JP5262952B2 - Simulation system and simulation method - Google Patents

Description

  The present invention relates to a simulation system and a simulation method for simulating a high frequency power amplifier used in a microwave band and a millimeter wave band.

  In recent years, with the progress of miniaturization of CMOS, higher speed and higher frequency of CMOS are accelerated, while the operating voltage of CMOS continues to decrease. For example, in the case of a CMOS having a gate length of 90 nm or less, the operating voltage is 1 V or less.

  The cause of the decrease in the operating voltage of CMOS is that with the miniaturization of CMOS, the voltage applied to the gate insulating film, between the gate terminal and the drain terminal, and between the drain terminal and the source terminal in the transistor has increased. Is mentioned.

  When a high voltage is applied to the CMOS, the time until the transistor fails or deteriorates due to HCI (Hot Carrier Injection), TDDB (Time Dependent Dielectric Breakdown), or NBTI (Negative Bias Temperature Instability) ( Hereinafter, this is referred to as “lifetime”. Therefore, the lifetime of the CMOS has a very strong correlation with the voltage applied to the transistor.

  When the operating voltage of the CMOS decreases, the performance of the analog circuit, particularly the output power of the power amplifier, deteriorates. This is because the output power of the power amplifier is generally proportional to the square of the operating voltage of the CMOS.

  Therefore, when designing a power amplifier using a fine CMOS, in order to increase the output power of the power amplifier, it is desired to increase the operating voltage of the CMOS even by 0.1 V within the range that satisfies the transistor life. There is a strong demand. For example, increasing the CMOS operating voltage from 0.5 V to 0.6 V improves the output power of the power amplifier by 40% or more.

  Technologies for calculating the lifetime of a CMOS are disclosed in, for example, Patent Document 1 and Patent Document 2.

Japanese Patent Laid-Open No. 9-283577 JP 2005-259777 A

  However, in the prior art disclosed in Patent Document 1 and Patent Document 2, it is possible to calculate the lifetime of a digital circuit, an analog circuit, or the like, but a high-frequency circuit used in a microwave band or a millimeter wave band, In particular, there is a problem that the life and output power of the high-frequency power amplifier cannot be calculated. This is because in the prior art, the lifetime is not calculated in consideration of the load impedance of the transistor matching circuit.

  In the case of a high frequency power amplifier, the instantaneous voltage applied to the CMOS exceeds the operating voltage. This instantaneous voltage depends not only on the operating voltage but also on the load impedance of the matching circuit. Similarly, the output power of the high-frequency power amplifier depends on the load impedance of the matching circuit. Therefore, in the prior art that does not take into account any load impedance of the transistor matching circuit, the life and output power of the high-frequency power amplifier cannot be calculated.

  Therefore, an object of the present invention is to provide a simulation system and a simulation method capable of designing a high-frequency power amplifier that satisfies the life and has a desired output power, which is a problem of the prior art.

In order to achieve the above object, a first simulation system of the present invention includes:
A simulation system for simulating a high-frequency power amplifier,
A transistor model input section for inputting a transistor model;
A transistor model parameter input unit for inputting transistor model parameters;
An operating voltage input section for inputting the operating voltage of the transistor;
A reliability information input unit for inputting transistor reliability information;
An output power simulation unit that refers to the transistor model, the transistor model parameter, and the operating voltage, and calculates the output power of the transistor by changing the load impedance of the matching circuit of the transistor;
A lifetime simulation unit that refers to the transistor model, the transistor model parameter, the operating voltage, and the reliability information, changes a load impedance of a matching circuit of the transistor, and calculates a lifetime of the transistor;
A display unit for displaying the calculated output power and lifetime on a Smith chart diagram,
A load impedance extracting unit that extracts a desired load impedance with reference to the output power and the life displayed on the contour line on the Smith chart.

