JPH06332973A - Circuit simulation device - Google Patents

Abstract

PURPOSE:To shorten the sum total of the analysis time for calculation, etc., and to suppress the increase of the analysis data volume of the analysis result by quickly charging/discharging a capacitor, which has a time constant larger than the signal period handled in a circuit as the circuit simulation object, in this circuit to switch the capacitor to the steady state and performing the characteristic analysis on the time base of the circuit and outputting the analysis result. CONSTITUTION:A circuit simulation device main body 1 consists of a circuit simulator 3, an analysis result output program 4, and a current source circuit adding program 6. The capacitor, which has a time constant larger than the signal period handled in the circuit as the circuit simulation object, in this circuit is quickly charged/discharged by an added current source for quick charging/discharging to shorten the time required for switching to the steady state. Thus, a ratio of the time constant to the signal period handled in the circuit as the object is reduced to reduce the number of analysis points required for characteristic analysis on the time base of the circuit, and not only the sum total of respective analysis times is shortened but also the increase of the analysis data volume is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit simulation device capable of analyzing a circuit in a short time and suppressing an increase in the amount of data obtained as a result of the analysis.

[0002]

2. Description of the Related Art Conventionally, a general-purpose electronic circuit simulation program (hereinafter referred to as a circuit simulator) has been used to analyze a circuit using elements such as resistors, capacitors, inductors, transistors, diodes and voltage / current sources. ing. This circuit simulator takes in the circuit data of the circuit to be simulated and analyzes the circuit characteristics on the time axis of the taken-in circuit.

FIG. 7 is a conceptual diagram showing the configuration of a circuit simulation device using the above circuit simulator. In the figure, reference numeral 1 is a circuit simulation apparatus body including a circuit simulator 3 and an analysis result output program 4 for outputting data analyzed by the circuit simulator 3. Reference numeral 2 denotes a circuit to be analyzed, for example, an AGC circuit, which includes a time constant larger than the cycle of the signal handled by the circuit to be simulated. FIG. 8 shows a circuit diagram which is a target of this circuit analysis.

Next, the operation will be described. Assuming that the minimum period of the signals handled by the circuit to be analyzed 2 is T1, in order to guarantee the analysis accuracy of the circuit simulator 3, the time interval Δt of the analysis on the time axis in the circuit simulator 3 is Δt.
= T1 / n (where n is an integer of 10 or more), and the larger the value of n, the higher the analysis accuracy.

On the other hand, if the maximum period of the signals handled by the target circuit 2 is T2, the analysis time to be simulated is at least one period T2 of this signal, and it is necessary to perform the simulation during this period. As a result, the number of analysis points in the circuit simulator 3 depends on the ratio of the maximum period T2 and the minimum period T1. Further, when the target circuit 2 has a time constant T3 that is larger than the maximum period T2, it is necessary to perform a simulation for at least the period with this time constant.

Assuming that the ratio of the period T3 based on the maximum time constant to the minimum period T1 is m (T3 = mT1), the maximum time is obtained while the analysis accuracy of the signal with the minimum period T1 is guaranteed. In order to simulate the period T3 based on a constant, an analysis point on the time axis having a fineness of T3 = m × n × Δt is required, the analysis time becomes long, and the amount of analysis data obtained as a result of the analysis. Will be huge.

On the other hand, by predicting the voltage value after shifting to a steady state and performing initial setting of the predicted value, a circuit simulation is performed, or a circuit is modeled by an equation at the element level such as a transistor. There is a method of analyzing a target circuit such as an AGC circuit including a time constant larger than the period of a signal to be handled by performing a numerical calculation that is not a circuit simulation.

[0008]

Since the conventional circuit simulation apparatus is configured as described above, in the case where a circuit including a time constant larger than the period of a signal to be handled is accurately analyzed on the time axis. In addition, the number of analysis points increases, the total analysis time for calculation and the like becomes longer, and the amount of analysis data obtained as a result of analysis becomes enormous. There was a problem such as being necessary.

