Setting method and program

Abstract

To provide a method for setting an N-th order function in a control circuit for applying a control voltage generated by using the N-th order function to a voltage controlled oscillator.SOLUTION: The setting method includes a step of setting, for at least one order of the Nth-order function, a gain and a center temperature of each order of the Nth-order function by using an offset voltage of the inverting path with respect to the non-inverting path of the control circuit. The setting method may include acquiring, at a plurality of temperatures, an offset voltage of the inverting path with respect to the non-inverting path of the control circuit for at least one order of the Nth-order function. Further, a program for causing a computer to execute the setting method is provided.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a setting method and a program. [Background technology]

[0002] Patent Documents 1 to 3 describe temperature compensated crystal oscillation circuits and the like. [Prior art document] [Patent Documents] Patent Document 1: International Publication No. 2004 / 025824 Patent Document 2: Japanese Patent Application Laid-Open No. 2002-76774 Patent Document 3: JP 2016-178606 A Summary of the Invention

[0003] A first aspect of the present invention provides a method for setting an Nth-order function in a control circuit that applies a control voltage generated using the Nth-order function to a voltage-controlled oscillator, the method comprising a step of setting, for at least one order of the Nth-order function, a gain and a central temperature of each order of the Nth-order function using an offset voltage of an inverting path of the control circuit for a non-inverting path. The setting method may comprise a step of acquiring, for at least one order of the Nth-order function, an offset voltage of an inverting path of the control circuit for a non-inverting path at a plurality of temperatures.

[0004] In the above setting method, the step of setting the gain and the central temperature may include a step of determining, using an offset voltage, a first set of candidate values ​​for the gain and central temperature of each order of the Nth-order function when the control voltage is generated via an inverting path of the control circuit; a step of determining a second set of candidate values ​​for the gain and central temperature of each order of the Nth-order function when the control voltage is generated via a non-inverting path of the control circuit; and a step of setting the gain and central temperature of each order of the Nth-order function using the first set of candidate values ​​and the second set of candidate values.

[0005] In the above setting method, the step of determining the first candidate value may include a step of generating a first function by multiplying a gain at each order of the Nth-order function by a voltage corresponding to temperature, a step of generating a second function by incorporating an offset voltage into the target characteristic of the control circuit, and a step of determining a set of first candidate values ​​of the gain at each order of the Nth-order function and the central temperature so that the difference between the first function and the second function is less than a predetermined threshold.

[0006] In any of the above setting methods, the step of determining the second candidate value set may include a step of generating a first function by multiplying a gain at each order of the Nth-order function by a voltage corresponding to temperature, and a step of determining a second candidate value set of the gain at each order of the Nth-order function and the central temperature so that the difference between the first function and the target characteristic of the control circuit is less than a predetermined threshold.

[0007] In any of the above setting methods, the step of setting the gain and the central temperature may include the steps of generating a first function by multiplying the gain at each order of the Nth-order function by a voltage corresponding to the temperature, determining a third set of candidate values ​​for the gain at each order of the Nth-order function and the central temperature so that the difference between the target characteristic of the control circuit and the first function is less than a predetermined threshold, generating a third function by incorporating an offset voltage into the first function, and using the third candidate value set to set the gain at each order of the Nth-order function and the central temperature so that the difference between the third function and the target characteristic of the control circuit is less than a predetermined threshold.

[0008] In any of the above setting methods, the step of acquiring the inverted offset voltage may include a step of acquiring the offset voltage relative to the non-inverted path for each of a plurality of inverted paths of the control circuit at a plurality of temperatures, and the step of setting the gain and the center temperature may include a step of determining a fourth candidate value set of the gain of each order of the Nth-order function and the center temperature for each of a plurality of combinations of the inverted path and the non-inverted path used to generate the control voltage, and a step of setting one of the plurality of fourth candidate value sets as the gain of each order of the Nth-order function and the center temperature.

[0009] In any of the above setting methods, the step of acquiring the offset voltage may include a step of acquiring the offset voltage for each of a plurality of inverting paths of the control circuit relative to a non-inverting path at a plurality of temperatures, and the step of setting the gain and the central temperature may include a step of generating a first function by multiplying the gain for each order of the Nth-order function by a voltage corresponding to the temperature, a step of determining a third candidate value set of the gain for each order of the Nth-order function and the central temperature so that the difference between the target characteristic of the control circuit and the first function is less than a predetermined threshold, a step of generating a third function by incorporating the offset voltages added together according to the signs of the gains for each order of the third candidate value set into the first function, and a step of setting the gain for each order of the Nth-order function and the central temperature using the third candidate value set so that the difference between the third function and the target characteristic of the control circuit is less than a predetermined threshold.

[0010] Any of the above setting methods may include a step of acquiring a first variation amount of each order term at a plurality of temperatures when the gain of at least one order in the Nth-order function is varied, and the step of setting the gain and the central temperature may include a step of setting the gain and the central temperature of each order of the Nth-order function based on the first variation amount and the offset voltage.

[0011] In any of the above setting methods, the step of acquiring the offset voltage may include a step of acquiring, at a plurality of temperatures, the offset voltage between the output of an inverting path that inverts the output signal of a temperature compensation circuit of at least one order of an Nth-order function in the control circuit and the output of a non-inverting path that leaves the output signal non-inverted.

[0012] In a second aspect of the present invention, there is provided a program for causing a computer to execute the setting method of the first aspect.

[0013] The above summary of the invention does not list all of the necessary features of the present invention, and subcombinations of these features may also constitute inventions. [Brief explanation of the drawings]

[0014] [Figure 1] 1 shows an example of the configuration of a temperature compensated oscillator 10 according to this embodiment. [Figure 2] 1 shows an example of the configuration of a setting device 50. [Figure 3] The relationship between the output of the inverting path 126 and the output of the non-inverting path 125 is shown. [Figure 4] 10 shows the operation of setting a setting value by the setting device 50. [Figure 5] The relationship between temperature and control voltage Vccal is shown. [Figure 6] 1 shows the relationship between the first fluctuation amount fn(T−T0) and temperature. [Figure 7] The relationship between the offset voltage Voff and temperature is shown. [Figure 8] An example of shifting the third-order first fluctuation amount f3(T-T0) in the temperature direction is shown. [Figure 9] An example of shifting the fourth-order first fluctuation amount f4(T-T0) in the temperature direction is shown. [Figure 10] An example of calculating the difference between the first function and the second function when the inversion path 126 is used will be shown. [Figure 11] An example of calculating the difference between the first function and the target characteristic when the non-inverting path 125 is used will be shown. [Figure 12] An example of calculating the optimal gain and central temperature using candidate values ​​for the gain of each order of the Nth-order function and candidate values ​​for the central temperature is shown below. [Figure 13] 1 shows a first modified example of the temperature compensated oscillator 10 according to this embodiment. [Figure 14] 1 shows a second modified example of the temperature compensated oscillator 10 according to this embodiment. [Figure 15] 22 illustrates an example computer 2200 in which aspects of the present invention may be embodied, in whole or in part. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0016] 1 shows an example of the configuration of a temperature compensated oscillator 10 according to this embodiment. The temperature compensated oscillator 10 suppresses frequency fluctuations of a voltage controlled oscillator 20 due to temperature changes within a predetermined compensated temperature range. One example of the temperature compensated oscillator 10 is a TCXO (temperature compensated crystal oscillator). The temperature compensated oscillator 10 includes the voltage controlled oscillator 20, a temperature sensor 30, a control circuit 40, and a setting device 50.

[0017] The voltage-controlled oscillator 20 is connected to the control circuit 40. The voltage-controlled oscillator 20 uses an element that oscillates due to the piezoelectric effect, which generates deformation when an electric field is applied. The voltage-controlled oscillator 20 may oscillate at a frequency corresponding to the control voltage VCOUT applied by the control circuit 40. One example of the oscillator used in the voltage-controlled oscillator 20 is a quartz crystal oscillator in which an AT-cut or other quartz crystal is disposed between two electrodes. However, the oscillator used in the voltage-controlled oscillator 20 is not limited to this, and may also be a piezoelectric element (one example is a SAW (Surface Acoustic Wave) oscillator) or a MEMS (Micro Electro Mechanical Systems) oscillator.

[0018] When the oscillator used in the voltage-controlled oscillator 20 is an AT-cut quartz crystal oscillator, the frequency-temperature characteristics have first- and third-order components as the main components, and therefore, when the frequency-temperature characteristics are approximated to the fourth order, they can be expressed by the following equation 1.

