive discharge resistor, mechanical relay switching and single-stage constant current discharge. Although the passive discharge resistor has a simple structure, it is slow in discharging in large-capacity energy storage systems due to the discharge time constant τ=R·C, which seriously affects the test efficiency; the mechanical relay switching method has a short service life (less than 10 5 seconds) and slow response (milliseconds) due to the problem of contact arc, which is difficult to meet the demand of high-frequency test; the single-stage constant current discharge is fast, but it is easy to cause voltage overshoot phenomenon in the discharge process, which may cause potential damage to the chip and test equipment.

[0003] At present, these discharge schemes have two defects: one is the efficiency, the discharge time usually accounts for 30%-50% of the entire test cycle, such as in the 100A current test scene, the discharge time is more than 500 milliseconds, which seriously restricts the test throughput and production efficiency; the second is safety, residual voltage exceeding 5V is easy to trigger subsequent test misjudgment, and arc discharge phenomenon may damage the probe or chip pin, increasing the equipment maintenance cost. With the improvement of integrated circuit test requirements, especially the increasing popularity of high-current and high-speed test scenarios, a more efficient and safer energy storage capacitor discharge method is urgently needed. SUMMARY

[0004] The purpose of the present application is to solve the technical problems of low efficiency, long discharge time and easy damage to the chip in the discharge process of the energy storage capacitor in the chip current test of the prior art.

[0005] In a first aspect of the present application, a current test discharging method based on active discharge and segmented control is provided, comprising:

[0006] After the chip current test is completed, the voltage of the energy storage capacitor is monitored;

[0007] When the voltage is greater than a first threshold value, a constant current discharge mode is entered, and in the constant current discharge mode, the MOS tube gate voltage is adjusted according to the voltage value to maintain the discharge current constant at a set value;

[0008] The voltage of the energy storage capacitor is continuously monitored, and when the voltage is less than the first threshold value and greater than a second threshold value, an exponential decay mode is switched to, and in the exponential decay mode, the MOS tube gate voltage is continuously adjusted;

[0009] The MOS tube is closed when the voltage is less than the second threshold value, and the discharging process is completed.

[0010] Further, the set value is 60%-90% of the test current.

[0011] Further, the MOS tube includes a first MOS tube and a second MOS tube.

[0012] In the constant current discharge mode, the first MOS tube is used for discharging and adjusting the gate voltage thereof.

[0013] When switching to the exponential decay mode, the first MOS tube is closed and the second MOS tube is opened, and the exponential decay discharging is realized by adjusting the gate voltage of the second MOS tube.

[0014] Further, in the constant current discharge mode, the discharge current is monitored in real time by a current sensor, and the gate voltage of the first MOS tube is adjusted according to the monitoring result, forming a closed-loop control.

[0015] Further, in the exponential decay mode, the discharge current I(t) = I0 x ,

[0016] Where I0 is the current value when switching to the exponential decay mode, τ is the time constant, and t is the time elapsed since the exponential decay stage.

[0017] Further, the voltage change rate of the energy storage capacitor is calculated in real time, and the required time constant τ is determined according to the voltage change rate.

[0018] Further, in the exponential decay mode, the gate voltage of the second MOS tube is dynamically adjusted by querying a pre-stored corresponding relationship table of the gate voltage of the second MOS tube and the time constant.

[0019] The second aspect of the present application provides a current test discharging system based on active discharge and stage control, comprising:

[0020] An active discharge module is used to realize a constant current discharge mode and an exponential decay mode.

[0021] A discharge control module is used to receive a discharging instruction, monitor the voltage of an energy storage capacitor, and generate a control signal.

[0022] A current monitoring module is used to monitor the discharge current.

[0023] The discharge control module adjusts the gate voltage of the MOS tube in the active discharge module according to the voltage of the energy storage capacitor and the feedback signal of the current monitoring module, so that the discharging process experiences the constant current discharge mode, the exponential decay mode and the off mode in sequence.

[0024] Further, the active bleed module further comprises a bleed resistor connected in series with the MOS tube.

[0025] Further, the discharge control module stores a mapping table of MOS tube gate voltage and time constant for parameter query in the exponential decay mode.