The inventions of claims 1 and 3 are made in order to solve the above-mentioned problems, and shorten the total number of analysis time such as calculation, and at the same time, obtain an analysis result. An object is to obtain a circuit simulation device that can suppress an increase in the amount of data.

According to the second and fourth aspects of the present invention, the total number of analysis times such as calculations can be shortened, an increase in the amount of analysis data obtained as a result of analysis can be suppressed, and circuit analysis can be performed accurately. The purpose is to obtain a circuit simulation device capable of

[0011]

According to a first aspect of the present invention, there is provided a circuit simulation device in which a circuit simulation target circuit having a time constant larger than a signal period handled by a circuit target circuit is provided. The capacitor is charged and discharged at a high speed by an additional current source for high-speed charging and discharging to shift to a steady state, and the characteristic analysis on the time axis of the circuit is performed and the analysis result is output.

According to a second aspect of the present invention, there is provided a circuit simulation device for charging and charging a capacitor in a circuit to be subjected to the circuit simulation, which has a time constant larger than a signal period handled by the circuit to be subjected to the circuit simulation. / Or the high-speed charging / discharging current source added for each discharge route is used to perform high-speed charging / discharging to shift to a steady state, perform characteristic analysis on the time axis of the circuit, and output the analysis result. .

A circuit simulation apparatus according to a third aspect of the present invention is added to a capacitor in a circuit to be subjected to the circuit simulation, which has a time constant larger than a signal period handled by the circuit to be subjected to the circuit simulation. After charging / discharging at high speed by the high-speed charging / discharging current source and shifting to a steady state, the amount of current flowing through the high-speed charging / discharging current source is set to zero, and the characteristic analysis on the time axis of the circuit is performed to obtain the analysis result. It is designed to be output.

According to a fourth aspect of the present invention, there is provided a circuit simulation device for charging and charging a capacitor in a circuit to be subjected to the circuit simulation, which has a time constant larger than a signal period handled by the circuit to be subjected to the circuit simulation. / Or the high-speed charging / discharging current source added for each discharge route is used to perform high-speed charging / discharging to shift to a steady state, and then the amount of current flowing through the high-speed charging / discharging current source is set to zero, and the circuit time axis The above characteristic analysis is performed and the analysis result is output.

[0015]

The circuit simulation device according to the present invention is added to the capacitor in the circuit to be subjected to the circuit simulation, which has a time constant larger than the signal period handled by the circuit to be subjected to the circuit simulation. By shortening the time required for high-speed charging / discharging current source to perform high-speed charging / discharging and transition to a steady state, the ratio of the above signal period and the above time constant handled in the circuit that is the target of circuit simulation can be reduced. The number of analysis points required for the characteristic analysis on the time axis is reduced, the total amount of each analysis time required for the calculation performed for each analysis point is shortened, and the amount of analysis data obtained as a result of the analysis is suppressed.

According to another aspect of the present invention, there is provided a circuit simulation apparatus for a capacitor in a circuit to be subjected to the circuit simulation, which has a time constant larger than a signal period handled by the circuit to be subjected to the circuit simulation.
The above-mentioned signals handled by the circuit that is the object of the circuit simulation by shortening the time required to carry out high-speed charging / discharging by the high-speed charging / discharging current source added for each charging and / or discharging route to shift to the steady state. By reducing the ratio of the cycle and the above time constant to reduce the number of analysis points required for characteristic analysis on the time axis of the circuit, and shortening the total amount of each analysis time required for the calculation performed for each analysis point, The amount of analysis data obtained as a result of is suppressed.

According to a third aspect of the present invention, in the circuit simulation apparatus, after the transition to the steady state, the amount of current flowing through the high-speed charging / discharging current source is set to zero, so that the high-speed circuit to the circuit after the transition to the steady state. The influence of the charging / discharging current source is eliminated, and it becomes possible to perform accurate circuit analysis after shifting to the steady state.