[0019]

number

[0020] Here, in Equation 1, Δf / f(T) represents the frequency-temperature characteristic of the voltage-controlled oscillator 20, αn represents the gain at the nth order, T represents the temperature of the voltage-controlled oscillator 20, and T0 represents the center temperature (i.e., the temperature of the center of rotation) of the voltage-controlled oscillator 20. T0 may be the temperature at the inflection point of the third-order component of the frequency-temperature characteristic, and as an example, in an AT-cut quartz voltage-controlled oscillator 20, T0 fluctuates by approximately 28°±5° depending on the product quality, etc.

[0021] If the voltage-frequency characteristic of the voltage-controlled oscillator 20 is considered to be a linear function that is independent of temperature, the frequency-temperature characteristic can be compensated for by setting the input voltage VCOUT(T) to the voltage-controlled oscillator 20 to satisfy the formula 2 (note that the proportionality coefficients of each order are omitted).

[0022]

number

[0023] Here, in Equation 2, VCOUT(T) represents the control voltage output from the control circuit 40 at temperature T, βn represents the gain at order n, T represents the temperature of the voltage-controlled oscillator 20, and T0 represents the center temperature of the Nth-order function, which may be the temperature of the inflection point of the third-order component of the Nth-order function. At this time, since T0 in Equation 1 varies depending on the quality of the product, etc., in order to perform temperature compensation with high precision, T0 in Equation 2 (i.e., the center temperature set in the control circuit 40) must also be varied accordingly.

[0024] The temperature sensor 30 is connected to the control circuit 40. The temperature sensor 30 detects the temperature of the voltage-controlled oscillator 20 and outputs a sense voltage V tmp to the control circuit 40. The temperature sensor 30 is arranged in contact with or in the vicinity of the voltage-controlled oscillator 20, and may detect the temperature of the voltage-controlled oscillator 20 itself or the temperature of the ambient environment of the voltage-controlled oscillator 20. The temperature sensor 30 outputs a sense voltage V that changes linearly with temperature changes. tmp may be output.

[0025] The control circuit 40 controls the sense voltage V tmp The control circuit 40 applies a control voltage VCOUT generated using an N-th order function (where N is an integer equal to or greater than 1) in response to an input of the voltage-controlled oscillator 20. The control circuit 40 may compensate for the temperature characteristics of the frequency of the voltage-controlled oscillator 20 by generating the control voltage VCOUT in response to a temperature change of the voltage-controlled oscillator 20 using the N-th order function. The control circuit 40 includes an input offset supplying unit 100, an adding unit 110, a fourth-order temperature compensation circuit 120, a first amplifier 122, a sign switching unit 124, a third-order temperature compensation circuit 130, a second amplifier 135, a first-order temperature compensation circuit 140, a third amplifier 145, a zeroth-order temperature compensation circuit 150, and a control voltage supplying circuit 160.

[0026] Here, the control circuit 40 of this embodiment generates the control voltage using an approximate quartic function (N=4) obtained by fourth-order approximation of the frequency-temperature characteristic of the voltage-controlled oscillator 20, but is not limited to this, and the control circuit 40 may use an N-th order function (N≧5) that approximates the frequency-temperature characteristic of the voltage-controlled oscillator 20 with an order of 5 or more. In this case, the control circuit 40 may further include a temperature compensation circuit and amplifier or a code switching unit corresponding to an order of 5 or more.

[0027] The input offset supplying unit 100 is connected to the adding unit 110. The input offset supplying unit 100 may output a preset input offset voltage to the adding unit 110. The input offset supplying unit 100 may output an input offset voltage that corresponds to the center temperature of the Nth-order function.

[0028] The adder 110 is connected to the temperature sensor 30. The adder 110 calculates the sense voltage V tmp The offset voltage output by the input offset supply unit 100 is added to the sum signal V tmp2 You can output V tmp By adjusting the offset added to V tmp2 (i.e., the input voltage of the Nth-order function circuit) is shifted in the temperature direction. This allows the adder 110 to shift the center temperature T0 of the Nth-order function generated by the control circuit 40.

[0029] The fourth-order temperature compensation circuit 120 is connected to the adder 110. The fourth-order temperature compensation circuit 120 receives the sum signal V output from the adder 110. tmp2 In response to the above, a fourth-order component signal of the Nth-order function (that is, an output voltage or current corresponding to the value of the fourth-order term of the Nth-order function) may be output.

[0030] The first amplifier 122 is connected to the fourth-order temperature compensation circuit 120. The first amplifier 122 may amplify the fourth-order component signal output by the fourth-order temperature compensation circuit 120 by a preset gain β4 and output the amplified signal.

[0031] The code switching unit 124 is connected to the first amplifier 122 and the control voltage supply circuit 160. The code switching unit 124 may switch the path through which the signal output by the first amplifier 122 passes between a non-inverting path 125 and an inverting path 126. The code switching unit 124 has a first switch 127, an inverting circuit 128, and a second switch 129.

[0032] The first switch 127 is disposed in a non-inverting path 125 between the first amplifier 122 and the control voltage supply circuit 160. The inverting circuit 128 and the second switch 129 are connected in parallel with the first switch 127 and are disposed in an inverting path 126 between the first amplifier 122 and the control voltage supply circuit 160. The inverting circuit 128 includes, for example, an operational amplifier that inverts (multiplies by -1) an input signal and outputs the inverted signal. The inverting circuit 128 may invert the signal output by the first amplifier 122 and output the inverted signal.

[0033] The sign switching unit 124 may select the non-inverting path 125 by turning on the first switch 127 and turning off the second switch 129, and output the signal output by the first amplifier 122 non-inverted (i.e., multiplied by +1) to the control voltage supply circuit 160 via the non-inverting path 125. The sign switching unit 124 may select the inverting path 126 by turning off the first switch 127 and turning on the second switch 129, and invert the signal output by the first amplifier 122 in the inverting circuit 128 via the inverting path 126 (i.e., multiplied by −1), and output the signal to the control voltage supply circuit 160. The sign switching unit 124 may output the output signal of the first amplifier 122 via the inverting path 126 when the gain βn of the corresponding order (in this embodiment, the fourth-order gain β4) is a negative value. The sign switching section 124 may output the output signal of the first amplifier 122 via the non-inverting path 125 when the gain βn of the corresponding order (the fourth-order gain β4 in this embodiment) is a positive value.

[0034] The third-order temperature compensation circuit 130 is connected to the adder 110. The third-order temperature compensation circuit 130 receives the sum signal V output from the adder 110. tmp2 In response to the above, a third-order component signal of the Nth-order function (that is, an output voltage or current corresponding to the value of the third-order term of the Nth-order function) may be output.

[0035] The second amplifier 135 is connected to the third-order temperature compensation circuit 130. The second amplifier 135 may amplify the third-order component signal output by the third-order temperature compensation circuit 130 by a preset gain β3 and output the amplified signal.

[0036] The primary temperature compensation circuit 140 is connected to the adder 110. The primary temperature compensation circuit 140 receives the sum signal V output from the adder 110. tmp2 In response to the above, a first-order component signal (that is, an output voltage or current corresponding to the value of the first-order term of the N-th order function) may be output.

[0037] The third amplifier 145 is connected to the first-order temperature compensation circuit 140. The third amplifier 145 may amplify the first-order component signal output by the first-order temperature compensation circuit 140 by a preset gain β1 and output the amplified signal.

[0038] The zeroth-order temperature compensation circuit 150 is connected to the control voltage supply circuit 160. The zeroth-order temperature compensation circuit 150 may output a zeroth-order component signal of an Nth-order function (i.e., a voltage corresponding to the value of the zeroth-order term of the Nth-order function). The zeroth-order temperature compensation circuit 150 may output a voltage according to a preset gain β0 (for example, a voltage obtained by multiplying or adding the gain β0 to a reference voltage input to the zeroth-order temperature compensation circuit 150) as the zeroth-order component signal.

[0039] The control voltage supply circuit 160 is connected to the code switching unit 124, the second amplifier 135, the third amplifier 145, and the voltage-controlled oscillator 20. The control voltage supply circuit 160 may output a control voltage VCOUT to the voltage-controlled oscillator 20 according to the outputs of the code switching unit 124, the second amplifier 135, the third amplifier 145, and the zero-order temperature compensation circuit 150. The control voltage supply circuit 160 may generate the control voltage VCOUT by adding together the output voltages of the code switching unit 124, the second amplifier 135, the third amplifier 145, and the zero-order temperature compensation circuit 150.