In order to achieve the above object, the second simulation system of the present invention provides:
A simulation system for simulating a high-frequency power amplifier,
A transistor model input section for inputting a transistor model;
A transistor model parameter input unit for inputting transistor model parameters;
An amplifier target performance input unit for inputting a desired output power value of the high-frequency power amplifier;
A matching circuit information input unit for inputting transistor matching circuit information;
An operating voltage input section for inputting the operating voltage of the transistor;
A reliability information input unit for inputting transistor reliability information;
Referring to the transistor model, the transistor model parameter, the matching circuit information, and the operating voltage, an output power simulation unit for calculating the output power of the transistor;
A lifetime simulation unit that calculates the lifetime of a transistor by referring to the transistor model, the transistor model parameter, the matching circuit information, the operating voltage, and the reliability information;
A display unit for displaying the calculated output power and lifetime on a Smith chart diagram,
A determination unit that determines whether or not a desired output power value exists in the load impedance region that satisfies the life with reference to the output power and the life displayed on the contour line on the Smith chart,
When the determination unit determines that the desired output power value does not exist in the load impedance region that satisfies the lifetime, accepting re-input of the desired output power value, the matching circuit information, and the operating voltage. Features.

In order to achieve the above object, the first simulation method of the present invention comprises:
A simulation method for simulating a high-frequency power amplifier,
Receiving a transistor model input;
Accepting input of transistor model parameters;
Receiving an input of an operating voltage of the transistor;
Accepting input of transistor reliability information;
Referring to the transistor model, the transistor model parameter, and the operating voltage, and calculating a transistor output power by changing a load impedance of a matching circuit of the transistor;
Referring to the transistor model, the transistor model parameter, the operating voltage, and the reliability information, changing a load impedance of a matching circuit of the transistor, and calculating a lifetime of the transistor;
Displaying the calculated output power and life on a Smith chart with contour lines;
A step of extracting a desired load impedance with reference to the output power and the life displayed on the contour line on the Smith chart.

In order to achieve the above object, the second simulation method of the present invention comprises:
A simulation method for simulating a high-frequency power amplifier,
Receiving a transistor model input;
Accepting input of transistor model parameters;
Receiving an input of a desired output power value of the high-frequency power amplifier;
Receiving input of transistor matching circuit information;
Receiving an input of an operating voltage of the transistor;
Accepting input of transistor reliability information;
Referring to the transistor model, the transistor model parameter, the matching circuit information, and the operating voltage, and calculating an output power of the transistor;
Referring to the transistor model, the transistor model parameter, the matching circuit information, the operating voltage, and the reliability information, and calculating a lifetime of the transistor;
Displaying the calculated output power and life on a Smith chart with contour lines;
Determining whether or not a desired output power value exists in the load impedance region satisfying the life with reference to the output power and the life displayed on the contour line on the Smith chart diagram; and
Receiving the desired output power value, the matching circuit information, and the re-input of the operating voltage when it is determined that the desired output power value does not exist in the load impedance region that satisfies the lifetime. Features.

  According to the first simulation system of the present invention, the output power and life of the transistor are calculated, and displayed on the contour chart on the Smith chart, and then the load impedance for obtaining the life and output power of the transistor is extracted. It is possible to design a high-frequency power amplifier satisfying the above and having a desired output power.

  According to the second simulation system of the present invention, the output power and lifetime of the transistor are calculated, displayed on a contour line on the Smith chart, and it is determined whether or not there is output power capable of obtaining the lifetime of the transistor. Until the input of the desired output power value, matching circuit information, and operating voltage is repeated, it becomes possible to design a high-frequency power amplifier that satisfies the lifetime and has the desired output power.

It is a block diagram which shows the structure of the principal part of the simulation system of the 1st Embodiment of this invention. It is a flowchart which shows the simulation method by the simulation system shown in FIG. It is a figure which shows the load line and load circle of a high frequency power amplifier. It is a figure which shows the board | substrate current on the load line of a high frequency power amplifier. It is a figure displayed with the simulation system shown in FIG. It is a block diagram which shows the structure of the principal part of the simulation system of the 2nd Embodiment of this invention. It is a flowchart which shows the simulation method by the simulation system shown in FIG.

  Next, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of the main part of the simulation system according to the first embodiment of the present invention.

  The simulation system of the present embodiment is a circuit simulator realized by a computer that operates according to a program, and is used for designing a high-frequency power amplifier.

  As shown in FIG. 1, the main part of the simulation system of this embodiment includes a condition input unit 11, a simulation unit 12, a display unit 13, and a load impedance extraction unit 14.

  The condition input unit 11 includes a transistor model input unit 111, a transistor model parameter input unit 112, a reliability information input unit 113, and an operating voltage input unit 14.

  The simulation unit 12 includes an output power simulation unit 121 and a life simulation unit 122.

  Hereinafter, a simulation method by the simulation system of the present embodiment will be described with reference to FIG.