According to a fourth aspect of the present invention, in the circuit simulation apparatus, after the transition to the steady state, the amount of current flowing through the high-speed charging / discharging current source is set to zero, so that the high-speed circuit to the circuit after the transition to the steady state. It eliminates the influence of the charging / discharging current source and enables accurate circuit analysis after shifting to the steady state.

[0019]

【Example】

Embodiment 1 Hereinafter, an embodiment of the invention of claim 1 will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing the circuit simulation apparatus of this embodiment. In the figure, 1 is a circuit simulator (circuit analysis means) 3, an analysis result output program (analysis result output means) 4 for outputting data analyzed by the circuit simulator 3, and a time constant larger than the cycle of a signal to be handled. Current source circuit addition program (current source addition means for high-speed charging / discharging, for charging / discharging) that takes in circuit data having a Current amount control means) 6. 2 is circuit data to be simulated such as a low-pass filter circuit,
It includes a capacitor that has a larger time constant than the period of a normal signal handled by the circuit to be simulated.

FIG. 2 is circuit data showing the target circuit 2 and shows a low pass filter circuit. In the figure,
Q1 and Q2 are transistors, C1 is a capacitor having a relatively large capacitance and a large time constant, and R1 is a capacitor C.
The resistors connected in parallel to 1 and the numbers in the squares indicate the node numbers.

Next, the operation will be described. In this circuit simulation device, a current source circuit having a small internal resistance for forcibly charging / discharging the capacitor C1 of the target circuit 2 when the simulation is performed on the target circuit 2 and the circuit is analyzed. It is added by the addition program 6.

FIG. 3 shows this current source circuit addition program 6
The operation will be described based on this flowchart. In step ST1, a charging / discharging route is set for the input capacitor C1 of the target circuit 2. This set charging / discharging route is the signal line connected to the capacitor C1 at the node 2. In the next step ST2, an ammeter for measuring the original charging / discharging current of the capacitor C1 is installed. In the following step ST3, a current source circuit for adding a current amount proportional to the current value flowing through the ammeter installed in step ST2 to the capacitor C1 through another route is added. That is, a charging / discharging current amount of a constant multiple of the original charging / discharging current value of the capacitor C1 indicated by the installed ammeter is caused to flow into or discharge from the capacitor C1 by another route by the added current source circuit. In step ST4, a proportional constant k is determined which determines how many times the current value originally charged and discharged from the capacitor C1 is flown into or discharged from the capacitor C1 by the current source circuit.

As a result of the series of processing steps ST1 to ST4, the circuit shown in FIG. 4 is generated and output. In FIG. 4, DET1 represents the ammeter installed in step ST2, and CIR1 represents the current source circuit (high-speed charging / discharging current source) added in step ST3.

When the circuit data shown in FIG. 4 is input to the circuit simulator 3 and analyzed on the time axis, the current source circuit CI
Charging / discharging is performed from R1 with a current amount that is k times the original charging / discharging current value, and the capacitor C1 reaches a steady state in about 1 / k times the time. As a result, the number of analysis points on the time axis for analysis is almost 1 / k, and the amount of data obtained as a result of analysis is also reduced. A small amount of memory is used as the memory for storing the data that is this analysis result. You will be able to. Furthermore, it can be expected that the transient response time of the circuit will be almost k times as long.

The current source circuit CIR1 is an ammeter DET.
Although any circuit configuration in which a current proportional to the amount of current indicated by 1 is flown can be used, for example, the circuit simulator 3 used for circuit analysis is generally and often used "SPI".
In the case of “CE”, the ammeter DET1 may be an independent voltage source of 0 V, and the current source circuit CIR1 may be a current control current source.

