Automatic simulation method for single event effect of bipolar band-gap reference circuit

Abstract

The invention discloses an automatic simulation method for a single event effect of a bipolar band-gap reference circuit, which comprises the following steps of: S1, analyzing a circuit netlist file, and extracting transistor names and node information; s2, performing direct-current characteristic simulation on the circuit to obtain a direct-current working point of each transistor, and determining the type of each transistor; s3, establishing a transistor model, and performing transistor-level single event effect simulation to obtain a transistor-level single event effect simulation result; s4, establishing a transient pulse waveform database and a peak value database; s5, screening to obtain a sensitive transistor; s6, selecting one sensitive transistor, and extracting transient pulse data corresponding to the sensitive transistor; s7, modifying the circuit netlist file, and performing circuit-level single-particle transient characteristic simulation to obtain transient characteristic simulation result data; and S8, repeating the steps S6 to S7 to obtain transient characteristic simulation result data corresponding to all the sensitive transistors. According to the invention, the weak link of the simulation device effect is positioned.

Description

Technical Field

[0001] The invention belongs to the field of aerospace technology, and in particular relates to an automatic simulation method for single particle effect of a bipolar bandgap reference circuit. Background Art

[0002] In analog integrated circuits, the bandgap reference structure is used to provide a temperature-independent bias voltage for the circuit, and is one of the basic modules of analog integrated circuits. It is widely used in common electronic products such as LDO, PLL circuits, A / D, D / A, switching power converters, etc. The accuracy and anti-interference ability of the reference source will undoubtedly affect the performance of these products.

[0003] As the feature size of integrated circuits continues to decrease, single-particle effects are increasingly becoming the main factor affecting the working state of space integrated circuits, and single-particle transients have become the main source of integrated circuit soft errors. At present, the accuracy of analog integrated circuits is getting higher and higher, and the speed is getting faster and faster. Even a small voltage disturbance can have a very large impact on the analog circuit, and then cause the entire system to malfunction. Analog circuits are very sensitive to the noise and disturbance introduced by single-particle effects. In analog integrated circuits, the SET effect is the most in need of analysis and reinforcement among all single-particle effects.

[0004] Common methods for analyzing the radiation characteristics of circuits include experiments and simulations. Radiation experiments are not widely used due to their high cost and extremely limited machine time. Circuit-level simulation is a better choice before the final experimental verification. The commonly used method is to model the device-level single-particle transient pulse, inject it into the circuit node for simulation, analyze the impact of the single-particle effect on the circuit characteristics based on the simulation results, and obtain the sensitive nodes in the circuit on this basis. Then, on this basis, anti-single-particle reinforcement design is carried out for the sensitive nodes to improve the circuit's ability to resist radiation.

[0005] For large-scale circuits, all circuit nodes must generally be traversed when searching for sensitive nodes, which is very time-consuming and consumes a lot of computer resources. Even if there are automated methods to implement traversal simulation, it is difficult to escape the huge workload. Therefore, by using certain methods to preliminarily screen sensitive nodes before traversal, the simulation time and computer resources consumed can be greatly reduced. Summary of the invention

[0006] The technology of the present invention solves the problem: overcomes the shortcomings of the prior art and provides an automated simulation method for single particle effects of a bipolar bandgap reference circuit, aiming to locate the weak links of the effects of analog devices.

[0007] In order to solve the above technical problems, the present invention discloses a method for simulating single-particle effects of a bipolar bandgap reference circuit, comprising:

[0008] S1, for the determined bandgap reference circuit, analyzing the circuit netlist file, and extracting transistor names and node information in the bandgap reference circuit;

[0009] S2, performing DC characteristic simulation on the bandgap reference circuit according to the extracted transistor names and node information in the bandgap reference circuit, obtaining the DC operating point of each transistor in the bandgap reference circuit, and determining the type of each transistor;

[0010] S3, establishing a transistor model according to the type of transistor used in the determined bandgap reference circuit, and performing a transistor-level single-particle effect simulation to obtain a transistor-level single-particle effect simulation result;

