A Modeling and Application Method for Nonlinear Capacitance Model of DSRD Device

Abstract

This invention relates to a modeling and application method for a nonlinear capacitance model of a DSRD device. The modeling method includes the following steps: decomposing the nonlinear capacitance to establish a current expression for the nonlinear capacitance of the DSRD device; constructing a fitting model for the nonlinear capacitance of the DSRD device based on the current expression and the working principle of the DSRD device; updating the fitting parameters in the fitting model of the nonlinear capacitance of the DSRD device based on the CV curve of the optimal model, thereby obtaining the nonlinear capacitance model of the DSRD device. The nonlinear capacitance model of the DSRD device established by the modeling method provided by this invention can accurately fit the nonlinear capacitance of the DSRD device across the entire voltage range and can achieve accurate simulation of pulse rise time.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor simulation technology, specifically relating to a modeling and application method for a nonlinear capacitance model of a DSRD device. Background Technology

[0002] In recent years, ultrafast high-pulse power technology has been widely used in food processing, medical treatment, water treatment, waste gas treatment, ozone generation, and ion implantation. Switching is a key component of pulse power technology, and its characteristic parameters directly affect the rise time, amplitude, and turn-off time of the output pulse. SiC drift step recovery diodes (DSRDs) are high-power ultrafast semiconductor switches capable of outputting nanosecond-level instantaneous narrow pulse signals due to their advantages such as high switching speed, high repetition frequency, and stackability.

[0003] In 1975, the University of California, Berkeley developed SPICE (Simulation Program for Integrated Circuits Emphasis). With the development of computer technology, SPICE gradually evolved into PSpice software. Using this software, users can conduct numerous circuit simulation experiments to predict circuit performance. Device models serve as a bridge between circuit design and manufacturing processes; the accuracy of the device model directly affects the simulation results. To make the simulation results closer to the actual results, accurate device models must be established, thereby improving design efficiency and reducing design costs.

[0004] Existing DSRD circuit models primarily use a 1N4007 diode to represent the PN structure of the DSRD, multiple series connections to represent the multi-layer stacking of PN junctions, and a fixed parallel capacitor to represent the capacitance effect generated by the PN junction of the DSRD device. However, the pulse rise time obtained by simulation using the above model does not match the actual measurement, making it difficult to ensure the accuracy of the simulation results. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, this invention provides a SPICE modeling method for DSRD devices. The technical problem to be solved by this invention is achieved through the following technical solution:

[0006] The first aspect of the present invention provides a SPICE modeling method for a DSRD device, comprising the following steps:

[0007] Obtain the measured CV curve of the DSRD device;

[0008] The nonlinear capacitor is decomposed, and the current expression of the nonlinear capacitor of the DSRD device is established.

[0009] Based on the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, a nonlinear capacitance model to be fitted for the DSRD device is constructed.

[0010] By changing the model parameters of the nonlinear capacitance model to be fitted by the DSRD device, several model CV curves are obtained through simulation.

[0011] The measured CV curve and the several model CV curves are fitted in mathematical software, and the optimal model CV curve among the several model CV curves is obtained based on the fitting results.

[0012] The fitting parameters in the nonlinear capacitance model of the DSRD device are updated based on the CV curve of the optimal model to obtain the nonlinear capacitance model of the DSRD device.

[0013] In one feasible manner, the DSRD device operates by means of forward injection, reverse extraction, and fast shutdown.

[0014] In one feasible implementation, the current expression for the nonlinear capacitance of the DSRD device is:

[0015]

[0016] Where i is the current of the nonlinear capacitor of the DSRD device, and f(U) is a function of the nonlinear capacitor as a function of the voltage U across it. Let f(V) represent the differential, f(V) be a nonlinear function, and C0 be a linear capacitor.

[0017] In one feasible approach, the nonlinear capacitance model to be fitted for the DSRD device includes: a voltage-controlled current source G. s Voltage source V S3 Resistance R S Voltage-controlled voltage source E3, voltage source V S4 And linear capacitance C0, where,

[0018] The voltage-controlled current source G s The voltage source V S3 and the resistor R S Connected in series to form the first loop;

[0019] The voltage-controlled voltage source E3, the voltage source V S4 It is connected in series with the linear capacitor C0 to form a second circuit;

[0020] Both the first circuit and the first circuit are grounded.