As described above, a circuit including a capacitor having a time constant larger than the period of a signal to be handled reaches a steady state in a time of about 1 / k, the number of analysis points is reduced, and data is reduced. Although it is possible to suppress the increase in the amount, if the charging / discharging current can be made to flow k times more while making use of the added current source circuit CIR1, the characteristics of the voltage and current after the transition to the steady state will be shown. The state of the circuit is different from the original circuit data shown in 2. Therefore, in order to obtain the same voltage and current characteristics as the original circuit, it is necessary to turn off the current source circuit CIR1 and set the current flowing through the current source circuit CIR1 to zero after reaching the steady state. As a result, the circuit based on the circuit data shown in FIG. 4 exhibits the same characteristics as the circuit based on the original circuit data shown in FIG. 2, and the circuit analysis after shifting to the steady state can be performed accurately. become able to.

However, when the current source circuit CIR1 is turned off, if the current source circuit CIR1 is turned off rapidly in a short time, the influence at that time affects the analysis result. Time) to gradually shift to zero so that the steady state is maintained.

As described above, according to this embodiment,
A current source circuit CIR1 for forcibly charging / discharging the capacitor C1 and an ammeter DET1 for measuring the original charging / discharging current of the capacitor C1 are added, and the charging / discharging of the capacitor C1 is k times the original charging / discharging current. By passing a current, the time constant of the circuit including the capacitor C1 is apparently reduced,
Since the circuit analysis of the circuit including the capacitor C1 having a large time constant can be performed in a short time, the amount of data obtained as a result of the circuit analysis can be reduced, and the data obtained as a result of the analysis is stored. A small amount of memory can be used for the memory.

Embodiment 2 An embodiment of the invention according to claim 2 will be described below with reference to the drawings. FIG. 5 is a conceptual diagram showing the circuit simulation apparatus of the present embodiment. The same or corresponding parts as in FIG. 1 are designated by the same reference numerals and the description thereof is omitted. In the figure, reference numeral 7 denotes a route-specific current source circuit addition program (high-speed charging / discharging current source route addition means) for adding an ammeter or a current source circuit according to the charging current or discharging current route of the capacitor C1.

FIG. 6 shows circuit data to be analyzed, in which a current source and an ammeter are added by the route-specific current source circuit addition program 7.

In the first embodiment, as shown in FIG. 4, the charging / discharging of the capacitor C1 is shared by one ammeter DET1 and one current source circuit CIR1. When charging and discharging are simultaneously performed in different paths, it may be better to set the ammeter and the current source circuit independently of each other. Therefore, in the present embodiment, the charging and discharging routes of the capacitor C1 are separately classified. Set to.

In FIG. 6, DET2 is an ammeter and CIR.
2 is a current source circuit (current source for high-speed charging / discharging) and an ammeter D
A current amount k1 times the current value indicated by ET2 can be passed. Further, DET3 is an ammeter, and CIR3 is a current source circuit (high-speed charging / discharging current source), and a current amount k2 times the current value indicated by the ammeter DET3 can flow.

If the proportional constants k1 and k2 are set to the same value, the response time until the steady state is reached in the original circuit shown in FIG. 2 can be predicted. That is, the response time according to the analysis result of the circuit simulation 3 is approximately k times (k
= K1 = k2) is the response time until the steady state in the original circuit shown in FIG. 2 is reached.

When there are a plurality of charging or discharging routes, an ammeter and a current source circuit as necessary are added to each route.

In this embodiment as well, in order to obtain the same voltage and current characteristics as those of the original circuit, the current source circuit CIR2 and the current source circuit CIR3 are turned off after the steady state is reached. The current flowing through the current source circuit CIR3 is set to zero.

As described above, according to this embodiment,
Since an ammeter and a current source circuit as needed are added to each charging or discharging route, the circuit configuration to be analyzed is complicated and there are a plurality of charging / discharging routes for the capacitor C1. Even in the case of high accuracy, circuit analysis can be performed, and the capacitor C has a large time constant.
It is possible to perform a circuit analysis of a circuit including 1 etc. in a short time, reduce the amount of data obtained as a result of the circuit analysis, and store a small amount of memory in the memory for storing the data obtained as a result of the analysis. Can be used.