[0011] S4, establishing a transient pulse waveform database and a peak value database according to the transistor-level single particle effect simulation results;

[0012] S5, based on the peak database, screen and determine the sensitive transistors in the bandgap reference circuit;

[0013] S6, selecting one of the sensitive transistors, and extracting transient pulse data corresponding to the one of the sensitive transistors based on the transient pulse waveform database;

[0014] S7, based on the extracted transient pulse data corresponding to one of the sensitive transistors, modify the circuit netlist file, and perform circuit-level single-particle transient characteristic simulation to obtain transient characteristic simulation result data corresponding to one of the sensitive transistors;

[0015] S8, repeating the above steps S6-S7 to obtain transient characteristic simulation result data corresponding to all sensitive transistors.

[0016] In the above-mentioned single-particle effect automated simulation method for a bipolar bandgap reference circuit, in step S2, a direct current characteristic simulation of the bandgap reference circuit is performed using SPICE simulation software.

[0017] In the above-mentioned bipolar bandgap reference circuit single particle effect automatic simulation method, according to the type of transistor used in the determined bandgap reference circuit, a transistor model is established, and a transistor-level single particle effect simulation is performed to obtain a transistor-level single particle effect simulation result, including:

[0018] According to the determined type of transistor used in the bandgap reference circuit, the transistor model is established using the sde module in the TCAD 3D simulation software, and the characteristic calibration is performed;

[0019] In TCAD 3D simulation software, sdevice is used to simulate the single particle effect at the tube level. The heavy ion parameters that can penetrate the device are selected to obtain the single particle effect simulation results at the transistor level, that is, the transient pulse waveform of each transistor under different collector junction reverse bias voltages.

[0020] In the above-mentioned single-particle effect automated simulation method of the bipolar bandgap reference circuit, the heavy ion parameters include: LET and range; wherein LET = 37.4 MeV·cm 2 / mg, and the range is 30μm.

[0021] In the above-mentioned single-particle effect automatic simulation method of the bipolar bandgap reference circuit, a transient pulse waveform database and a peak value database are established according to the transistor-level single-particle effect simulation results, including:

[0022] According to the simulation results of single particle effect at transistor level, a transient pulse waveform database is established;

[0023] The peak value of the transient pulse waveform is extracted from the established transient pulse waveform database to establish a peak value database.

[0024] In the above-mentioned single-particle effect automatic simulation method of the bipolar bandgap reference circuit, based on the peak database, the sensitive transistors in the bandgap reference circuit are screened and determined, including:

[0025] According to the DC operating point of each transistor in the bandgap reference circuit, the transient current peak value I corresponding to each transistor is obtained from the peak database. max ;

[0026] In the bandgap reference circuit, the collector of each transistor introduces the transient current peak value I corresponding to each transistor. max Based on the circuit structure, the maximum value of the change in the amount of change along its propagation link to the output end is calculated. ref ;

[0027] If the current transistor reaches the maximum value of the change ΔV along its propagation link to the output end ref If it is greater than the set threshold, it is determined that the current transistor is a sensitive transistor.

[0028] In the above-mentioned single event effect automatic simulation method of the bipolar bandgap reference circuit, the threshold is set to 0.1V.

[0029] In the above-mentioned single-particle effect automatic simulation method of the bipolar bandgap reference circuit, one of the sensitive transistors is selected, and based on the transient pulse waveform database, the transient pulse data corresponding to the one of the sensitive transistors is extracted, including:

[0030] One of the sensitive transistors is selected, and transient pulse data corresponding to the one of the sensitive transistors is extracted from a transient pulse waveform database according to a DC operating point of the one of the sensitive transistors.