[0026] Compared with the prior art, the present application has at least the following beneficial effects: through the accurate control of the two stages of constant current discharge and exponential decay, the technical problems of uneven energy release, large transient impact and long discharge time existing in the traditional discharge mode are effectively improved. The constant current discharge mode is adopted in the high voltage interval to quickly discharge a large part of energy, which not only ensures the discharge efficiency, but also avoids the impact of excessive current on the system; when the voltage drops to the first threshold, it is automatically switched to the exponential decay mode, the current is smoothly decayed through the dynamic adjustment of the MOS tube gate voltage, the voltage backflow and electromagnetic interference in the low voltage region are effectively inhibited, the total discharge time is shortened, and the utilization rate of the test equipment is improved. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in 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 as follows. Obviously, the drawings in the following description only constitute the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of the provided drawings.

[0028] Figure 1 for the step schematic diagram of the current test discharge method based on active bleed and segmented control in an embodiment of the present application;

[0029] Figure 2 for the flowchart of the current test discharge method based on active bleed and segmented control in an embodiment of the present application;

[0030] Figure 3 for the module schematic diagram of the current test discharge system based on active bleed and segmented control in an embodiment of the present application.

[0031] Among them, D1-first MOS tube; D2-second MOS tube; R1-first bleed resistor; R2 second bleed resistor; TVS-voltage suppressor; C1-energy storage capacitor. DETAILED DESCRIPTION

[0032] The application will be described in more detail with reference to the drawings, in which the preferred embodiments of the application are shown. It should be understood that modifications can be made to the application as described herein without departing from the spirit of the application, which is defined by the appended claims. The following description is, therefore, not to be taken in a limiting sense.

[0033] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It is also possible in the present disclosure that steps can be executed in different sequence, where this is explicitly indicated, equivalents, or spatial or temporal ordering of different steps and / or repeat levels are implicit. Furthermore, it is to be understood that the use of "a", "an", or "the" in the description indicates there exist one or more of the described elements, and that the use of "comprising" or "including" or "containing" or "consisting of" does not exclude the presence of elements other than those listed. It is also possible in the present disclosure that steps can be executed in different sequence, where this is explicitly indicated, equivalents, or spatial or temporal ordering of different steps and / or repeat levels are implicit.

[0034] The application is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the application are shown. The application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art. In the drawings, like reference numerals refer to like elements throughout.

[0035] Embodiment one

[0036] In a first aspect of the application, there is provided a current test discharge method based on active bleeding and segmented control, please refer to Figures 1-3 , comprising:

[0037] After the chip current test is completed, the voltage of the energy storage capacitor C1 is monitored;

[0038] When the voltage is greater than a first threshold value, a constant current bleeding mode is entered, and in the constant current bleeding mode, the MOS tube gate voltage is adjusted according to the voltage value, and the bleeding current is maintained constant at a set value;

[0039] The voltage of the energy storage capacitor C1 is continuously monitored, and when the voltage is less than the first threshold value and greater than a second threshold value, an exponential decay mode is switched to, and in the exponential decay mode, the MOS tube gate voltage is continuously adjusted;

[0040] When the voltage is less than the second threshold value, the MOS tube is turned off, and the discharge process is completed.

[0041] Specifically, after the chip current test is completed, the system first enters a constant current discharge mode when the voltage is greater than the first threshold value, and a constant discharge current is maintained by dynamically adjusting the gate voltage of the MOS tube to quickly release most of the energy in the energy storage capacitor C1. When the capacitor voltage is less than the first threshold value but greater than the second threshold value, it is automatically switched to an exponential decay mode, and the gate voltage of the MOS tube is continuously adjusted to make the current decay smoothly according to an exponential law, avoiding the backwash phenomenon in the low voltage region. Finally, when the voltage is less than the second threshold value, the MOS tube is turned off to complete the entire discharge process.

[0042] This segmented control method skillfully combines the efficiency of constant current discharge and the smoothness of exponential decay, quickly discharging energy in the high voltage interval, while achieving smooth transition of the current in the low voltage interval, effectively avoiding parasitic oscillation and electromagnetic interference caused by voltage drop. By actively adjusting the gate voltage of the MOS tube instead of the traditional passive discharge or mechanical switching method, not only the discharge speed is improved, the test period is shortened, but also the safety and reliability of the discharge process are ensured.