[0040] The setting device 50 is connected to the control circuit 40. The setting device 50 may be a computer such as a personal computer (PC), a tablet computer, a smartphone, a workstation, a server computer, or a general-purpose computer, or may be a computer system in which multiple computers are connected. Such a computer system is also a computer in the broad sense. The setting device 50 may also be implemented as one or more virtual computer environments executable within a computer.

[0041] The setting device 50 may set various setting values ​​in the control circuit 40. The setting device 50 sets an Nth-order function in the control circuit 40. The setting device 50 may, for example, calculate a gain βn and a central temperature for each order of the Nth-order function and set them in the control circuit 40.

[0042] 2 shows an example configuration of the setting device 50. The setting device 50 includes an acquisition unit 300, a calculation unit 310, and an output unit 320. The acquisition unit 300 is connected to at least one of an input device (e.g., a PC, a mouse, or a keyboard) that receives user input, the control circuit 40, and the voltage-controlled oscillator 20. The acquisition unit 300 may acquire various data necessary to calculate multiple setting values ​​related to the Nth-order function (e.g., gain βn and core temperature) from at least one of the input device that receives user input, the control circuit 40, and the voltage-controlled oscillator 20. The acquisition unit 300 outputs the acquired data to the calculation unit 310.

[0043] The calculation section 310 is connected to the acquisition section 300 and the output section 320. The calculation section 310 may use the data acquired by the acquisition section 300 to calculate a plurality of setting values ​​related to the Nth-order function (for example, the gain βn and the central temperature).

[0044] The output unit 320 is connected to the control circuit 40. The output unit 320 may output the setting value calculated by the calculation unit 310 to the control circuit 40 to set it. The output unit 320 does not have to be connected to the control circuit 40, and may display the calculated setting value so that the user can set it in the control circuit 40.

[0045] 3 shows the relationship between the output of the inverting path 126 and the output of the non-inverting path 125. In FIG. 3, the vertical axis represents voltage, and the horizontal axis represents temperature. In FIG. 3, Va represents the measured value of the output voltage obtained by outputting the output signal of the first amplifier 122 via the non-inverting path 125, Vb represents the value obtained by multiplying the value of Va by −1 (i.e., the predicted value of the voltage obtained by outputting the output signal of the first amplifier 122 via the inverting path 126), and Vc represents the measured value of the output voltage obtained by outputting the output signal of the first amplifier 122 via the inverting path 126.

[0046] As shown in FIG. 3, an offset (hereinafter referred to as offset voltage V) occurs between the output voltage Vc of the inverting path 126 and the output voltage Va of the non-inverting path 125 due to an operational amplifier or the like used in the inverting circuit 128. off Therefore, when the setting device 50 determines the optimum setting value (gain βn and the center temperature of the N-th order function generated by the control circuit 40) for the control circuit 40 using, for example, the output voltage Va of the non-inverting path 125 in the calculation, the gain βn becomes negative, and when the inverting path 126 is used, the offset voltage V off If the temperature compensation accuracy is not taken into account, the offset voltage V off This section explains how to set the setting value taking (T) into consideration.

[0047] 4 shows the setting operation of the setting device 50. In the first example shown below, the setting device 50 sets the compensation temperature range to -30 to 85°C, as an example, and sets the gain βn (βn indicates the gain of the n-th order term in the N-th order function) of a quartic function (N=4) used in the control circuit 40 and the central temperature.

[0048] In step S400, the setting device 50 starts from the temperature T of the voltage-controlled oscillator 20=−30 degrees.

[0049] In step S410, the environmental temperature of the voltage-controlled oscillator 20 is set to a temperature T (initially -30 degrees).

[0050] In step S420, the acquisition unit 300 acquires the control voltage V at which the absolute value of the difference between the output frequency of the voltage-controlled oscillator 20 and the target frequency is less than a predetermined threshold value at the temperature T (for example, the output frequency and the target frequency match). ccal The acquisition unit 300 controls the control circuit 40 and the voltage-controlled oscillator 20 to acquire the actually measured control voltage V ccal The acquisition unit 300 may acquire the control voltage V ccal and the output frequency may be obtained.

[0051] The setting device 50 may set an initial value T0 of the central temperature of the Nth-order function generated by the control circuit 40. The calculation unit 310 may set the initial value T0 of the central temperature by incorporating into the Nth-order function an initial value T0 of the central temperature that is predetermined for each characteristic (such as serial number, material, type, and shape) of the resonator used in the voltage-controlled oscillator 20. The acquisition unit 300 may acquire the initial value T0 of the central temperature from a user.

[0052] In step S430, the acquiring unit 300 may acquire an output voltage for each order for which a plurality of gains βn are respectively set. The acquiring unit 300 may acquire an output voltage for at least one order for which a plurality of gains βn are respectively set, using the inverting path 126 and the non-inverting path 125. For example, the acquiring unit 300 acquires the output voltages of the first amplifier 122, the second amplifier 135, and the third amplifier 145 when the codes for determining the gain βn are set to G1 and G2 (for example, G1 = 0, G2 = 2) for the first amplifier 122, the second amplifier 135, and the third amplifier 145, respectively. In this case, the code switching unit 124 may output the signal output by the first amplifier 122 via the non-inverting path 125. Furthermore, the acquiring unit acquires the output voltage of the first amplifier 122 inverted via the inverting path 126 when the code for determining the gain βn for the first amplifier 122 is set to G3 (for example, G3 = 0).

[0053] The acquiring section 300 may control the control circuit 40 and the voltage-controlled oscillator 20 to acquire actual measured values ​​of the output voltage corresponding to each order when the code determining the gain βn is set to G1, G2, and G3, respectively. Furthermore, the acquiring section 300 may acquire the output voltage corresponding to each order when the code determining the gain βn is set to G1, G2, and G3, respectively, by a simulation using the characteristics of the control circuit 40.

[0054] In step S440, the calculation unit 310 calculates the first fluctuation amount fn(T−T0) and the offset voltage V offFirst, an example in which the calculation unit 310 acquires the first fluctuation amount fn(T-T0) will be described.

[0055] The calculating unit 310 may execute a step of acquiring a first variation fn(T-T0) for each order term when at least one order of gain βn is varied in the N-th order function. The calculating unit 310 may acquire, for each order term of the N-th order function, a rate of change in the output voltage when a code determining the gain βn is varied from G1 to G2, as the first variation fn(T-T0). The calculating unit 310 may acquire, for each order term of the N-th order function, a rate of change in the output voltage output via the same path (the inverting path 126 or the non-inverting path 125) when a code determining the gain βn is varied from G1 to G2, as the first variation fn(T-T0). For each order term, the calculating unit 310 may acquire, for the first variation fn(T-T0), a difference in output voltage per unit programmable gain code among the first amplifier 122, the second amplifier 135, and the third amplifier 145 in the control circuit 40.

[0056] The calculation section 310 may calculate the first fluctuation amount f1(T-T0) for the first order by dividing the difference between the output voltage of the third amplifier 145 when the gain is G1 and the output voltage of the third amplifier 145 when the gain is G2 by the difference between G1 and G2.

[0057] The calculation section 310 may calculate the first variation amount f3(T-T0) for the third order by dividing the difference between the output voltage of the second amplifier 135 when the gain is G1 and the output voltage of the second amplifier 135 when the gain is G2 by the difference between G1 and G2.

[0058] The calculation unit 310 may calculate the first fluctuation amount f4(T-T0) for the fourth order by dividing the difference between the output voltage of the first amplifier 122 when the gain is G1 (in this embodiment, the output of the non-inverting path 125) and the output voltage of the first amplifier 122 when the gain is G2 (in this embodiment, the output of the non-inverting path 125) by the difference between G1 and G2.

[0059] The calculation section 310 may acquire the first fluctuation amount fn(T−T0) of each degree term as shown in the following equation 3.

[0060]

number

[0061] Here, in Equation 3, fn(T-T0) represents the first fluctuation amount of the nth-order term at temperature T, G1 and G2 represent codes that determine the gain βn, VCOUT(G1) represents the output voltage corresponding to the nth-order term when the code that determines the gain βn is G1, and VCOUT(G2) represents the output voltage corresponding to the nth-order term when the code that determines the gain βn is G2.

[0062] Next, the calculation unit 310 calculates the offset voltage V off The calculation unit 310 calculates the offset voltage V (T) of the inverting path 126 of the control circuit 40 relative to the non-inverting path 125 for at least one degree of the N-th degree function. off The calculation unit 310 performs a step of acquiring an offset voltage V between the output of the inverting path 126 that inverts the output signal of the temperature compensation circuit of at least one degree of the N-th order function in the control circuit 40 and the output of the non-inverting path 125 that leaves the output signal non-inverted. off A step of obtaining (T) may be performed.