[0031] In the above-mentioned bipolar bandgap reference circuit single particle effect automatic simulation method, based on the extracted transient pulse data corresponding to one of the sensitive transistors, the circuit netlist file is modified, and a circuit-level single particle transient characteristic simulation is performed to obtain transient characteristic simulation result data corresponding to one of the sensitive transistors, including:

[0032] The extracted transient pulse data corresponding to one of the sensitive transistors is established as a single particle transient current source module;

[0033] Modify the circuit netlist, inject the established single-particle transient current source module into the collector node corresponding to one of the sensitive transistors; use SPICE simulation software to perform circuit-level single-particle transient characteristic simulation, and save the simulation results in a log file;

[0034] The transient characteristic simulation result data corresponding to one of the sensitive transistors is extracted from the log file.

[0035] The above-mentioned single-particle effect automatic simulation method for the bipolar bandgap reference circuit also includes: S9, extracting and comparing the transient waveform peak values ​​of the obtained transient characteristic simulation result data corresponding to all sensitive transistors, and outputting the most sensitive transistor of the bandgap reference circuit.

[0036] The present invention has the following advantages:

[0037] (1) The present invention discloses an automated simulation method for single-particle effects in a bipolar bandgap reference circuit. By preliminarily screening sensitive transistors, the number of transistors that need to be traversed during the actual simulation process is effectively reduced. Compared with the traditional fault injection method that traverses all transistors in the circuit, the simulation time and storage space are effectively reduced, and the efficiency of the circuit-level single-particle transient effect simulation analysis method is greatly improved.

[0038] (2) The present invention discloses an automated simulation method for single particle effects of a bipolar bandgap reference circuit, which can be used for the anti-single particle effect design of different types of analog devices and some digital-analog hybrid devices, including DC / DC, LDO, analog switches, analog comparators, operational amplifiers, reference sources, digital-to-analog converters and other analog devices, overcoming the difficulty of the previous simulation methods not being universal.

[0039] (3) The present invention discloses an automated simulation method for single particle effects of a bipolar bandgap reference circuit, which can be used to replace the heavy ion single particle effect test. The heavy ion single particle effect test cannot accurately locate the weak link of the device to a certain transistor due to its large beam spot area. The present invention can overcome this problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a flow chart of a method for automatic simulation of single-particle effects of a bipolar bandgap reference circuit in an embodiment of the present invention;

[0041] Figure 2 This is a bandgap reference voltage startup simulation diagram in an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of four transistors selected from a bandgap reference source circuit in an embodiment of the present invention;

[0043] Figure 4 It is a schematic diagram of output voltage variation caused by single particle transient effect of transistor Q1 in an embodiment of the present invention;

[0044] Figure 5 It is a schematic diagram of output voltage variation caused by single particle transient effect of transistor Q2 in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0046] One of the core ideas of the present invention is to provide an automated simulation method for single particle effect of bipolar bandgap reference circuit. For a determined bandgap reference circuit, the circuit netlist file is analyzed to extract the transistor name and node information therein, and the SPICE simulator is controlled to simulate the circuit DC characteristics to obtain the DC operating point of each transistor. The transistor to be studied is selected, and the single particle transient waveform is adjusted according to its bias state. The output voltage change ΔV is calculated using the single particle transient pulse peak value. ref Through simplified calculation, the maximum offset value of the reference voltage is obtained, and the screening criteria of the sensitive transistors are determined according to the specific application scenarios. Based on this, the screened sensitive transistors are obtained, and then the simulator is controlled by Python program to perform automatic simulation of single-particle transient effects on the screened transistors. Finally, the waveform is output to obtain the sensitive transistor situation of the entire circuit.

[0047] Reference Figure 1 In this embodiment, the single-particle effect automatic simulation method of the bipolar bandgap reference circuit includes:

[0048] S1, for the determined bandgap reference circuit, the circuit netlist file is analyzed to extract the transistor name and node information in the bandgap reference circuit.

[0049] S2, performing DC characteristic simulation on the bandgap reference circuit according to the extracted transistor names and node information in the bandgap reference circuit, obtaining the DC operating point of each transistor in the bandgap reference circuit, and determining the type of each transistor.