[0043] Further, the set value is 60%-90% of the test current.

[0044] Further, the first threshold value is 10V-20V; and the second threshold value is 0.5V-2V.

[0045] Specifically, the selection range of the set value is based on the following considerations: when the discharge current is less than 60% of the test current, the discharge time will be significantly prolonged, which cannot meet the test efficiency requirement; and when it exceeds 90%, it may cause the MOS tube to overheat or the voltage to backwash. As a preferred embodiment, the set value can be dynamically adjusted by a programmable current source to adapt to different test current scenarios. For example, under the condition of a 200A test current, the discharge current can be set to 160A (80%), which can ensure the discharge speed and avoid excessive stress on the device. Therefore, by limiting the proportional relationship between the discharge current and the test current, the discharge efficiency is optimized under the premise of ensuring the safety of the discharge. Compared with the existing single-stage constant current discharge, this set range can prevent voltage backwash caused by too fast discharge, and avoid the low efficiency problem of the passive discharge resistor scheme.

[0046] In this embodiment, the first threshold value is set to 10V-20V. When the voltage drops to the set threshold value, the discharge current changes from a constant value to an exponential decay. The second threshold value is set to 0.5V-2V. As a preferred embodiment, the first threshold value is 15V and the second threshold value is 1V, at which point the discharge efficiency and safety reach the best balance. In another embodiment, the threshold value can be adjusted according to different capacitor capacities, for example, for large capacity capacitors, the first threshold value can be set to 18V and the second threshold value can be set to 1.5V.

[0047] Therefore, by setting two precise voltage thresholds, the discharge process is controlled in stages, solving the problem of incomplete discharge or over-discharge in the prior art. Compared with single-stage constant current discharge, this method achieves a discharge speed while avoiding damage to test equipment caused by voltage backflow. Compared with passive bleeding, the discharge time is significantly shortened.

[0048] Further, the MOS tube includes a first MOS tube D1 and a second MOS tube D2.

[0049] In the constant current bleeding mode, the first MOS tube D1 is used for discharging and adjusting its gate voltage.

[0050] When switching to the exponential decay mode, the first MOS tube D1 is turned off and the second MOS tube D2 is turned on, and the exponential decay discharge is achieved by adjusting the gate voltage of the second MOS tube D2.

[0051] Further, in the constant current bleeding mode, the bleeding current is monitored in real time by a current sensor, and the gate voltage of the first MOS tube D1 is adjusted according to the monitoring result to form a closed-loop control.

[0052] Specifically, the current sensor can use a Hall effect sensor or a shunt resistor to monitor the current. In this embodiment, the current sensor uses a Hall effect sensor with model ACS770LCB-200B. As a preferred embodiment, the Hall effect sensor converts the current signal to a voltage signal through an I / V conversion circuit, and inputs the voltage signal to the control unit after being sampled by an ADC. Further, the control unit calculates the gate voltage adjustment amount by a PID algorithm, and drives the first MOS tube D1 gate driver after being converted by a DAC. The closed-loop control loop formed thereby can control the bleeding current fluctuation within ±2%. For example, when the bleeding current deviates due to load changes, the control unit can complete voltage adjustment within 100μs to maintain constant current.

[0053] By introducing a closed-loop control mechanism, the current instability problem caused by element parameter drift or load changes in the traditional open-loop constant current bleeding mode is effectively improved. Compared with the passive bleeding scheme, the closed-loop control improves the current stability and avoids the voltage backflow phenomenon caused by current fluctuations. Compared with the mechanical relay scheme, the electronic adjustment has a millisecond-level response speed and can adapt to high-frequency testing requirements. By accurately maintaining the constant bleeding current, both the discharge efficiency and the potential damage of overcurrent to the test equipment are ensured.

[0054] Further, in the exponential decay mode, the bleeding current I(t)=I0× ,

[0055] where I0 is the current value when switching to the exponential decay mode, τ is the time constant, and t is the time elapsed since the beginning of the exponential decay phase.