[0021] In one feasible manner, the voltage-controlled current source G sThe control voltage is the voltage across the DSRD device, and the voltage-controlled current source G... s The output current is the nonlinear function f(V);

[0022] The voltage source V S3 and the voltage source V S4 The voltage values ​​are all 0;

[0023] The output voltage and input voltage of the voltage-controlled voltage source E3 are both the voltages across the DSRD device;

[0024] The resistor R S This is used to ensure the convergence of the nonlinear capacitance model of the DSRD device during the simulation process.

[0025] In one feasible manner, the current in the first loop is I1 = f(V);

[0026] The current in the second circuit

[0027] In one feasible approach, the model parameter is a linear capacitance C0;

[0028] The parameters to be fitted are the linear capacitance C0 and the nonlinear function f(V).

[0029] In one feasible approach, the units of the linear capacitance C0 are the same as those of the capacitance in the measured CV curve of the DSRD device.

[0030] A second aspect of the present invention provides a method for applying a nonlinear capacitance model of a DSRD device, comprising the following steps:

[0031] Based on the nonlinear capacitance model of the DSRD device, the equivalent current source G of the nonlinear capacitance of the DSRD device is obtained. c The nonlinear capacitance model of the DSRD device is established using the modeling method for the nonlinear capacitance model of the DSRD device provided in the first aspect of the present invention.

[0032] Based on the nonlinear capacitive equivalent current source G c Construct the equivalent circuit model of the DSRD device.

[0033] In one feasible embodiment, the equivalent circuit model of the DSRD device includes: a resistor R, an inductor L, diodes D1, D2, and D3, and a nonlinear capacitor equivalent current source G. c ,in,

[0034] One end of the resistor R serves as the negative terminal of the equivalent circuit model, and the other end is connected to the negative terminal of the diode D1 through the inductor L.

[0035] The positive terminal of diode D1 is connected to the negative terminal of diode D2;

[0036] The positive terminal of diode D2 is connected to the negative terminal of diode D3;

[0037] The positive terminal of diode D3 serves as the positive terminal of the equivalent circuit model;

[0038] The nonlinear capacitive equivalent current source G c It is connected between the positive terminal of diode D3 and the negative terminal of diode D1;

[0039] The nonlinear capacitive equivalent current source G c The value is the product of the current I1 in the first loop and the current I2 in the second loop in the nonlinear capacitance model of the DSRD device.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] The modeling method for the nonlinear capacitance model of the DSRD device of this invention involves decomposing the nonlinear capacitance to establish a current expression for the nonlinear capacitance of the DSRD device. Based on the current expression of the nonlinear capacitance and the working principle of the DSRD device, a model to be fitted for the nonlinear capacitance of the DSRD device is constructed. The nonlinear capacitance model of the DSRD device is obtained by updating the fitting parameters in the model to be fitted. The nonlinear capacitance model of the DSRD device established by the modeling method of this invention can accurately fit the nonlinear capacitance of the DSRD device across the entire voltage range. It is applicable to DSRD devices with different structures and areas, has fewer model parameters, is easy to adjust, and reduces the complexity of parameter extraction. This nonlinear capacitance model of the DSRD device enables accurate simulation of pulse rise time. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the DSRD device.

[0043] Figure 2 This is a flowchart illustrating the steps of a modeling method for a nonlinear capacitance model of a DSRD device provided in an embodiment of the present invention.

[0044] Figure 3 This is a measured CV curve of the DSRD device provided in the embodiment of the present invention;

[0045] Figure 4 This is a schematic diagram of the circuit structure of the nonlinear capacitance model to be fitted for the DSRD device provided in the embodiment of the present invention;

[0046] Figure 5This invention provides the optimal model CV curve diagram.