[0050] In this embodiment, SPICE simulation software may be used to simulate the direct current characteristics of the bandgap reference circuit.

[0051] S3, establishing a transistor model according to the type of transistor used in the determined bandgap reference circuit, and performing a transistor-level single particle effect simulation to obtain a transistor-level single particle effect simulation result.

[0052] In this embodiment, first, according to the type of transistor used in the determined bandgap reference circuit, the sde module is used in the TCAD three-dimensional simulation software to establish a transistor model and perform characteristic calibration; then, sdevice is used in the TCAD three-dimensional simulation software to perform tube-level single particle effect simulation, and the heavy ion parameters that can penetrate the device are selected to obtain the transistor-level single particle effect simulation results, that is, the transistor transient pulse waveform of each transistor under different collector junction reverse bias voltages. Among them, the heavy ion parameters mainly include: LET and range; preferably, LET = 37.4MeV·cm 2 / mg, and the range is 30μm.

[0053] S4, based on the transistor-level single particle effect simulation results, establish a transient pulse waveform database and a peak value database.

[0054] In this embodiment, first, a transient pulse waveform database is established according to the transistor-level single particle effect simulation results; then, the peak value of the transient pulse waveform is extracted from the established transient pulse waveform database to establish a peak value database.

[0055] S5, based on the peak database, screen and determine the sensitive transistors in the bandgap reference circuit.

[0056] In this embodiment, first, according to the DC operating point of each transistor in the bandgap reference circuit, the transient current peak value I corresponding to each transistor is obtained from the peak value database. max Then, the transient current peak value I corresponding to each transistor is introduced into the collector of each transistor in the bandgap reference circuit. max Based on the circuit structure, the maximum value of the change in the amount of change along its propagation link to the output end is calculated. ref ; Further, ΔV refCompared with the set threshold, if the maximum value of the change in the current transistor along its propagation link to the output end is ΔV ref If the voltage is greater than a set threshold, the current transistor is determined to be a sensitive transistor. Preferably, the set threshold = 0.1V.

[0057] S6, selecting one of the sensitive transistors, and extracting transient pulse data corresponding to the one of the sensitive transistors based on a transient pulse waveform database.

[0058] In this embodiment, one of the sensitive transistors is selected, and transient pulse data corresponding to the one of the sensitive transistors is extracted from a transient pulse waveform database according to the DC operating point of the one of the sensitive transistors.

[0059] S7, based on the extracted transient pulse data corresponding to one of the sensitive transistors, modify the circuit netlist file, and perform circuit-level single-particle transient characteristic simulation to obtain transient characteristic simulation result data corresponding to one of the sensitive transistors.

[0060] In this embodiment, first, the extracted transient pulse data corresponding to one of the sensitive transistors is established as a single-particle transient current source module; then, the circuit netlist is modified, and the established single-particle transient current source module is injected into the collector node corresponding to one of the sensitive transistors; circuit-level single-particle transient characteristic simulation is performed using SPICE simulation software, and the simulation results are saved in a log file; finally, the transient characteristic simulation result data corresponding to one of the sensitive transistors is extracted from the log file.

[0061] S8, repeating the above steps S6-S7 to obtain transient characteristic simulation result data corresponding to all sensitive transistors.

[0062] S9, extracting and comparing the transient waveform peaks of all the obtained transient characteristic simulation result data corresponding to the sensitive transistors, and outputting the most sensitive transistor of the bandgap reference circuit.

[0063] As can be seen from the above, the method for automatic simulation of single-particle effects of a bipolar bandgap reference circuit according to an embodiment of the present invention mainly includes the following aspects:

[0064] Circuit netlist simulation: mainly realizes the basic principles of circuits.

[0065] Sensitive node screening: It mainly calculates the changes in the final nodes of the circuit caused by the single-particle transients of all transistors, and obtains the transistors whose maximum changes are greater than the specified threshold.