[0063] The calculation unit 310 calculates the difference between the output voltage output via the inverting path 126 and the output voltage output via the non-inverting path 125 when the gain βn is set to 0 as the offset voltage V off The calculation unit 310 may obtain the offset voltage V off (T) may be obtained by simulating the characteristics of the control circuit 40. off You may also ask for (T).

[0064]

number

[0065] Here, in equation 4, V off (T) denotes the offset voltage corresponding to the nth order (fourth order in this embodiment) term at temperature T, VCOUT(G1) denotes the output voltage output via the non-inverting path 125 when G1=0, which is the code that determines the gain βn, and VCOUT(G3) denotes the output voltage output via the inverting path 126 when G3=0, which is the code that determines the gain βn.

[0066] In step S450, if the temperature T is not the upper limit of the temperature compensation range (85 degrees in this embodiment) (No in FIG. 4), the setting device 50 changes the temperature T (for example, to the current temperature T+5 degrees) and returns to step S410. If the current temperature T is the upper limit of the temperature compensation range (Yes in FIG. 4), the setting device 50 proceeds to the next step S460, and in the subsequent steps, the offset voltage V off (T) is used to execute a step of setting the gain βn of each order of the N-th order function and the central temperature.

[0067] Through steps S400-S450, the setting device 50 calculates the control voltage V ccal、 The first fluctuation amount fn(T-T0) and the offset voltage V off The setting device 50 can acquire the acquired control voltage V ccal、 The first fluctuation amount fn(T-T0) of each order and the offset voltage V off From (T), we can obtain functions that show the relationship between temperature and voltage.

[0068] Figure 5 shows the relationship between temperature and control voltage V ccal 5, the vertical axis represents the voltage value and the horizontal axis represents the temperature. The setting device 50 controls the temperature and the control voltage V ccal It is possible to obtain a function that shows the relationship between V ccal An offset voltage may be applied to the

[0069] FIG. 6 shows the relationship between temperature and the first fluctuation amount fn(T-T0). In FIG. 6, the vertical axis represents the voltage value, and the horizontal axis represents the temperature. FIG. 6 shows the first fluctuation amount f1(T-T0) for the first order, the first fluctuation amount f3(T-T0) for the third order, and the first fluctuation amount f4(T-T0) for the fourth order. The setting device 50 can obtain a function showing the relationship between temperature and the first fluctuation amount fn(T-T0) as shown in FIG. 6 for each order.

[0070] Figure 7 shows the offset voltage V off 7 shows the relationship between the offset voltage V (T) and temperature. In FIG. 7, the vertical axis represents the voltage value, and the horizontal axis represents the temperature. FIG. 7 shows the output voltage VCOUT_A (which is expressed as 0V for simplicity, indicating AGND) output through the non-inverting path 125 when the gain G1 for the fourth order obtained in step S430 is 0, the output voltage VCOUT_B output through the non-inverting path 125 when G2=2, and the output voltage VCOUT_C ​​output through the inverting path 126 when G3=0, all plotted against the offset voltage V off The calculation unit 310 calculates the relationship between the temperature and the offset voltage V by subtracting VCOUT_C ​​from VCOUT_A at each temperature. off (T) and the offset voltage V off As shown in FIG. 7, (T) has temperature dependency.

[0071] In step S460, the calculation unit 310 calculates the first fluctuation amount fn(T−T0) and the offset voltage V off (T), the calculation unit 310 determines the optimal value of the gain β of each degree of the Nth-order function and the optimal value of the central temperature by, for example, the least squares method. Assuming that the inversion path 126 is used, the calculation unit 310 determines the optimal value of the offset voltage V off Considering (T), the optimal value of the gain βn of each order of the Nth-order function, the optimal value of the central temperature, and assuming that a non-inverting path 125 is used, the offset voltage V off The optimum value of the gain βn of each degree of the N-th order function and the optimum value of the central temperature when (T) is not taken into consideration may be determined.

[0072] The calculation unit 310 calculates a first set of candidate values ​​for the gain βn of each degree of the N-th order function and the central temperature when generating the control voltage, assuming that the control voltage is generated via the inversion path 126 of the control circuit 40, as the offset voltage V off The step of determining may be performed using (T). A method for determining the first candidate value set will now be described.

[0073] The calculating section 310 may execute a step of generating a first function by multiplying a voltage according to temperature by a gain βn for each order of the N-th order function. For example, the calculating section 310 may generate the first function by multiplying a second fluctuation amount fn(T-T0-ΔT)′ obtained by shifting a first fluctuation amount fn(T-T0), which is a voltage according to temperature, by ΔT in the temperature direction, by the gain βn for each order.

[0074] The calculation unit 310 may acquire a second variation fn(T-T0-ΔT)' for each order term when the temperature is shifted by a shift amount ΔT, for the relationship between the temperature and a first variation fn(T-T0) for each order term of an N-th order function in which the central temperature is the initial value T0. The calculation unit 310 may acquire a second variation fn(T-T0-ΔT)' for each order term when the temperature is shifted by a shift amount ΔT, for each order term, for the relationship between the temperature and the first variation fn(T-T0) for each order term of an N-th order function in which the central temperature is the initial value T0. The second variation fn(T-T0-ΔT)' is obtained by adding the shift amount ΔT to the initial value T0 in the function of the first variation fn(T-T0) for each order term of Equation 3.

[0075] Fig. 8 shows an example in which the first fluctuation amount f3(T-T0) is shifted in the temperature direction by ΔT. In Fig. 8, the vertical axis represents the voltage value, and the horizontal axis represents the temperature of the voltage-controlled oscillator 20. In Fig. 8, the first fluctuation amount f3(T-T0) (i.e., the same as that shown in Fig. 6) is shown by a dashed line, and the second fluctuation amount f3(T-T0-ΔT)' obtained by shifting the first fluctuation amount f3(T-T0) in the temperature axis direction by the shift amount ΔT is shown by a solid line.

[0076] Fig. 9 shows an example in which the first fluctuation amount f4(T-T0) is shifted in the temperature direction. In Fig. 10, the vertical axis represents the voltage value, and the horizontal axis represents the temperature of the voltage-controlled oscillator 20. In Fig. 9, the first fluctuation amount f4(T-T0) (i.e., the same as that shown in Fig. 6) is shown by a dashed line, and the second fluctuation amount f4(T-T0-ΔT)' obtained by shifting the first fluctuation amount f4(T-T0) in the temperature axis direction by a shift amount ΔT is shown by a solid line.

[0077] Next, the calculation unit 310 calculates the target characteristic (V ccal (T)) with an offset voltage V off The calculation unit 310 may perform a step of generating a second function incorporating the offset voltage V (T). off You may generate a second function by subtracting (T).

[0078] The calculation section 310 may generate basis functions for the inverse path 126 incorporating the first function and the second function, as shown in Equation 5.

[0079]

number

[0080] In number 5, V ccal (T) represents the control voltage at which the output frequency of the voltage-controlled oscillator 20 matches the target frequency at temperature T, and V off (T) indicates the offset voltage at temperature T, β0, β1, β3, and β4 indicate the gains of the 0th, 1st, 3rd, and 4th order terms, respectively, f1(T-T0-ΔT)' indicates the second fluctuation amount in the 1st order term, f3(T-T0-ΔT)' indicates the second fluctuation amount in the 3rd order term, and f4(T-T0-ΔT)' indicates the second fluctuation amount in the 4th order term.

[0081] The calculation unit 310 may execute a step of determining a first set of candidate values ​​of the gain βn of each order of the N-th order function and the central temperature so that the difference between the first function and the second function is less than a predetermined threshold (for example, a minimum). The calculation unit 310 may perform a step of determining a first set of candidate values ​​of the gain βn of each order of the N-th order function and the central temperature so that the difference between the first function and the second function is less than a predetermined threshold (for example, a minimum). The calculation unit 310 may perform a step of determining a first set of candidate values ​​of the gain βn of each order of the N-th order function and the central temperature so that the difference between the first function and the second function is less than a predetermined threshold (for example, a minimum). off The calculation section 310 may calculate the difference between the target characteristic including (T) and the center temperature (initial value+shift amount ΔT) corresponding to the smallest difference among the calculated differences and the gain βn of each order, as a first set of candidate values ​​when it is assumed that the inversion path 126 is used.