[0047] Figure 6 This is a circuit structure diagram of the equivalent circuit model of the DSRD device provided in the embodiments of the present invention;

[0048] Figure 7 This is a schematic diagram of the circuit structure of the pulse generation circuit provided in an embodiment of the present invention;

[0049] Figure 8 This is a simulation result diagram provided by an embodiment of the present invention. Detailed Implementation

[0050] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0051] Please see Figure 1 , Figure 1 This is a schematic diagram of a DSRD device. A DSRD device includes, from bottom to top, a cathode, a heavily doped N-type region (N+), a lightly doped P-type base region (P-base), a heavily doped P-type region (P+), and an anode. The working principle of a DSRD device can be divided into three stages: forward injection, reverse extraction, and fast turn-off. In the forward injection stage, under the action of the forward pump current, electron-hole pairs are generated at the pn junction of the DSRD device and injected into the P-base to form plasma. In the reverse extraction stage, a reverse current extracts the plasma stored in the P-base. After plasma extraction is complete, the reverse current of the DSRD reaches its maximum value, and then the equilibrium majority carrier holes of the P-base are extracted, and the P-base space charge region expands at a saturation drift velocity. In the fast turn-off stage, the P-base space charge region is fully established, and the device turns off rapidly, generating an ultrafast pulse on the load. Based on the working principle of the DSRD device, it can be seen that the DSRD is a strongly nonlinear semiconductor device, and its junction capacitance C during operation... j It will vary with the voltage V across the device. DSRD The capacitance increases rapidly, then decreases slowly, exhibiting strong nonlinearity. However, the parallel capacitor in existing DSRD circuit models cannot accurately simulate the nonlinear capacitance of DSRD devices, resulting in low accuracy in simulation results. Therefore, this embodiment analyzes the working principle of DSRD devices and proposes a modeling method for the nonlinear capacitance of DSRD devices to establish a model that can accurately simulate the nonlinear capacitance of DSRD devices.

[0052] Please see Figure 2 , Figure 2This is a flowchart illustrating the steps of a modeling method for a nonlinear capacitance model of a DSRD device according to an embodiment of the present invention. The modeling method for a nonlinear capacitance model of a DSRD device provided in this embodiment includes the following steps:

[0053] S1: Obtain the measured CV curve of the DSRD device.

[0054] Specifically, the junction capacitance C of the DSRD device is obtained using a semiconductor power analyzer B1505A. j The data showing the change in voltage across the terminals, divided by the reference capacitor C. j0 The normalized capacitance C is obtained. j / C j0 Construct the CV curve. For example... Figure 3 As shown, Figure 3 This is a measured CV curve of the DSRD device provided in this embodiment of the invention. In this embodiment, the reference capacitor C... j0 =31pF, from Figure 3 It can be seen that the junction capacitance C of the DSRD device j With the voltage V across the device DSRD The increase of first decreases rapidly and then decreases slowly, exhibiting a strong nonlinearity.

[0055] S2: Decompose the nonlinear capacitor and establish the current expression of the nonlinear capacitor of the DSRD device.

[0056] Specifically, the characteristics of a nonlinear capacitor are directly related to those of a linear capacitor; the current-voltage characteristic satisfied by a linear capacitor is... When the capacitor is a nonlinear capacitor, the expression for the change of the nonlinear capacitor with the voltage U across its terminals is C = f(U), and the current-voltage characteristic of the nonlinear capacitor is: Decomposing f(U) such that f(U) = C0 × f(V), where C0 is the linear capacitance and f(V) is a nonlinear function, the current-voltage characteristic of the nonlinear capacitor can be expressed as: Therefore, based on the relationship between nonlinear and linear capacitances, the nonlinear capacitance can be decomposed into the product of a linear capacitance and a nonlinear function. Thus, the current expression for the nonlinear capacitance of the DSRD device is:

[0057]

[0058] Where i is the current of the nonlinear capacitor in the DSRD device, and f(U) is the function of the nonlinear capacitor as a function of the voltage U across it. Let f(V) represent the differential, f(V) be a nonlinear function, and C0 be a linear capacitor.

[0059] S3: Based on the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, construct the nonlinear capacitance model to be fitted for the DSRD device.