[0066] Circuit single-particle transient characteristics simulation: Based on TCAD simulation, the single-particle effect transient response of the transistor is obtained, and the transient current transient response model is established using Verilog-A. The transient current response model is added to the sensitive transistor in the circuit and simulated.

[0067] Data analysis and processing: Based on the simulation results of the single-particle transient characteristics of the circuit, calculate the impact of different transistors on the change in the final circuit output.

[0068] Based on the above embodiment, a specific example is provided for explanation.

[0069] Example 1

[0070] Taking a bipolar bandgap reference source circuit as an example, the SPICE simulation software is used to simulate the circuit's conventional characteristics, and the output reference voltage is 1.31V. Figure 2 As shown, the four transistors selected are Figure 3 shown.

[0071] According to the bias states of the four selected transistors, based on the double exponential current pulse model, the appropriate single-particle transient pulse is selected and its peak value is taken for subsequent calculations.

[0072] For each selected transistor, a transient pulse peak is introduced at its collector, and the maximum output change ΔV along its propagation link is calculated based on the circuit structure. ref .in:

[0073] The maximum output change ΔV caused by the single-particle transient of transistor Q1 ref(Q1) for:

[0074]

[0075] The maximum output change ΔV caused by the single-particle transient of transistor Q2 ref(Q2) for:

[0076] ΔV ref(Q2) =-I max R4 m4 R2

[0077] The maximum output change ΔV caused by the single-particle transient of transistor Q3 ref(Q3) for:

[0078]

[0079] The maximum output change ΔV caused by the single-particle transient of transistor Q4 ref(Q4) for:

[0080] ΔV ref(Q4) =Imax R2

[0081] Among them, R1~R5 represent the resistance values ​​of resistors R1~R5 respectively, r o,Q2 represents the output resistance of transistor Q2, g m3 represents the transconductance of transistor 3, g m4 represents the transconductance of transistor 4, I max Indicates the maximum current.

[0082] Substitute the numerical value into: ΔV ref(Q1) =0.903V, ΔV ref(Q2) =0.24V,ΔV ref(Q3) =0.068V, ΔV ref(Q4) =0.068V.

[0083] Since this circuit is a bandgap reference source circuit, ΔV is specified ref The transistors with a voltage >0.1V are sensitive transistors. Therefore, the sensitive transistors selected by this circuit are transistor Q1 and transistor Q2.

[0084] Based on Python and SPICE simulation software, the single-particle transient effect is automatically simulated. The single-particle transient waveform at the circuit output caused by transistor Q1 and transistor Q2 is as follows Figures 4-5 As shown, it can be seen that the most sensitive transistor of the bandgap reference circuit is transistor Q1.

[0085] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0086] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A method for automating the simulation of single-particle effects in a bipolar bandgap reference circuit, characterized in that: include: S1, for the determined bandgap reference circuit, analyzing the circuit netlist file, and extracting transistor names and node information in the bandgap reference circuit; S2, performing DC characteristic simulation on the bandgap reference circuit according to the extracted transistor names and node information in the bandgap reference circuit, obtaining the DC operating point of each transistor in the bandgap reference circuit, and determining the type of each transistor; S3, establishing a transistor model according to the type of transistor used in the determined bandgap reference circuit, and performing a transistor-level single-particle effect simulation to obtain a transistor-level single-particle effect simulation result; S4, establishing a transient pulse waveform database and a peak value database according to the transistor-level single particle effect simulation results; S5, based on the peak database, screen and determine the sensitive transistors in the bandgap reference circuit; S6, selecting one of the sensitive transistors, and extracting transient pulse data corresponding to the one of the sensitive transistors based on the transient pulse waveform database; S7, based on the extracted transient pulse data corresponding to one of the sensitive transistors, modify the circuit netlist file, and perform circuit-level single-particle transient characteristic simulation to obtain transient characteristic simulation result data corresponding to one of the sensitive transistors; S8, repeating the above steps S6-S7 to obtain transient characteristic simulation result data corresponding to all sensitive transistors.