  As shown in FIG. 2, first, in step A1, a transistor model is input to the transistor model input unit 111. Subsequently, in step A2, a transistor model parameter is input to the transistor model parameter input unit 112.

  The transistor model is a general transistor model such as BSIM (Berkeley Short-channel IGFET Model, IGFET = Insulated-Gate Field-Effect Transistor) or HiSIM (Hiroshima-university STARC IGFET Model, STARC = Semiconductor Technology Academic Research Center). .

  The transistor model parameter is a parameter of a transistor model such as BSIM or HiSIM.

  On the other hand, in step A 3, transistor reliability information is input to the reliability information input unit 113.

  The reliability information is information depending on the transistor structure, and is, for example, a relational expression between the voltage applied to the transistor and the lifetime.

  The reliability information may be a relational expression between the substrate current and the lifetime of the transistor. By using the relational expression between the transistor substrate current and the lifetime, the lifetime of the CMOS due to the HCI can be easily and accurately calculated. This is because the lifetime of the CMOS has a strong correlation with the substrate current.

  The relational expression between the substrate current and the lifetime is, for example, lifetime = α × (substrate current) β. However, α and β are parameters depending on the transistor structure.

  The reliability information may be a relational expression between the junction temperature and the lifetime of the transistor. By using the relational expression between the junction temperature and the lifetime of the transistor, it is possible to calculate the lifetime of not only a CMOS but also a semiconductor such as GaAs or GaN.

  The relational expression between the junction temperature and the lifetime is, for example, lifetime = a × exp (b / junction temperature). However, a and b are parameters depending on the transistor structure.

  Next, in step A4, the operating voltage of the transistor is input to the operating voltage input unit 114.

  The transistor model input unit 111, the transistor model parameter input unit 112, the reliability information input unit 113, and the operating voltage input unit 114 supply the conditions input in steps A1 to A4 to the simulation unit 12.

  Next, in step A5, the output power simulation unit 121 refers to the transistor model, the transistor model parameter, and the operating voltage, calculates the output power of the transistor by changing the load impedance of the matching circuit of the transistor, and calculates the result. This is supplied to the display unit 13.

  On the other hand, in step A6, the lifetime simulation unit 122 refers to the transistor model, transistor model parameter, operating voltage, and reliability information, calculates the lifetime of the transistor by changing the load impedance of the matching circuit of the transistor, and the result Is supplied to the display unit 13.

  The matching circuit is a circuit configured using one or more resistors, capacitors, inductors, and transmission lines.

  Next, in step A7, as shown in FIG. 5, the display unit 13 displays a contour map of the output power and lifetime of the transistor on the Smith chart, and supplies the result to the load impedance extraction unit 14.

  Thereafter, in step A8, the load impedance extraction unit 14 obtains the desired load impedance that maximizes the output power within the range satisfying the lifetime based on the contour map of the output power and lifetime of the transistor displayed on the display unit 13. To extract.

  The simulation system of the present embodiment is an example of the present invention, and the configuration and operation thereof can be changed in a timely manner. For example, in this embodiment, the output power and lifetime of a transistor are displayed on a Smith chart, but efficiency, distortion, gain, transistor substrate current, transistor performance, which are general indices of a high-frequency power amplifier, are displayed. It is also possible to display the junction temperature.

  As described above, in the present embodiment, the load impedance from which the lifetime of the transistor and the output power can be obtained is extracted. Therefore, it is possible to design a high-frequency power amplifier that satisfies the lifetime and has a desired output power.

(Second Embodiment)
FIG. 6 is a block diagram showing the configuration of the main part of the simulation system according to the second embodiment of the present invention.

  The simulation system of the present embodiment is a circuit simulator realized by a computer that operates according to a program, and is used for designing a high-frequency power amplifier.

  As shown in FIG. 6, the main part of the simulation system of the present embodiment includes a condition input unit 21, a simulation unit 22, a display unit 23, and a determination unit 24.

  The condition input unit 21 includes a transistor model input unit 211, a transistor model parameter input unit 212, an amplifier target performance input unit 213, a matching circuit information input unit 214, a reliability information input unit 215, and an operating voltage input unit 216. Has been.

  The simulation unit 22 includes an output power simulation unit 221 and a life simulation unit 222.

  Hereinafter, a simulation method by the simulation system of the present embodiment will be described with reference to FIG.