[0060] Specifically, the working principle of a DSRD device includes forward injection, reverse extraction, and fast turn-off. Combining the working principle of the DSRD device and the current expression of its nonlinear capacitor, where the nonlinear function f(V) is realized through a voltage-controlled current source and the differentiation process is achieved through a linear capacitor, this embodiment designs a nonlinear capacitor model to be fitted to the DSRD device based on its working principle in the three stages of forward injection, reverse extraction, and fast turn-off. This model simulates the working process of the DSRD device in these three stages using circuit representation. Please refer to [link to relevant documentation]. Figure 4 , Figure 4 This is a schematic diagram of the circuit structure of the nonlinear capacitance fitting model of the DSRD device provided in this embodiment of the invention. The nonlinear capacitance fitting model of the DSRD device provided in this embodiment includes: a voltage-controlled current source G. s Voltage source V S3 Resistance R S Voltage-controlled voltage source E3, voltage source V S4 And linear capacitor C0. Wherein, voltage-controlled current source G s Voltage source V S3 and resistance R S The first circuit is formed by connecting the voltage-controlled voltage source E3 and the voltage source V in series. S4 It is connected in series with the linear capacitor C0 to form a second circuit. Both the first and second circuits are grounded.

[0061] Specifically, the voltage-controlled current source G s The control voltage is the voltage across the DSRD device, and the voltage-controlled current source G... s The output current of the voltage source V is a nonlinear function f(V). S3 and voltage source V S4 The voltage values ​​are all 0. The output and input voltages of the voltage-controlled voltage source E3 are both the voltages across the DSRD device. Resistor R S This is used to ensure the convergence of the nonlinear capacitance equivalent model of the DSRD device during the simulation process.

[0062] In this embodiment, V S3 Used to detect the current in the first circuit. V S4 Used to detect the current in the second circuit. Due to the voltage-controlled current source G s The output current is a nonlinear function f(V), therefore, the current in the first circuit is I1 = f(V). The output and input voltages of the voltage-controlled voltage source E3 are both the voltages across the DSRD device; therefore, the current in the second circuit is... The current of the DSRD device Therefore, the nonlinear capacitance characteristics of the DSRD device can be expressed by the currents in the first and second loops in the nonlinear capacitance model to be fitted.

[0063] S4: Change the model parameters of the nonlinear capacitance model to be fitted by the DSRD device, and obtain several model CV curves through simulation.

[0064] Specifically, the model parameter is the linear capacitance C0. The parameters to be fitted are the linear capacitance C0 and the nonlinear function f(V). Simulations are performed using the nonlinear capacitance model of the DSRD device, and the value of the linear capacitance C0 is varied to obtain several model CV curves. The unit of the linear capacitance C0 is the same as the unit of capacitance in the measured CV curve of the DSRD device. For example, the unit of Cj in the measured CV curve is picofarad (pF), therefore, the unit of the linear capacitance C0 is also picofarad (pF).

[0065] S5: Fit the measured CV curve and several model CV curves in the analysis software, and obtain the best model CV curve among several model CV curves based on the fitting results.

[0066] Specifically, in mathematical software such as MATLAB, the measured CV curve and several model CV curves are decomposed and fitted multiple times. The model CV curve that best matches the measured CV curve is selected as the optimal model CV curve. For example, using an inverse proportional function for fitting better reflects the changing law of capacitance and achieves higher fitting accuracy. The optimal model CV curve obtained is shown below. Figure 5 As shown.

[0067] S6: Update the fitting parameters in the nonlinear capacitance model of the DSRD device based on the CV curve of the best model to obtain the nonlinear capacitance model of the DSRD device.

[0068] Specifically, based on the optimal model CV curve, the linear capacitance C0 and the nonlinear function f(V) in the nonlinear capacitance model to be fitted to the DSRD device are updated. The updated nonlinear capacitance model to be fitted to the DSRD device is the nonlinear capacitance model of the DSRD device. For example, as shown... Figure 5 The optimal model CV curve shows a linear capacitance C0 = 0.6 pF and a nonlinear function f(V) = 18.2 × V. -0.4 Depending on the DSRD device being simulated, the model parameters (linear capacitance C0) in the nonlinear capacitance model to be fitted can be changed.

[0069] Furthermore, by implementing the nonlinear capacitance model of the DSRD device obtained in step S6 using the PSpice language, a nonlinear capacitance SPICE sub-circuit model module can be obtained that can be directly called in the DSRD SPICE model. When modeling DSRDs with different structures, only the corresponding parameters need to be adjusted. The specific PSpice language is as follows:

[0070] .subckt G c 9 20

[0071] .param c0=0.6pF,rs=1Ω

[0072] .func gg(x){PWR(x,0.4)}

[0073] gs 40 0value={18.2 / (gg(v(20,9)))}

[0074] vs3 40 41 0

[0075] rs 41 0{rs}

[0076] e3 42 0value={v(9,20)}

[0077] vs4 42 43 0

[0078] c0 43 0{c0}

[0079] gc 9 20value={i(vs4)*i(vs3)}.