2. The method for automating the single-particle effect simulation of a bipolar bandgap reference circuit according to claim 1, characterized in that: In step S2, a direct current characteristic simulation of the bandgap reference circuit is performed using SPICE simulation software.

3. The method for automating the simulation of single-particle effects of a bipolar bandgap reference circuit according to claim 1, characterized in that: According to the type of transistor used in the determined bandgap reference circuit, a transistor model is established, and a tube-level single-particle effect simulation is performed to obtain transistor-level single-particle effect simulation results, including: According to the determined type of transistor used in the bandgap reference circuit, the transistor model is established using the sde module in the TCAD 3D simulation software, and the characteristic calibration is performed; In TCAD 3D simulation software, sdevice is used to simulate the single particle effect at the tube level. The heavy ion parameters that can penetrate the device are selected to obtain the single particle effect simulation results at the transistor level, that is, the transient pulse waveform of each transistor under different collector junction reverse bias voltages.

4. The method for automatic simulation of single-particle effects of a bipolar bandgap reference circuit according to claim 3, characterized in that: Heavy ion parameters, including LET and range; where LET = 37.4 MeV cm 2 / mg, and the range is 30μm.

5. The method for automatic simulation of single-particle effects of bipolar bandgap reference circuit according to claim 1, characterized in that: According to the simulation results of single particle effects at the transistor level, a transient pulse waveform database and a peak value database are established, including: According to the simulation results of single particle effect at transistor level, a transient pulse waveform database is established; The peak value of the transient pulse waveform is extracted from the established transient pulse waveform database to establish a peak value database.

6. The method for automatic simulation of single-particle effects of a bipolar bandgap reference circuit according to claim 1, characterized in that: Based on the peak database, sensitive transistors in the bandgap reference circuit are screened and determined, including: According to the DC operating point of each transistor in the bandgap reference circuit, the transient current peak value I corresponding to each transistor is obtained from the peak database. max ; In the bandgap reference circuit, the collector of each transistor introduces the transient current peak value I corresponding to each transistor. max Based on the circuit structure, the maximum value of the change in the amount of change along its propagation link to the output end is calculated. ref ; If the current transistor reaches the maximum value of the change in the output terminal along its propagation link ΔV ref If it is greater than the set threshold, it is determined that the current transistor is a sensitive transistor.

7. The method for automatic simulation of single-particle effects of a bipolar bandgap reference circuit according to claim 6, characterized in that: Set threshold = 0.1V.

8. The method for automatic simulation of single event effects of bipolar bandgap reference circuit according to claim 1, characterized in that: Selecting one of the sensitive transistors, and extracting transient pulse data corresponding to the one of the sensitive transistors based on a transient pulse waveform database, including: One of the sensitive transistors is selected, and transient pulse data corresponding to the one of the sensitive transistors is extracted from a transient pulse waveform database according to a DC operating point of the one of the sensitive transistors.

9. The method for automatic simulation of single-particle effects of a bipolar bandgap reference circuit according to claim 1, characterized in that: Based on the extracted transient pulse data corresponding to one of the sensitive transistors, the circuit netlist file is modified, and a circuit-level single-particle transient characteristic simulation is performed to obtain transient characteristic simulation result data corresponding to one of the sensitive transistors, including: The extracted transient pulse data corresponding to one of the sensitive transistors is established as a single particle transient current source module; Modify the circuit netlist, inject the established single-particle transient current source module into the collector node corresponding to one of the sensitive transistors; use SPICE simulation software to perform circuit-level single-particle transient characteristic simulation, and save the simulation results in a log file; The transient characteristic simulation result data corresponding to one of the sensitive transistors is extracted from the log file.

10. The method for automatic simulation of single event effects of bipolar bandgap reference circuit according to claim 1, characterized in that: Also includes: S9, extracting and comparing the transient waveform peaks of all the obtained transient characteristic simulation result data corresponding to the sensitive transistors, and outputting the most sensitive transistor of the bandgap reference circuit.

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