Third Embodiment In the first and second embodiments, the case where only one capacitor C1 is provided has been described, but the present invention can also be applied to a circuit having a plurality of such capacitors. That is, an ammeter or a current source circuit is added to each of the plurality of capacitors, or an ammeter or a current source circuit is added to each of the charging routes or discharging routes of the plurality of capacitors. The proportional constants of each current source circuit are set to the same value.

[0038]

As described above, according to the first aspect of the invention, the capacitor in the circuit to be subjected to the circuit simulation having a time constant larger than the signal period handled in the circuit to be subjected to the circuit simulation is used. On the other hand, the additional current source for high-speed charging / discharging allows high-speed charging / discharging to shift to a steady state, and the time constant of the above capacitor is configured to be apparently small. This has the effects of reducing the number of analysis points, reducing the sum of the analysis times required for the calculations performed for each analysis point, and suppressing the amount of analysis data obtained as a result of analysis.

According to the second aspect of the invention, the capacitor in the circuit to be subjected to the circuit simulation, which has a time constant larger than the signal period handled by the circuit to be subjected to the circuit simulation, is charged and / or discharged. The current source for high-speed charging / discharging that is added for each route of (1) makes it possible to perform charging / discharging at high speed to shift to a steady state, and the time constant of the above capacitor is configured to be apparently small. The number of analysis points required for each analysis point can be reduced, the total sum of each analysis time required for the calculation performed for each analysis point can be shortened, and the amount of analysis data obtained as a result of analysis can be suppressed.

According to the third aspect of the invention, the high-speed charge added to the capacitor in the circuit to be subjected to the circuit simulation, which has a time constant larger than the signal period handled in the circuit to be subjected to the circuit simulation. Since the discharge current source performs high-speed charging / discharging at high speed and shifts to a steady state, the current amount flowing through the high-speed charging / discharging current source is configured to be zero, so the total analysis time such as calculation can be shortened. At the same time, an increase in the amount of analysis data obtained as a result of the analysis can be suppressed, and there is an effect that more accurate circuit analysis can be realized.

According to the invention of claim 4, the capacitor in the circuit to be subjected to the circuit simulation, which has a time constant larger than the signal period handled in the circuit to be subjected to the circuit simulation, is charged and / or discharged. The high-speed charging / discharging current source is added to each route to perform high-speed charging / discharging, and after shifting to a steady state, the current amount flowing through the high-speed charging / discharging current source is set to zero. The number of analysis points required for characteristic analysis on the time axis can be reduced, the total analysis time required for the calculations performed for each analysis point can be shortened, and the increase in the amount of analysis data obtained as a result of analysis can be suppressed. In addition, there is an effect that a circuit analysis with high accuracy can be realized.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a circuit simulation device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram including a capacitor having a time constant larger than a normal signal period, which is analyzed by the circuit simulation apparatus according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a current source circuit addition program of the circuit simulation device according to the embodiment of the invention of claim 1;

FIG. 4 is a circuit including a capacitor having a time constant larger than that of a normal signal, to which a current source circuit or the like is added by a current source circuit addition program of a circuit simulation device according to an embodiment of the present invention; It is a figure.

FIG. 5 is a conceptual diagram showing a circuit simulation device according to an embodiment of the invention of claim 2;

FIG. 6 shows a capacitor having a time constant larger than a normal signal cycle, to which a current source circuit or the like is added by a route-specific current source circuit addition program of the circuit simulation apparatus according to the second embodiment of the invention. It is a circuit diagram including

FIG. 7 is a conceptual diagram showing a conventional circuit simulation device.

FIG. 8 is a circuit diagram including a capacitor analyzed by a conventional circuit simulation device and having a time constant larger than a normal signal cycle.