[0056] Specifically, the voltage change rate of the energy storage capacitor C1 is calculated in real time, and the required time constant τ is determined according to the voltage change rate. In the exponential decay mode, the relationship between voltage and time follows an exponential function, and the voltage change rate (dV / dt) directly reflects the current discharge rate. By monitoring the actual voltage change rate, it can be determined whether the current time constant τ meets the expectations, which provides a real-time feedback mechanism for the system, allowing it to adjust according to the actual discharge situation.

[0057] Further, in the exponential decay mode, the gate voltage of the second MOS tube D2 is dynamically adjusted by querying a pre-stored corresponding relationship table between the gate voltage of the second MOS tube D2 and the time constant.

[0058] Specifically, the pre-stored corresponding relationship table is established through experiments or simulations. In the implementation process, the corresponding relationship table can be stored in the non-volatile memory of the discharge control module, such as EEPROM or Flash. As a preferred embodiment, the corresponding relationship table is stored in the form of a two-dimensional array, with one dimension being the gate voltage value and the other dimension being the corresponding time constant. In the exponential decay phase, the control module calculates the current required time constant by real-time voltage sampling value, queries the table to obtain the matching gate voltage value, and then outputs the PWM signal to drive the gate of the second MOS tube D2. Thus, the discharge current is accurately attenuated according to the rules.

[0059] Therefore, in the exponential decay phase, the current dV / dt is calculated, and according to the current discharge situation, the required time constant τ is determined; the mapping table is queried to find the gate voltage that can produce the required τ value, and the gate voltage of the MOS tube is adjusted to control the rate of exponential decay. By establishing the mapping relationship between the gate voltage and the time constant, the problem of difficult accurate control of parameters in the traditional exponential decay mode is improved. Since the time constant directly affects the slope of the discharge curve, accurate control can avoid voltage backflush phenomenon, and compared with the fixed parameter attenuation mode, it can dynamically optimize the discharge speed according to the actual working condition.

[0060] Embodiment Two

[0061] This embodiment provides a current test discharge system based on active discharge and phased control, please refer to Figure 3 , comprising:

[0062] An active discharge module is used to implement a constant current discharge mode and an exponential decay mode.

[0063] A discharge control module is used to receive a discharge instruction, monitor the voltage of an energy storage capacitor C1, and generate a control signal.

[0064] a current monitoring module for monitoring the discharge current.

[0065] The discharge control module adjusts the gate voltage of the MOS transistor in the active discharge module according to the voltage of the energy storage capacitor C1 and the feedback signal of the current monitoring module, so that the discharge process experiences the constant current discharge mode, the exponential decay mode and the off mode in turn.

[0066] Specifically, the active discharge module includes a first MOS transistor D1 and a second MOS transistor D2 connected in parallel with the energy storage capacitor C1, the first MOS transistor D1 is used for the constant current discharge mode, and the second MOS transistor D2 is used for the exponential decay mode. In this embodiment, a first discharge resistor R1 and a second discharge resistor R2 are further connected in series with the first MOS transistor D1 and the second MOS transistor D2. The discharge resistor is used to limit the size of the discharge current to prevent the MOS transistor from being damaged by excessive current. The discharge control module stores a mapping table of the gate voltage of the second MOS transistor D2 and the time constant, which is used for parameter query in the exponential decay mode. In the exponential decay mode, the gate voltage of the second MOS transistor D2 is dynamically adjusted by querying the mapping table, so that the discharge current decays according to the exponential law.

[0067] In this embodiment, a transient voltage suppressor TVS is further connected in parallel across the energy storage capacitor C1, which is used to protect the electronic circuit from voltage transients and surges. As a preferred embodiment, the discharge control module can be implemented by a microcontroller or a programmable logic device, which controls each stage of the discharge process through a pre-set program logic. The voltage of the energy storage capacitor C1 can be realized by a high-precision ADC chip to collect the voltage signal in real time. The current monitoring module can be realized by a Hall sensor or a sampling resistor combined with a signal conditioning circuit to monitor the size of the discharge current in real time.

[0068] The segmented control strategy realizes efficient and safe discharge of the energy storage capacitor C1. In the constant current discharge phase, the discharge current is maintained constant through closed-loop control, which improves the discharge speed; in the exponential decay phase, the voltage backflash phenomenon is avoided by dynamically adjusting the gate voltage of the MOS transistor; in the off phase, the discharge loop is timely cut off to ensure the safety and reliability of the discharge process.