  As shown in FIG. 7, first, in step B1, the transistor model is input to the transistor model input unit 211. Subsequently, in step B2, the transistor model parameter is input to the transistor model parameter input unit 212. In B3, the desired output power value Ps of the high frequency power amplifier is input to the amplifier target performance input unit 213, and subsequently, the matching circuit information of the transistor is input to the matching circuit information input unit 214 in Step B4.

  The matching circuit is a circuit configured using one or more resistors, capacitors, inductors, and transmission lines.

  The transistor model and the transistor model parameters are the same as those described in the first embodiment.

  On the other hand, in step B <b> 5, transistor reliability information is input to the reliability information input unit 215.

  The reliability information is the same as that described in the first embodiment.

  Next, in step B <b> 6, the operating voltage of the transistor is input to the operating voltage input unit 216.

  The transistor model input unit 211, the transistor model parameter input unit 212, the amplifier target performance input unit 213, the matching circuit information input unit 214, the reliability information input unit 215, and the operating voltage input unit 216 are input in steps B1 to B6. The conditions thus obtained are supplied to the simulation unit 22.

  Next, in step B7, the output power simulation unit 221 refers to the transistor model, transistor model parameters, matching circuit information, and operating voltage, calculates the output power of the transistor, and supplies the result to the display unit 23.

  On the other hand, in step B8, the lifetime simulation unit 222 refers to the transistor model, transistor model parameters, matching circuit information, operating voltage, and reliability information, calculates the lifetime of the transistor, and supplies the result to the display unit 23. .

  Next, the display part 23 displays the output power and lifetime of a transistor on a Smith chart figure in step B9, and supplies the result to the determination part 24. FIG.

  On the Smith chart, it is desirable to display the output power and life as a contour map as shown in FIG.

  Thereafter, in step B10, the determination unit 24 determines whether or not the desired output power value Ps exists in the load impedance region that satisfies the life based on the output power and life of the transistor displayed on the display unit 23.

  The determination unit 24 ends the simulation when the desired output power Ps exists in the load impedance region where the lifetime can be obtained.

  On the other hand, when the desired output power Ps does not exist in the load impedance region where the lifetime can be obtained, the determination unit 24 returns to the process of step B3 and thereafter re-inputs the value of Ps, the matching circuit information, and the operating voltage. Accept.

  The simulation system of the present embodiment is an example of the present invention, and the configuration and operation thereof can be changed in a timely manner. For example, in this embodiment, the output power is the target value, but it is also possible to set the efficiency, distortion, and gain, which are general indices of the high-frequency power amplifier, as target values.

  As described above, in the present embodiment, the input of the value of Ps, the matching circuit information, and the operating voltage is repeated until there is output power at which the lifetime of the transistor can be obtained. It becomes possible to design a high-frequency power amplifier having

DESCRIPTION OF SYMBOLS 11 Condition input part 111 Transistor model input part 112 Transistor model parameter input part 113 Reliability information input part 114 Operating voltage input part 12 Simulation part 121 Output power simulation part 122 Life simulation part 13 Display part 14 Load impedance extraction part 21 Condition input part 211 transistor model input unit 212 transistor model parameter input unit 213 amplifier target performance input unit 214 matching circuit information input unit 215 reliability information input unit 216 operating voltage input unit 22 simulation unit 221 output power simulation unit 222 life simulation unit 23 display unit 24 Judgment part

Claims (12)