[Explanation of symbols]

1 circuit simulation device 3 circuit simulator (circuit analysis means) 4 analysis result output program (analysis result output means) 6 current source circuit addition program (high-speed charging / discharging current source addition means, charging / discharging current amount control means) 7 by route Current source circuit addition program (addition means for each high-speed charging / discharging current source route) C1 capacitors CIR1, CIR2, CIR3 current source circuit (high-speed charging / discharging current source)

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[Procedure amendment]

[Submission date] September 20, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

FIG. 7 is a conceptual diagram showing the configuration of a circuit simulation device using the above circuit simulator. In the figure, reference numeral 1 is a circuit simulation apparatus body including a circuit simulator 3 and an analysis result output program 4 for outputting data analyzed by the circuit simulator 3. Reference numeral 2 denotes a circuit to be analyzed, for example, an AGC circuit, which includes a time constant larger than the cycle of the signal handled by the circuit to be simulated. FIG. 8 shows a part of a circuit diagram which is a target of this circuit analysis.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

On the other hand, if the maximum period of the signals handled by the target circuit 2 is T2, the analysis time to be simulated is at least one period T2 of this signal, and it is necessary to perform the simulation during this period. As a result, the number of analysis points in the circuit simulator 3 depends on the ratio of the maximum period T2 and the minimum period T1. Further, when the target circuit 2 has a time constant T3 larger than the maximum period T2, it is necessary to perform simulation for at least the period T3 based on this time constant.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007] In contrast, to predict such as a voltage value after the transition to the steady state, or circuit simulation, for example, by initializing the predicted value, or a circuit at the element level, such as a transistor by mathematical model There is a method of analyzing a target circuit such as an AGC circuit including a time constant larger than the cycle of a signal to be handled by performing numerical calculation instead of circuit simulation.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

The inventions of claims 1 and 2 were made in order to solve the above problems, and shorten the total number of analysis times such as calculation, and at the same time, obtain an analysis result. An object is to obtain a circuit simulation device that can suppress an increase in the amount of data.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

According to the third and fourth aspects of the present invention, the total number of analysis times such as calculations can be shortened and an increase in the amount of analysis data obtained as a result of analysis can be suppressed, so that circuit analysis can be performed accurately. The purpose is to obtain a circuit simulation device capable of

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

FIG. 2 is a part of circuit data showing the target circuit 2 and shows a low pass filter circuit. In the figure, Q1 and Q2 are transistors, C1 is a capacitor having a relatively large capacitance and a large time constant, R1 is a resistor connected in parallel with the capacitor C1, and the numbers in the square boxes indicate node numbers.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

Next, the operation will be described. In this circuit simulation device, a current source for forcibly charging / discharging the capacitor C1 of the target circuit 2 when a simulation is performed on the target circuit 2 and a circuit analysis is performed.
The circuit is added by the current source circuit addition program 6.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

FIG. 3 shows this current source circuit addition program 6
A flowchart showing, especially when explaining the operation based on this flow chart, the charge and discharge route to the capacitor C1 of the circuit 2 inputted in step ST1
Set . This specified charging / discharging route is the signal line connected to the capacitor C1 at the node 2. In the next step ST2, an ammeter for measuring the original charging / discharging current of the capacitor C1 is installed. In the following step ST3, a current source circuit for adding a current amount proportional to the current value flowing through the ammeter installed in step ST2 to the capacitor C1 through another route is added. That is, a charging / discharging current amount of a constant multiple of the original charging / discharging current value of the capacitor C1 indicated by the installed ammeter is caused to flow into or discharge from the capacitor C1 by another route by the added current source circuit. In step ST4, a proportional constant k that determines how many times the current value that is originally charged and discharged from the capacitor C1 is flown into or discharged from the current source circuit in the capacitor C1 is determined.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

When the circuit data shown in FIG. 4 is input to the circuit simulator 3 and analyzed on the time axis, the current source circuit CI
Charging / discharging is performed from R1 with a current amount k times the original charging / discharging current value of the capacitor C1, and the capacitor C1 reaches a steady state in about 1 / k times the time. As a result, the number of analysis points on the time axis for analysis is almost 1 / k, and the amount of data obtained as a result of analysis is also reduced. A small amount of memory is used as the memory for storing the data that is this analysis result. You will be able to. further,
It can be expected that the transient response time of the circuit of FIG. 2 will be approximately k times that of the circuit of FIG.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

If the proportional constants k1 and k2 are set to the same value, the response time until the steady state is reached in the original circuit shown in FIG. 2 can be predicted. That is, the circuit simulation
Substantially k times (k = k response time by the analysis result of the regulator 3
1 = k2) is the response time until the steady state in the original circuit shown in FIG. 2 is reached.