[0082] FIG. 10 shows the offset voltage V off 10 shows an example of calculating the maximum value of the difference between the first function and the second function using a code that determines the gain βn of the N-th order function and a shift amount ΔT from the initial value of the core temperature when (T) is incorporated into the target characteristics. FIG. 10 shows some combinations of a plurality of shift amounts ΔT and codes that determine the gain βn used in the difference calculation. The calculation unit 310 calculates the value of the first function calculated using a combination of the gain βn for each of the shift amounts ΔT = -0.5, 0, +0.5, for example, by the least squares method using Equation 5, and the offset voltage V off Target characteristics (V ccal (T)-V off 10, the calculation unit 310 may determine the combination of β4 -> -9, β3 -> 6, β1 -> 20, β0 -> 10, and central temperature = 28.5 degrees (initial value 28 degrees + 0.5 degrees), which has the smallest difference of 1.6, as the first candidate value set. Note that if the code is negative, it means that the coefficient is negative.

[0083] Next, the calculation unit 310 may perform a step of determining a second set of candidate values ​​for the gain βn of each order of the Nth-order function and the central temperature when generating a control voltage, assuming that the control voltage is generated via the non-inverting path 125 of the control circuit 40. A method for determining the second set of candidate values ​​will be described below.

[0084] The calculation unit 310 may generate the basis functions in the same manner as in the case of using the inversion path 126 described above, except that the offset voltage V off The calculation unit 310 may generate a basis function without incorporating the gain βn (T). The calculation unit 310 may execute a step of generating a first function by multiplying a voltage according to temperature by a gain βn at each order of the N-th order function. The calculation unit 310 may generate a basis function by multiplying a voltage according to temperature by a gain βn (T) at each order of the N-th order function. ccal The calculation unit 310 may generate a basis function incorporating the following equation (6):

[0085]

number

[0086] In equation 6, V ccal (T) indicates the control voltage at which the output frequency of the voltage-controlled oscillator 20 matches the target frequency at temperature T, β0, β1, β3, and β4 indicate the gains of the 0th, 1st, 3rd, and 4th order terms, respectively, f1(T-T0-ΔT)' indicates the second fluctuation amount in the 1st order term, f3(T-T0-ΔT)' indicates the second fluctuation amount in the 3rd order term, and f4(T-T0-ΔT)' indicates the second fluctuation amount in the 4th order term.

[0087] The calculation unit 310 may determine a second set of candidate values ​​for the gain βn of each order of the N-th function and the central temperature so that the difference between the first function and the target characteristic of the control circuit 40 is less than a predetermined threshold (for example, the minimum). The calculation unit 310 may calculate the difference between the target characteristic and a value calculated by substituting a combination of the gain βn of each order for each of multiple shift amounts ΔT from the initial value of the central temperature in Equation 6. As a result, the calculation unit 310 may determine a second set of candidate values ​​for the central temperature (initial value+shift amount ΔT) and the gain βn of each order corresponding to the smallest difference among the multiple calculated differences, assuming that the non-inverting path 125 is used.

[0088] FIG. 11 shows the offset voltage V off11 shows an example in which the maximum value of the difference between the first function and the target characteristic is calculated using a code for determining the gain βn of the N-th order function and a shift amount ΔT from the initial value of the core temperature when (T) is not incorporated into the target characteristic. FIG. 11 shows some combinations of a plurality of shift amounts ΔT and codes for determining the gain βn used in the difference calculation. The calculation unit 310 uses Equation 6, for example, by the least squares method, to calculate the value of the first function calculated using combinations of gain βn for each of the shift amounts ΔT = -0.5, 0, +0.5, for example, and the target characteristic (V ccal 11, the calculation unit 310 may determine the combination of β4->-9, β3->6, β1->21, β0->10, and central temperature=28.5°C (initial value 28°C+0.5°C), which has the smallest difference of 1.8, as the second candidate value set.

[0089] In step S470, the setting device 50 sets the center temperature and gain β of the N-th order function in the control circuit 40. The calculation unit 310 may determine the center temperature and gain βn to be set from the first set of candidate values ​​and the second set of candidate values. If the gain βn of the order corresponding to the inversion path 126 is a negative value in at least one of the first set of candidate values ​​and the second set of candidate values, the calculation unit 310 determines that the inversion path 126 must be used and that the offset voltage V off On the other hand, if the gain βn of the order corresponding to the inverting path 126 is a positive value in at least one of the first and second candidate value sets, the calculation unit 310 determines that the non-inverting path 125 is used and that the offset voltage V off Since (T) does not need to be taken into consideration, the second set of candidate values ​​may be determined as the final setting values. In this embodiment, the calculation unit 310 may determine the first set of candidate values ​​as the final setting values ​​because the fourth-order gain β4 corresponding to the inversion path 126 is a negative value in at least one of the first set of candidate values ​​and the second set of candidate values.

[0090] The output unit 320 may output the determined final setting value to the voltage-controlled oscillator 20 to set it. The output unit 320 may set the gain βn in the amplifiers of each order and the zeroth-order temperature compensation circuit 150, and set a voltage corresponding to the center temperature in the input offset supplying unit 100. When the gain β4 is a negative value, the output unit 320 may set the absolute value of the gain β4 in the first amplifier 122, and may configure the sign switching unit 124 to switch to the inverting path 126 by turning off the first switch 127 and turning on the second switch 129.

[0091] According to this embodiment, the setting device 50 calculates the offset voltage V off The setting device 50 can set the optimum values ​​of the gain βn and the central temperature taking into account (T), thereby improving the accuracy of temperature compensation by the control circuit 40. In addition, the setting device 50 can set the optimum values ​​of the gain βn and the central temperature taking into account (T), thereby improving the accuracy of temperature compensation by the control circuit 40. off By using (T), the offset voltage V off It is possible to set a value that takes into account the temperature dependency of (T), improving the accuracy of temperature compensation over the entire compensation temperature range.

[0092] In step S440, the calculation unit 310 calculates the offset voltage V off (T) may be calculated using an output voltage where the gain β4 is not 0. For example, in step S430, the acquisition unit 300 acquires the output voltage via the non-inverting path 125 and the output voltage via the inverting path 126 when the gain β4 is d (d>0), and in step S440, the calculation unit 310 calculates the offset voltage V off It may also be calculated as (T).

[0093] Next, a second embodiment of the setting operation of the setting device 50 will be described. In the second embodiment, the setting device 50 may perform the setting operation in the same manner as in the first embodiment. However, in the second embodiment, the calculation section 310 calculates the offset voltage V offThe offset voltage V is calculated using the third candidate value set calculated using the basis function that does not include (T). off The optimum value is set using a basis function including (T). The second embodiment will be described below, focusing on the differences from the first embodiment.

[0094] In steps S400-S450, the setting device 50 may perform the setting operation in the same manner as in the first embodiment. In step S460, the calculation unit 310 may perform a step of generating a first function by multiplying a voltage (second fluctuation amount fn(T-T0-ΔT)') according to temperature by a gain βn at each degree of the N-th order function in the same manner as in the first embodiment. The calculation unit 310 calculates the offset voltage V off The calculation unit 310 may generate the basis functions without incorporating the target characteristic (V ccal The calculation unit 310 may perform a step of determining a third set of candidate values ​​of the gain βn of each order of the N-th function and the central temperature so that the difference between the offset voltage V (T) and the first function is less than a predetermined threshold (for example, a minimum). The calculation unit 310 may determine the third set of candidate values ​​using Equation 6, as in the first embodiment. Therefore, the third set of candidate values ​​is off This is the optimal value when (T) is not incorporated (i.e., when the non-inverting path 125 is assumed to be used), and may be the same value as the second set of candidate values.

[0095] Here, in the third candidate value set, when the gain βn of the order corresponding to the inversion path 126 (where the inversion path 126 is arranged) is a negative value, the calculation unit 310 calculates the offset voltage V off (T) is newly used to calculate the optimal values ​​of the central temperature and the gain βn using the third candidate value set. On the other hand, if the gain βn of the order corresponding to the inversion path 126 is a positive value, the calculation unit 310 may determine the third candidate value set as the final set of setting values. In this embodiment, if the fourth-order gain β4 is a negative value in the third candidate value set, the calculation unit 310 may determine the offset voltage V off Basis functions incorporating (T) may be used to calculate optimal values ​​for the central temperature and gain βn.

[0096] Next, when the gain βn of the order corresponding to the inversion path 126 is a negative value, the calculation unit 310 adds an offset voltage V off The calculation unit 310 may perform a step of generating a third function incorporating the offset voltage V (T) into the first function. off (T) to generate the third function. The calculation section 310 may generate the basis functions shown in Equation 7 using the third function.