A simulation system for simulating a high-frequency power amplifier,
A transistor model input section for inputting a transistor model;
A transistor model parameter input unit for inputting transistor model parameters;
An operating voltage input section for inputting the operating voltage of the transistor;
A reliability information input unit for inputting transistor reliability information;
An output power simulation unit that refers to the transistor model, the transistor model parameter, and the operating voltage, and calculates the output power of the transistor by changing the load impedance of the matching circuit of the transistor;
A lifetime simulation unit that refers to the transistor model, the transistor model parameter, the operating voltage, and the reliability information, changes a load impedance of a matching circuit of the transistor, and calculates a lifetime of the transistor;
A display unit for displaying the calculated output power and lifetime on a Smith chart diagram,
A simulation system comprising: a load impedance extraction unit that extracts a desired load impedance by referring to the output power and the life displayed on the contour line on the Smith chart. A simulation system for simulating a high-frequency power amplifier,
A transistor model input section for inputting a transistor model;
A transistor model parameter input unit for inputting transistor model parameters;
An amplifier target performance input unit for inputting a desired output power value of the high-frequency power amplifier;
A matching circuit information input unit for inputting transistor matching circuit information;
An operating voltage input section for inputting the operating voltage of the transistor;
A reliability information input unit for inputting transistor reliability information;
Referring to the transistor model, the transistor model parameter, the matching circuit information, and the operating voltage, an output power simulation unit for calculating the output power of the transistor;
A lifetime simulation unit that calculates the lifetime of a transistor by referring to the transistor model, the transistor model parameter, the matching circuit information, the operating voltage, and the reliability information;
A display unit for displaying the calculated output power and lifetime on a Smith chart diagram,
A determination unit that determines whether or not a desired output power value exists in the load impedance region that satisfies the life with reference to the output power and the life displayed on the contour line on the Smith chart,
When the determination unit determines that the desired output power value does not exist in the load impedance region that satisfies the lifetime, accepting re-input of the desired output power value, the matching circuit information, and the operating voltage. A featured simulation system. The simulation system according to claim 1 or 2,
The simulation system characterized in that the reliability information is a relational expression between a substrate current and a lifetime of a transistor. The simulation system according to claim 3,
The simulation system, wherein the display unit displays a substrate current of a transistor in a contour line on the Smith chart. The simulation system according to claim 1 or 2,
The simulation system characterized in that the reliability information is a relational expression between a junction temperature and a lifetime of a transistor. The simulation system according to claim 5,
The display unit displays a junction temperature of a transistor in a contour line on the Smith chart diagram. A simulation method for simulating a high-frequency power amplifier,
A transistor model input unit receiving an input of the transistor model;
A transistor model parameter input unit receiving an input of transistor model parameters;
An operation voltage input unit receiving an input of an operation voltage of the transistor;
A step in which the reliability information input unit accepts input of transistor reliability information;
An output power simulation unit refers to the transistor model, the transistor model parameter, and the operating voltage, and calculates a transistor output power by changing a load impedance of a matching circuit of the transistor;
A life simulation unit refers to the transistor model, the transistor model parameter, the operating voltage, and the reliability information, and changes a load impedance of a matching circuit of the transistor to calculate a life of the transistor;
A display unit displaying the calculated output power and life on a Smith chart with contour lines;
A load impedance extracting unit includes a step of extracting a desired load impedance with reference to output power and life displayed on a contour line on the Smith chart diagram. A simulation method for simulating a high-frequency power amplifier,
A transistor model input unit receiving an input of the transistor model;
A transistor model parameter input unit receiving an input of transistor model parameters;
An amplifier target performance input unit receiving an input of a desired output power value of the high-frequency power amplifier;
A matching circuit information input unit receiving input of matching circuit information of a transistor;
An operation voltage input unit receiving an input of an operation voltage of the transistor;
A step in which the reliability information input unit accepts input of transistor reliability information;
An output power simulation unit refers to the transistor model, the transistor model parameter, the matching circuit information, and the operating voltage, and calculates an output power of the transistor;
A life simulation unit refers to the transistor model, the transistor model parameter, the matching circuit information, the operating voltage, and the reliability information, and calculates the life of the transistor;
A display unit displaying the calculated output power and life on a Smith chart with contour lines;
A step of determining whether or not a desired output power value exists in a load impedance region satisfying the life with reference to the output power and the life displayed on the contour line on the Smith chart,
When it is determined that the desired output power value does not exist in the load impedance region that satisfies the lifetime, the amplifier target performance input unit, the matching circuit information input unit, and the operating voltage input unit are configured to output the desired output power value. Receiving the re-input of the matching circuit information and the operating voltage. The simulation method according to claim 7 or 8, wherein
The reliability information is a relational expression between a substrate current and a lifetime of a transistor. The simulation method according to claim 9, wherein
The simulation method characterized in that the display unit includes a step of displaying the substrate current of the transistor in a contour line on the Smith chart. The simulation method according to claim 7 or 8, wherein
The simulation method, wherein the reliability information is a relational expression between a junction temperature and a lifetime of a transistor. The simulation method according to claim 11, comprising:
The simulation method characterized in that the display unit has a step of displaying a junction temperature of a transistor in a contour line on the Smith chart.

Images