[Procedure Amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction content]

As described above, according to this embodiment,
In the case where the ammeter and the current source circuit as necessary are added to the charging or discharging routes, respectively, the circuit configuration to be analyzed is complicated and there are multiple charging / discharging routes for the capacitor C1. However, the circuit analysis can be performed with high accuracy, the circuit analysis of the circuit including the capacitor C1 having a large time constant can be performed in a short time, and the data amount obtained as a result of the circuit analysis can be reduced. A small capacity memory can be used as a memory for storing the data obtained as a result of this analysis.

[Procedure Amendment 12]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

FIG. 2 is a part of a circuit diagram including a capacitor having a time constant larger than that of a normal signal analyzed by the circuit simulation apparatus according to the first embodiment of the present invention.

[Procedure Amendment 13]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

[Procedure Amendment 14]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

[Procedure Amendment 15]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

[Figure 5]

[Procedure Amendment 16]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction content]

[Figure 7]

Claims (4)

[Claims] 1. A high-speed charging / discharging current for shifting to a steady state by rapidly charging / discharging a capacitor in the circuit having a time constant larger than the signal period handled by the circuit to be subjected to the circuit simulation. A current source for high-speed charging / discharging, which adds a power source to the circuit to be subjected to the circuit simulation, and a circuit analysis means for performing characteristic analysis on the time axis of the circuit to which the high-speed charging / discharging current source is added. A circuit simulation device comprising: an analysis result output means for outputting an analysis result performed by the circuit analysis means. 2. A plurality of high-speed charging / discharging for shifting to a steady state by rapidly charging / discharging a capacitor in the circuit having a time constant larger than a signal period handled by a circuit to be subjected to circuit simulation. Circuit for performing high-speed charging / discharging current source route addition means for adding charging current source for each charging and / or discharging route, and characteristic analysis on the time axis of the circuit to which the high-speed charging / discharging current source is added A circuit simulation device comprising: an analysis means; and an analysis result output means for outputting an analysis result performed by the circuit analysis means. 3. A high-speed charging / discharging current for shifting to a steady state by rapidly charging / discharging a capacitor in the circuit having a time constant larger than a signal period handled by the circuit to be subjected to the circuit simulation. A high-speed charging / discharging current source adding means for adding a power source to a circuit including the capacitor, and the capacitor is charged and discharged at high speed by the high-speed charging / discharging current source, and after shifting to a steady state,
A charging / discharging current amount control means for reducing the amount of current flowing through the high-speed charging / discharging current source to zero, and a circuit analysis means for performing characteristic analysis on the time axis of the circuit to which the high-speed charging / discharging current source is added. A circuit simulation device comprising: an analysis result output means for outputting an analysis result performed by the circuit analysis means. 4. A plurality of high-speed charging / discharging current sources for charging / discharging a capacitor in the circuit having a time constant larger than a signal period handled by a circuit to be subjected to circuit simulation at a high speed and shifting to a steady state. Is added to each charge and / or discharge route for each high-speed charging / discharging current source route, and the high-speed charging / discharging current source causes the capacitor to be rapidly charged / discharged to shift to a steady state. After that, the charging / discharging current amount control means for reducing the amount of current flowing through the high-speed charging / discharging current source to zero, and a circuit for analyzing characteristics on a time axis of the circuit to which the high-speed charging / discharging current source is added A circuit simulation device comprising: an analysis means; and an analysis result output means for outputting an analysis result performed by the circuit analysis means.