[0097]

number

[0098] In equation 7, V off (T) is the offset voltage at temperature T, and V ccal (T) indicates the control voltage at which the output frequency of the voltage-controlled oscillator 20 matches the target frequency at temperature T, β0, β1, β3, and β4 indicate the gains of the 0th, 1st, 3rd, and 4th order terms, respectively, f1(T-T0-ΔT)' indicates the second fluctuation amount in the 1st order term, f3(T-T0-ΔT)' indicates the second fluctuation amount in the 3rd order term, and f4(T-T0-ΔT)' indicates the second fluctuation amount in the 4th order term.

[0099] The calculation unit 310 may execute a step of setting the gain β of each degree of the N-th order function and the central temperature using the third candidate value set so that the difference between the third function and the target characteristic of the control circuit 40 is less than a predetermined threshold (for example, a minimum). The calculation unit 310 calculates the difference between the third function shown in Equation 7 and the target characteristic (V ccal The gain βn of each order and the central temperature may be determined using the third candidate value set so that the difference between the

[0100] The calculation unit 310 may, for example, substitute the gain βn of each order and the central temperature, based on the gain βn of each order of the third candidate value set and the central temperature, into a third function to calculate the difference between the third function and the target characteristic of the control circuit 40. The calculation unit 310 may substitute a plurality of shift amounts ΔT (candidate values ​​±c of the shift amount ΔT (c=0.5 degrees and 0 degrees, as an example)) based on the candidate value of the central temperature of the third candidate value set (initial value+candidate value of the shift amount ΔT) and a plurality of codes for determining the gain βn based on the candidate value βn of the gain (±m (m=1, 2, 3, as an example) centered on the code for determining the gain candidate value βn) into the third function, and calculate the target characteristic (V ccal The calculation unit 310 may calculate a combination of the code and central temperature (initial value T0 + shift amount ΔT) that determines the gain βn and minimizes the difference from the target characteristic. In this case, the calculation unit 310 can calculate the correspondence relationship between the combination of the code that determines the shift amount ΔT and the gain βn, and the difference from the target characteristic, as shown in FIG. 12. FIG. 12 is a part of a diagram in which a third candidate value set is set as β4 ⇒ -9, β3 ⇒ 6, β1 ⇒ 21, β0 ⇒ 10, and the central temperature = 28.5 degrees (initial value 28 degrees + 0.5 degrees), and the code and central temperature that determine the optimal gain βn for each order are found from a brute force search based on this third candidate value set.

[0101] For example, the calculation unit 310 may calculate the difference between the target characteristic and each of the candidates in a round-robin search as shown in Fig. 12, and determine the combination of the code determining the gain βn of each order of the Nth-order function and the shift amount ΔT that results in the smallest difference as the final setting value. The output unit 320 may output the combination of the central temperature (initial value T0 + shift amount ΔT) and the code determining the gain βn, which is the final setting value, to the control circuit 40 to set it. In the case of Fig. 12, the control circuit 40 may set the condition that minimizes the difference at 1.6.

[0102] According to this embodiment, the offset voltage V off The setting value can be calculated using a basis function incorporating (T). offA candidate value is determined in advance using a basis function that does not incorporate (T), and only when the coefficient of β4 of the candidate value is negative, the offset voltage V off By calculating the setting value using a basis function that incorporates (T), the optimal setting value can be determined efficiently.

[0103] 13 shows a first modified example of the temperature compensated oscillator 10 according to this embodiment. The temperature compensated oscillator 10 has the same configuration as the temperature compensated oscillator 10 in FIG. 1 and performs the same operation, except that a first amplifier 122 is connected after the code switching unit 124. Below, the temperature compensated oscillator 10 of the first modified example will be described, focusing on the differences from the temperature compensated oscillator 10 in FIG. 1.

[0104] The code switching unit 124 is connected between the fourth-order temperature compensation circuit 120 and the first amplifier 122. The code switching unit 124 has an inverting path 126 and a non-inverting path 125 between the fourth-order temperature compensation circuit 120 and the first amplifier 122. The code switching unit 124 may switch the path through which the signal output by the fourth-order temperature compensation circuit 120 passes, between the non-inverting path 125 and the inverting path 126. The code switching unit 124 may have a configuration similar to that of the code switching unit 124 of the temperature compensated oscillator 10 in FIG. 1 and perform a similar operation.

[0105] The first amplifier 122 is connected to the control voltage supply circuit 160. The first amplifier 122 may amplify the signal output by the code switching unit 124 and output the amplified signal to the control voltage supply circuit 160. The first amplifier 122 may have a configuration similar to that of the first amplifier 122 of the temperature compensated oscillator 10 in FIG. 1 and perform a similar operation.

[0106] In the control circuit 40 of this modified example, the output of the code switching unit 124 is amplified by the first amplifier 122, so the setting device 50 sets the offset voltage V off (T) may be used to set the central temperature and gain β4. A third example of the setting operation for setting the set value of the temperature compensated oscillator 10 of the first modified example by the setting device 50 will now be described.

[0107] In the third embodiment, the setting device 50 may set the gain βn and the central temperature in the same manner as in the setting operation of the first embodiment in Fig. 4. However, in step S430, the acquisition unit 300 may acquire the output voltage via the non-inverting path 125 and the output voltage via the inverting path 126 when the gain β4 = d (d > 0). In step S440, the calculation unit 310 calculates the offset voltage V by dividing the sum of the output voltage via the non-inverting path 125 (the output voltage of the first amplifier 122) and the output voltage via the inverting path 126 (the output voltage obtained by inverting the output of the fourth-order temperature compensation circuit 120 and amplifying it with the first amplifier 122) by d. off You may calculate the value of (T).

[0108] The calculation unit 310 calculates the offset voltage V off (T) may be incorporated into Equation 5 or Equation 7. For example, the calculation unit 310 may use the offset voltage V off Instead of (T), the offset voltage multiplied by the gain β4 ((β4 × V off The calculation unit 310 may incorporate β4×V off The optimum values ​​of the gain βn of the N-th order function and the central temperature may be set using the basis functions of Equation 5 or Equation 7 incorporating (T).

[0109] According to this embodiment, even when the inverting path 126 is placed in the front stage of the amplifier, it is possible to calculate a highly accurate set value using an offset voltage according to the gain of the corresponding amplifier.

[0110] In the above embodiment, the case where the control circuit 40 has one code switching unit 124 has been described, but this is not limited to this, and even if the control circuit 40 has multiple code switching units 124, the setting value can be set using the setting method of this embodiment.

[0111] 14 shows a second modified example of the temperature-compensated oscillator 10 according to this embodiment. The temperature-compensated oscillator 10 of the second modified example has the same configuration as the temperature-compensated oscillator 10 of FIG. 1 and performs the same operation, except that it includes multiple code switching units. The following describes the temperature-compensated oscillator 10 of the second modified example, focusing on the differences from the temperature-compensated oscillator 10 of FIG. 1.

[0112] The first code switching unit 500 may have a configuration similar to that of the code switching unit 124 of FIG. 1 and may perform a similar operation. The second code switching unit 510 is connected between the second amplifier 135 and the control voltage supply circuit 160. The second code switching unit 510 may switch the path between the second amplifier 135 and the control voltage supply circuit 160 between an inverting path and a non-inverting path. The second code switching unit 510 may have a configuration similar to that of the code switching unit 124 of FIG. 1 and may perform a similar operation. The third code switching unit 520 is connected between the third amplifier 145 and the control voltage supply circuit 160. The third code switching unit 520 may switch the path between the third amplifier 145 and the control voltage supply circuit 160 between an inverting path and a non-inverting path. The third code switching unit 520 may have a configuration similar to that of the code switching unit 124 of FIG. 1 and may perform a similar operation. The first code switching unit 500, the second code switching unit 510, and the third code switching unit 520 may each output a signal via an inverting path when the gain βn of the corresponding order is a negative value, and may output a signal via a non-inverting path when the gain βn of the corresponding order is a positive value. Below, a fourth example of a setting operation in which the setting device 50 sets the setting value of the temperature compensated oscillator 10 of the second modified example will be described.

[0113] In the fourth embodiment, the setting device 50 may set the setting values ​​of the temperature compensated oscillator 10 of the second modified example, as in the first embodiment. However, the setting device 50 may determine candidate values ​​for each of a plurality of combinations of inversion paths. The following describes the fourth embodiment, focusing on the operations that differ from the first embodiment.