[0080] Specifically, 0, 40, 41, 42, and 43 are all... Figure 4 The circuit nodes 9 and 20 in the nonlinear capacitance model of the DSRD device shown are... Figure 6 The circuit nodes in the equivalent circuit model of the DSRD device shown.

[0081] The modeling method provided in this embodiment establishes a nonlinear capacitor model of the DSRD device with linear capacitance C0 as the model parameter. The model has fewer parameters, which can improve the fitting accuracy while reducing the fitting difficulty, thereby improving the accuracy of DSRDSPICE simulation. In addition, the SPICE code for DSRD nonlinear capacitors with different structures and areas has a high degree of repeatability, forming a nonlinear capacitor sub-circuit model that can be called repeatedly.

[0082] This embodiment also provides a method for applying the nonlinear capacitance model of a DSRD device, including the following steps:

[0083] Step 1: Based on the nonlinear capacitance model of the DSRD device, obtain the equivalent current source G of the nonlinear capacitance of the DSRD device. c The nonlinear capacitance model of the DSRD device is established based on the modeling method of the nonlinear capacitance model of the DSRD device provided in this embodiment.

[0084] Step 2: Based on the nonlinear capacitor equivalent current source G c Construct the equivalent circuit model of the DSRD device.

[0085] like Figure 6 As shown, Figure 6 This is a circuit structure diagram of the equivalent circuit model of the DSRD device provided in this embodiment of the invention. The equivalent circuit model of the DSRD device provided in this embodiment includes: resistor R, inductor L, diode D1, diode D2, diode D3, and nonlinear capacitor equivalent current source G. c In this circuit model, one end of resistor R serves as the negative terminal, and the other end is connected to the negative terminal of diode D1 through inductor L. The positive terminal of diode D1 is connected to the negative terminal of diode D2. The positive terminal of diode D2 is connected to the negative terminal of diode D3. The positive terminal of diode D3 serves as the positive terminal of the equivalent circuit model. The nonlinear capacitor equivalent current source G... c It is connected between the positive terminal of diode D3 and the negative terminal of diode D1. The nonlinear capacitor equivalent current source G c The value is the product of the current I1 in the first loop and the current I2 in the second loop in the nonlinear capacitance model of the DSRD device. Diodes D1, D2, and D3 are all 1N4007 diodes to simulate the multilayer PN structure of the DSRD. L is used to simulate the parasitic inductance of the device, typically within 10nH. Resistor R is used to simulate the resistive heating effect during DSRD operation, typically 1Ω.

[0086] Substituting the equivalent circuit model of the DSRD device obtained in this embodiment into the pulse generation circuit, the dynamic characteristics are simulated and verified, such as... Figure 7 As shown, Figure 7 This is a schematic diagram of the circuit structure of the pulse generating circuit provided in an embodiment of the present invention. The pulse generating circuit includes a MOS transistor, capacitors C1, C2, and C3, inductors L1, L2, and L3, and a resistor R. L With resistor R1, the equivalent circuit model of the DSRD device provided in this embodiment is connected to the pulse generation circuit in the form of a diode. The dynamic characteristics of the equivalent circuit model of the DSRD device are verified through simulation of this pulse generation circuit. The simulation results are as follows: Figure 8 As shown, the equivalent circuit model of the DSRD device provided in this embodiment can predict the rise time of the pulse very accurately.

[0087] The modeling method for the nonlinear capacitance model of the DSRD device provided in this embodiment decomposes the nonlinear capacitance, establishes the current expression of the nonlinear capacitance of the DSRD device, and constructs a fitting model of the nonlinear capacitance of the DSRD device based on the current expression of the nonlinear capacitance and the working principle of the DSRD device. The nonlinear capacitance model of the DSRD device is obtained by updating the fitting parameters in the fitting model. The nonlinear capacitance model of the DSRD device established by the modeling method provided in this embodiment can accurately fit the nonlinear capacitance of the DSRD device across the entire voltage range. It is applicable to DSRD devices with different structures and areas, has fewer model parameters, is easy to adjust, and reduces the complexity of parameter extraction. This nonlinear capacitance model of the DSRD device enables accurate simulation of pulse rise time.