[0069] Further, the active discharge module further includes a discharge resistor connected in series with the second MOS transistor D2.

[0070] Specifically, the resistance range of the discharge resistor is usually selected as 1Ω-10Ω, which can effectively limit the peak value of the discharge current and avoid the second MOS tube D2 from bearing excessive current impact at the moment of conduction. As a preferred embodiment, the discharge resistor can be a power metal film resistor, and the rated power thereof should be not less than 5W to meet the long-time working requirement.

[0071] By adding the discharge resistor, the discharge system has multiple technical advantages: first, the discharge resistor and the MOS tube jointly form a composite discharge path, which can share part of the power consumption and reduce the temperature rise of the MOS tube during the constant current discharge stage; second, in the exponential decay mode, the discharge resistor and the dynamic resistance of the MOS tube jointly determine the time constant, so that the discharge curve is more smooth and controllable; finally, when the system is accidentally powered off, the discharge resistor can provide a passive discharge channel to ensure that the residual voltage of the energy storage capacitor C1 can be safely released.

[0072] Further, the discharge control module stores a mapping table of the gate voltage of the second MOS tube D2 and the time constant, which is used for parameter query in the exponential decay mode.

[0073] Specifically, the mapping table stores the time constant parameters corresponding to different gate voltages in the form of discrete data, which is determined by the product of the dynamic resistance of the second MOS tube D2 and the capacitance value of the load capacitor. As a preferred embodiment, the mapping table can be stored in a two-dimensional array structure, wherein the first column is the gate voltage value, and the second column is the time constant measured by experiment.

[0074] By pre-storing the corresponding relationship between the gate voltage and the time constant, the target gate voltage value can be quickly determined in the exponential decay stage, avoiding the processing delay caused by real-time calculation. Compared with the prior art, this method improves the voltage kickback problem when switching the single-stage constant current discharge mode, and by accurately controlling the dynamic parameters of the exponential decay process, both the discharge speed and the potential damage of the over-shock to the test equipment are avoided.

[0075] The following is explained with specific embodiments:

[0076] Implementation scenario: automobile power module test (test current 200A, energy storage capacitor C1 15mF, target discharge time ≤80ms). The system uses Infineon IRFP4668PbF power MOS tube as the discharge switch, the on-resistance of the device is 1.8mΩ, and the maximum drain current is 290A. The discharge resistor is selected as WSHP2818R300FEA type 0.3Ω / 50W resistor and TE CFR100 series 100Ω resistor. The energy storage capacitor C1 is composed of three 2200μF high polymer polymer capacitors in parallel, and the equivalent series resistance is 3mΩ. The control system is realized based on Xilinx Artix-7 FPGA, and is matched with 16-bit ADC for analog-digital conversion, and the sampling rate reaches 1MSPS. The current detection uses a Hall effect sensor ACS770LCB-200B, and the detection accuracy is ±1%.

[0077] The entire discharge process is divided into three stages:

[0078] The first stage is the constant current discharge stage. When the discharge instruction is sent, the discharge control module immediately starts the closed-loop control system and sends the first control signal to the first MOS tube D1. The current sensor monitors the discharge current in real time and sends the feedback signal to the discharge control module. The PID controller dynamically outputs the gate control voltage Vgs according to the current deviation, accurately maintaining the discharge current at 160A. At the same time, the discharge control module continuously monitors the voltage of the energy storage capacitor C1, and automatically switches to the second stage when the voltage drops to 15V.

[0079] The second stage is the exponential decay stage. The discharge control module stops sending the first control signal and starts sending the second control signal to the second MOS tube D2. The system calculates the expected voltage change rate according to the current capacitor voltage, and then queries the pre-stored Vgs-τ mapping table in the discharge control module to obtain the corresponding gate control voltage. By dynamically adjusting the gate voltage, the time constant τ is controlled to achieve smooth decay of the voltage according to the exponential law. When the capacitor voltage drops to 1V, it enters the third stage.