[0114] In step S440, the calculation unit 310 calculates, for each of the multiple inverting paths of the control circuit 40, the offset voltage Voff For example, the calculation unit 310 may perform a step of acquiring the offset voltage V (T) for each order corresponding to the inverted path, as in the first embodiment. off (T) may be obtained.

[0115] The calculation unit 310 calculates the difference between the output voltage output via the inverting path and the output voltage output via the non-inverting path when the gain βn is set to 0 for each order as the offset voltage V off For example, the calculation unit 310 may calculate the difference between the output voltage output through the inverting path 126 and the output voltage output through the non-inverting path 125 in the first code switching unit 500 when the gain β4 is set to 0 as the offset voltage V off4 The calculation unit 310 may obtain the offset voltage V (T) (hereinafter also referred to as a fourth-order offset voltage) by calculating the difference between the output voltage output through the inverting path and the output voltage output through the non-inverting path in the second code switching unit 510 when the gain β3 is set to 0. off3 The calculation unit 310 may obtain the offset voltage V (T) (hereinafter also referred to as a third-order offset voltage) by calculating the difference between the output voltage output through the inverting path and the output voltage output through the non-inverting path in the third code switching unit 520 when the gain β1 is set to 0. off1 The acquisition unit 300 may acquire the offset voltage V for each order by repeating steps S410 to S450. off (T) may be obtained at multiple temperatures.

[0116] In step S460, the calculation unit 310 may execute a step of determining a fourth set of candidate values ​​of the gain βn of each degree of the N-th order function and the central temperature for each of a plurality of combinations of the inverted path and the non-inverted path used to generate the control voltage. The calculation unit 310 may execute a step of determining a fourth set of candidate values ​​of the gain βn of each degree of the N-th order function and the central temperature for each of a plurality of combinations of the inverted path and the non-inverted path used to generate the control voltage. off_sum (T) may be calculated.

[0117] The calculation unit 310 calculates the offset voltage V corresponding to the inverting path used to generate the control voltage for each combination of the inverting path and the non-inverting path. off (T) is the total value at each temperature, V off_sum For example, when an output voltage from a combination of the inverting path 126 in the first code switching unit 500, the non-inverting path 125 in the second code switching unit 510, and the non-inverting path 125 in the third code switching unit 520 is used to generate a control voltage, the calculating unit 310 may calculate the fourth-order offset voltage V off4 (T) is the offset voltage V off_sum When the output voltage from the combination of the inverting path 126 in the first code switching unit 500, the inverting path 126 in the second code switching unit 510, and the non-inverting path 125 in the third code switching unit 520 is used to generate the control voltage, the calculation unit 310 calculates the fourth-order offset voltage V off4 (T) and the third offset voltage V off3 The total value of (T) is the offset voltage V off_sum When the output voltage from the combination of the inverting path 126 in the first code switching unit 500, the inverting path 126 in the second code switching unit 510, and the inverting path 126 in the third code switching unit 520 is used to generate the control voltage, the calculating unit 310 calculates the fourth-order offset voltage V off4 (T) and the third offset voltage V off3 (T) and primary offset voltage V off1 The sum of (T) and (T) is the offset voltage V off_sum The calculation unit 310 may calculate the total value for other combinations in the same manner.

[0118] The calculation unit 310 calculates the offset voltage V off_sum (T) to V off (T) into the basis functions, a plurality of basis functions corresponding to each combination of the inversion path 126 and the non-inversion path 125 may be generated. off (T) is the calculated total value, V off_sum (T) may be incorporated into each.

[0119] The calculation unit 310 calculates the offset voltage V off_sum (T) to V off Similarly to step S460, multiple fourth candidate value sets may be determined using multiple basis functions incorporated as (T). In addition, when performing calculations assuming that all of the offset voltages V off Since (T) is zero, the second candidate value set calculated using Equation 6 may be determined as one of the fourth candidate value sets.

[0120] In step S470, the setting device 50 may execute a step of setting one of the plurality of fourth candidate value sets as the gain βn of each order of the N-th order function and the central temperature. The calculation unit 310 may determine, from the plurality of fourth candidate value sets, a fourth candidate value set to be used as the setting value according to the sign of the gain βn. The calculation unit 310 may determine, as the final setting value, a fourth candidate value set corresponding to a combination in which, in at least one of the plurality of fourth candidate value sets, the order in which the sign of the gain βn is negative is an inversion path and the order in which the sign of the gain βn is positive is a non-inversion path.

[0121] The output section 320 may output the set value determined by the calculation section 310 to the control circuit 40 to set it.

[0122] According to the above embodiment, the setting device 50 can calculate a setting value that further improves the accuracy of temperature compensation when the control circuit 40 uses inversion paths of multiple orders.

[0123] In the fourth embodiment, the calculation unit 310 calculates the offset voltage V off Alternatively, a third candidate value set may be determined in which (T) is not taken into consideration, and one combination of an inverted path and a non-inverted path may be determined according to the sign of the gain βn of each order in the third candidate value set. In this case, in step S440, the calculation unit 310 calculates the offset voltage V off_sumFor example, the calculation section 310 may perform a step of generating a third function by incorporating the above-mentioned (T) into the first function. off_sum (T) and obtain the offset voltage V off_sum (T) to V of number 7 off (T). In step S460, the calculation unit 310 may use the third candidate value set to execute a step of setting the gain of each degree of the N-th order function and the central temperature so that the difference between the third function and the target characteristic of the control circuit is less than a predetermined threshold. For example, the calculation unit 310 may set the offset voltage V off_sum Using equation 7 with (T) substituted, the optimal gain βn and core temperature can be set from among the candidates based on the third candidate value set. This eliminates the need to calculate multiple fourth candidate value sets, improving calculation efficiency.

[0124] The setting operations of the first, second, third, and fourth embodiments can be combined with one another.

[0125] The gains G1, G2, G3, the predetermined threshold, the shift amount ΔT, the initial value of the core temperature, and the like used in the setting device 50 may be acquired in advance by the acquisition unit 300 through user input.

[0126] Various embodiments of the present invention may be described with reference to flowcharts and block diagrams, where the blocks may represent (1) stages of a process in which operations are performed or (2) sections of an apparatus responsible for performing the operations. Particular stages and sections may be implemented by dedicated circuitry, programmable circuitry provided with computer-readable instructions stored on a computer-readable medium, and / or a processor provided with computer-readable instructions stored on a computer-readable medium. Dedicated circuitry may include digital and / or analog hardware circuitry, and may include integrated circuits (ICs) and / or discrete circuits. Programmable circuitry may include reconfigurable hardware circuitry, including logical AND, OR, XOR, NAND, NOR, and other logical operations, flip-flops, registers, memory elements such as field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), and the like.

[0127] A computer-readable medium may include any tangible device capable of storing instructions that are executed by an appropriate device, such that the computer-readable medium having instructions stored thereon comprises an article of manufacture containing instructions that can be executed to create means for performing the operations specified in the flowcharts or block diagrams. Examples of computer-readable media may include electronic, magnetic, optical, electromagnetic, and semiconductor storage media. More specific examples of computer-readable media may include floppy disks, diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), electrically erasable programmable read-only memory (EEPROM), static random access memory (SRAM), compact disc read-only memory (CD-ROM), digital versatile disc (DVD), Blu-ray disc, memory stick, integrated circuit card, and the like.

[0128] The computer readable instructions may include either assembler instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state-setting data, or source or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk®, JAVA®, C++, etc., and conventional procedural programming languages ​​such as the “C” programming language or similar programming languages.

[0129] The computer-readable instructions may be provided to a processor or programmable circuitry of a programmable data processing apparatus, such as a general-purpose computer, special-purpose computer, or other computer, either locally or over a wide-area network (WAN) such as a local area network (LAN), the Internet, etc., which executes the computer-readable instructions to create means for performing the operations specified in the flowcharts or block diagrams. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers, etc.

[0130] 15 illustrates an example of a computer 2200 in which aspects of the present invention may be embodied, in whole or in part. Programs installed on the computer 2200 may cause the computer 2200 to function as or perform operations associated with an apparatus or one or more sections of the apparatus according to embodiments of the present invention, and / or to perform a process or steps of a process according to embodiments of the present invention. Such programs may be executed by the CPU 2212 to cause the computer 2200 to perform specific operations associated with some or all of the blocks in the flowcharts and block diagrams described herein.

[0131] A computer 2200 according to this embodiment includes a CPU 2212, a RAM 2214, a graphics controller 2216, and a display device 2218, which are interconnected by a host controller 2210. The computer 2200 also includes input / output units such as a communication interface 2222, a hard disk drive 2224, a DVD-ROM drive 2226, and an IC card drive, which are connected to the host controller 2210 via an input / output controller 2220. The computer also includes legacy input / output units such as a ROM 2230 and a keyboard 2242, which are connected to the input / output controller 2220 via an input / output chip 2240.