[0088] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A modeling method for the nonlinear capacitance model of a DSRD device, characterized in that, Includes the following steps: Obtain the measured CV curve of the DSRD device; The nonlinear capacitor is decomposed, and the current expression of the nonlinear capacitor of the DSRD device is established. Based on the current expression of the nonlinear capacitance of the DSRD device and the working principle of the DSRD device, a nonlinear capacitance model to be fitted for the DSRD device is constructed. The nonlinear capacitance model to be fitted for the DSRD device includes: a voltage-controlled current source Gs, a voltage source VS3, a resistor RS, a voltage-controlled voltage source E3, a voltage source VS4, and a linear capacitor. ,in, The voltage-controlled current source Gs, the voltage source VS3, and the resistor RS are connected in series to form a first circuit; The voltage-controlled voltage source E3, the voltage source VS4, and the linear capacitor Connected in series to form a second circuit; Both the first circuit and the second circuit are grounded; Current in the first circuit ; The current in the second circuit ; in, It is a nonlinear function. To represent the differential; The control voltage of the voltage-controlled current source Gs is the voltage across the DSRD device, and the output current of the voltage-controlled current source Gs is the nonlinear function. The voltage values ​​of voltage sources VS3 and VS4 are both 0; The output voltage and input voltage of the voltage-controlled voltage source E3 are both the voltages across the DSRD device; The resistor RS is used to ensure the convergence of the nonlinear capacitance model of the DSRD device during the simulation process; By changing the model parameters of the nonlinear capacitance model to be fitted by the DSRD device, several model CV curves were obtained through simulation. The model parameters are linear capacitance. ; The measured CV curve and the several model CV curves are fitted in mathematical software, and the optimal model CV curve among the several model CV curves is obtained based on the fitting results. The fitting parameters in the nonlinear capacitance model of the DSRD device are updated based on the optimal model CV curve to obtain the nonlinear capacitance model of the DSRD device. The fitting parameters are linear capacitance parameters. and nonlinear functions .

2. The modeling method for the nonlinear capacitance model of a DSRD device according to claim 1, characterized in that, The working principle of the DSRD device includes: forward injection, reverse extraction, and fast shutdown.

3. The modeling method for the nonlinear capacitance model of a DSRD device according to claim 2, characterized in that, The current expression for the nonlinear capacitor of the DSRD device is as follows: ； in, The current is the nonlinear capacitor of the DSRD device. The capacitance is a function of the nonlinear capacitance as a function of the voltage U across it. To represent the differential, It is a nonlinear function. It is a linear capacitor.

4. The modeling method for the nonlinear capacitance model of a DSRD device according to claim 1, characterized in that, The linear capacitor The units are the same as the units of capacitance in the measured CV curve of the DSRD device.

5. A method for applying a nonlinear capacitance model of a DSRD device, characterized in that, Includes the following steps: Based on the nonlinear capacitance model of the DSRD device, the equivalent current source G of the nonlinear capacitance of the DSRD device is obtained. c The nonlinear capacitance model of the DSRD device is established using the modeling method for the nonlinear capacitance model of the DSRD device according to any one of claims 1 to 4. Based on the nonlinear capacitive equivalent current source G c Construct the equivalent circuit model of the DSRD device.

6. The application method of the nonlinear capacitance model of a DSRD device according to claim 5, characterized in that, The equivalent circuit model of the DSRD device includes: resistor R, inductor L, diode D1, diode D2, diode D3, and nonlinear capacitor equivalent current source G. c ,in, One end of the resistor R serves as the negative terminal of the equivalent circuit model, and the other end is connected to the negative terminal of the diode D1 through the inductor L. The positive terminal of diode D1 is connected to the negative terminal of diode D2; The positive terminal of diode D2 is connected to the negative terminal of diode D3; The positive terminal of diode D3 serves as the positive terminal of the equivalent circuit model; The nonlinear capacitive equivalent current source G c It is connected between the positive terminal of diode D3 and the negative terminal of diode D1; The nonlinear capacitive equivalent current source G c The value is the product of the current I1 in the first loop and the current I2 in the second loop in the nonlinear capacitance model of the DSRD device.

Images