[0080] The third stage is the safe shutdown stage. The discharge control module sets the gate voltage of all MOS tubes to zero, completely shutting down the discharge channel to ensure system safety. Table 1 below is the parameter data of this embodiment. The discharge time is reduced from 520ms to 72ms, an increase of 86%; the peak energy consumption is reduced from 18.5J to 7.2J, a decrease of 61%; and the voltage backflush amplitude is greatly reduced from ±7V to ±0.8V, a decrease of 89%. These data show that the current test discharge method based on active discharge and segmented control used in this embodiment improves the discharge efficiency, reduces the energy consumption, and improves the voltage stability, effectively solving the problems existing in the traditional discharge scheme.

[0081] Table 1

[0082] Parameter Conventional approach This embodiment Amplitude Discharge time 520 ms 72 ms 86%↓ Peak energy consumption 18.5J 7.2J 61%↓ Voltage overshoot amplitude ±7V ±0.8V 89%↓

[0083] The above application of specific examples to illustrate the present invention, is only used to help understand the present invention, and not to limit the present invention. For the skilled in the art to which the present invention belongs, according to the idea of the present invention, can make a number of simple deduction, deformation or replacement.

Claims

1. A current test discharge method based on active bleed and segment control, characterized in that, The application relates to a current test discharging method based on active discharge and segmented control. After the chip current test is completed, the voltage of an energy storage capacitor is monitored; When the voltage is greater than a first threshold value, a constant current discharge mode is entered, in which the MOS tube gate voltage is adjusted according to the voltage to maintain the discharge current constant at a set value; The voltage of the energy storage capacitor is continuously monitored, and when the voltage is less than the first threshold value and greater than a second threshold value, an exponential decay mode is switched to, in which the MOS tube gate voltage is continuously adjusted; When the voltage is less than the second threshold value, the MOS tube is turned off, and the discharging process is completed; The MOS tube comprises a first MOS tube and a second MOS tube; In the constant current discharge mode, the first MOS tube is used for discharging and adjusting the gate voltage thereof; When the exponential decay mode is switched to, the first MOS tube is turned off and the second MOS tube is turned on, and the exponential decay discharging is realized by adjusting the gate voltage of the second MOS tube.

2. The active bleed and segment control based current test discharge method of claim 1, wherein, The set value is 60%-90% of the test current.

3. The active bleed and segment control based current test discharge method of claim 1, wherein, In the constant current discharge mode, the discharge current is monitored in real time through a current sensor, and the gate voltage of the first MOS tube is adjusted according to the monitoring result to form a closed loop control.

4. The active bleed and segment control based current test discharge method of claim 1, wherein, In the exponential decay mode the bleed current I(t) = I0x , Wherein I0 is the current value when the exponential decay mode is switched to, tau is a time constant, and t is the time elapsed since the exponential decay stage starts.

5. The active bleed and segment control based current test discharge method of claim 4, wherein, The voltage change rate of the energy storage capacitor is calculated in real time, and the required time constant tau is determined according to the voltage change rate.

6. The active bleed and segment control based current test discharge method of claim 5, wherein, The gate voltage of the second MOS tube is dynamically adjusted by querying a pre-stored corresponding relation table of the gate voltage of the second MOS tube and the time constant.

7. A current test discharge system based on active bleed and phase control, characterized by, The application discloses a current test discharging method based on active discharge and segmented control. An active discharge module is used for realizing the constant current discharge mode and the exponential decay mode; A discharging control module is used for receiving a discharging instruction, monitoring the voltage of the energy storage capacitor and generating a control signal; A current monitoring module is used for monitoring the discharge current; The discharging control module adjusts the gate voltage of the MOS tube in the active discharge module according to the voltage of the energy storage capacitor and the feedback signal of the current monitoring module, so that the discharging process sequentially experiences the constant current discharge mode, the exponential decay mode and the off mode.

8. The current test discharge system based on active bleed and staging control of claim 7, wherein, The active discharge module further comprises a discharge resistor connected in series with the MOS tube.

9. The active bleed and phased control based current test discharge system as claimed in claim 7, wherein, The discharging control module stores a mapping table of the MOS tube gate voltage and the time constant, which is used for parameter query in the exponential decay mode.

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