[0132] The CPU 2212 operates according to programs stored in the ROM 2230 and RAM 2214, thereby controlling each unit. The graphics controller 2216 acquires image data generated by the CPU 2212 into a frame buffer or the like provided in the RAM 2214 or into the graphics controller 2216 itself, and causes the image data to be displayed on the display device 2218.

[0133] The communications interface 2222 communicates with other electronic devices via a network. The hard disk drive 2224 stores programs and data used by the CPU 2212 in the computer 2200. The DVD-ROM drive 2226 reads programs or data from the DVD-ROM 2201 and provides the programs or data to the hard disk drive 2224 via the RAM 2214. The IC card drive reads programs and data from an IC card and / or writes programs and data to an IC card.

[0134] The ROM 2230 stores therein a boot program or the like that is executed by the computer 2200 upon activation, and / or programs that depend on the hardware of the computer 2200. The input / output chip 2240 may also connect various input / output units to the input / output controller 2220 via a parallel port, a serial port, a keyboard port, a mouse port, etc.

[0135] The programs are provided by a computer-readable medium such as a DVD-ROM 2201 or an IC card. The programs are read from the computer-readable medium, installed in the hard disk drive 2224, RAM 2214, or ROM 2230, which are also examples of computer-readable media, and executed by the CPU 2212. Information processing described in these programs is read by the computer 2200, and brings about cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be configured by realizing information manipulation or processing in accordance with the use of the computer 2200.

[0136] For example, when communication is performed between the computer 2200 and an external device, the CPU 2212 may execute a communication program loaded into the RAM 2214 and instruct the communication interface 2222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 2212, the communication interface 2222 reads transmission data stored in a transmission buffer processing area provided in the RAM 2214, the hard disk drive 2224, the DVD-ROM 2201, or a recording medium such as an IC card, and transmits the read transmission data to the network, or writes reception data received from the network to a reception buffer processing area or the like provided on the recording medium.

[0137] The CPU 2212 may also cause all or a necessary portion of a file or database stored on an external recording medium such as the hard disk drive 2224, the DVD-ROM drive 2226 (DVD-ROM 2201), an IC card, etc. to be read into the RAM 2214, and perform various types of processing on the data on the RAM 2214. The CPU 2212 then writes back the processed data to the external recording medium.

[0138] Various types of information, such as various types of programs, data, tables, and databases, may be stored on the recording medium and may undergo information processing. The CPU 2212 may perform various types of processing on data read from the RAM 2214, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequences of the programs, and write the results back to the RAM 2214. The CPU 2212 may also search for information in a file, database, etc. on the recording medium. For example, if multiple entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored on the recording medium, the CPU 2212 may search for an entry that matches a condition specified by the attribute value of the first attribute from among the multiple entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0139] The above-described programs or software modules may be stored in a computer-readable medium on or near the computer 2200. A recording medium such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet can also be used as a computer-readable medium, thereby providing the programs to the computer 2200 via the network.

[0140] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0141] It should be noted that the execution order of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order. [Explanation of symbols]

[0142] 10 Temperature compensated oscillator 20 Voltage Controlled Oscillator 30 Temperature Sensor 40 Control circuit 50 Setting device 100 Input offset supply unit 110 Addition section 120 4th order temperature compensation circuit 122 First Amplifier 124 Code Switching Unit 126 Reverse Pass 125 Non-inverting Path 127 First Switch 128 Inverter Circuit 129 Second Switch 130 Third-order temperature compensation circuit 135 Second Amplifier 140 Primary temperature compensation circuit 145 Third Amplifier 150 0th order temperature compensation circuit 160 Control voltage supply circuit 300 Acquisition Department 310 Calculation Unit 320 Output Section 500 First code switching unit 510 Second code switching unit 520 Third code switching unit 2200 Computer 2201 DVD-ROM 2210 host controller 2212 CPU 2214 RAM 2216 Graphics Controller 2218 Display Device 2220 Input / Output Controller 2222 communication interface 2224 hard disk drive 2226 DVD-ROM drive 2230 ROM 2240 I / O chip 2242 keyboard

Claims

1. A method for setting an Nth-order function in a control circuit that applies a control voltage generated using the Nth-order function to a voltage-controlled oscillator, the method comprising: and setting a gain of each order of the Nth-order function and a central temperature of the voltage-controlled oscillator using an offset voltage of an inverting path of the control circuit relative to a non-inverting path for at least one order of the Nth-order function. How to set it up.

2. The step of setting the gain and the core temperature includes: determining, using the offset voltage, a first set of candidate values ​​for the gain of each degree of the Nth-order function and the central temperature when generating the control voltage assuming that the control voltage passes through the inverting path of the control circuit; determining a second set of candidate values ​​for the central temperature and the gain of each order of the N-th order function when generating the control voltage assuming that it passes through the non-inverting path of the control circuit; and setting the central temperature and the gain of each degree of the Nth-order function using the first set of candidate values ​​and the second set of candidate values. The setting method according to claim 1 .

3. The step of determining the first set of candidate values ​​includes: generating a first function by multiplying a voltage according to temperature by the gain for each degree of the N-th order function; generating a second function that incorporates the offset voltage into a target characteristic of the control circuit; determining the first set of candidate values ​​of the gain of each order of the N-th order function and the central temperature such that the difference between the first function and the second function is less than a predetermined threshold value; The setting method according to claim 2 .

4. The step of determining the second set of candidate values ​​comprises: generating a first function by multiplying a voltage according to temperature by the gain for each degree of the N-th order function; determining the second set of candidate values ​​for the gain of each order of the N-th order function and the central temperature so that a difference between the first function and a target characteristic of the control circuit is less than a predetermined threshold value; The setting method according to claim 2 .

5. The step of setting the gain and the core temperature includes: generating a first function by multiplying a voltage according to temperature by the gain for each degree of the N-th order function; determining a third set of candidate values ​​for the gains of the N-th order functions and the central temperature such that a difference between the target characteristic of the control circuit and the first function is less than a predetermined threshold; generating a third function by incorporating the offset voltage into the first function; and setting the central temperature and the gain of each order of the N-th order function using the third candidate value set so that a difference between the third function and a target characteristic of the control circuit is less than a predetermined threshold value. The setting method according to claim 1 .

6. obtaining the offset voltage of an inverting path relative to a non-inverting path of the control circuit for at least one order of the N-th order function at a plurality of temperatures. The setting method according to claim 1 .

7. The step of obtaining the offset voltage includes: obtaining an offset voltage for each of a plurality of inverting paths of the control circuit relative to a non-inverting path at a plurality of temperatures; The step of setting the gain and the core temperature includes: determining a fourth set of candidate values ​​for the central temperature and the gain of each order of the N-th order function for each of a plurality of combinations of the inverted path and the non-inverted path used to generate the control voltage; and setting one of the plurality of fourth candidate value sets as the gain of each order of the N-th order function and the central temperature. The setting method according to claim 6.

8. The step of obtaining the offset voltage includes: obtaining an offset voltage for each of a plurality of inverting paths of the control circuit relative to a non-inverting path at a plurality of temperatures; The step of setting the gain and the core temperature includes: generating a first function by multiplying a voltage according to temperature by the gain for each degree of the N-th order function; determining a third set of candidate values ​​for the gains of the N-th order functions and the central temperature such that a difference between the target characteristic of the control circuit and the first function is less than a predetermined threshold; generating a third function by incorporating the offset voltages, which are added together according to the signs of the gains of the respective orders of the third candidate value set, into the first function; and setting the central temperature and the gain of each order of the N-th order function using the third candidate value set so that a difference between the third function and a target characteristic of the control circuit is less than a predetermined threshold value. The setting method according to claim 6.

9. acquiring, at a plurality of temperatures, a first variation amount of a term of each order when a gain of at least one order in the N-th order function is varied; The step of setting the gain and the core temperature includes: and setting the central temperature and the gain of each degree of the N-th order function based on the first variation amount and the offset voltage. The setting method according to claim 1 .

10. The step of obtaining the offset voltage includes: and obtaining, at a plurality of temperatures, the offset voltage between the output of the inverting path that inverts the output signal of the temperature compensation circuit of at least one degree of the N-th order function in the control circuit and the output of the non-inverting path that leaves the output signal non-inverted. The setting method according to claim 6.

11. A program for causing a computer to execute the setting method according to claim 1.

Images