JP2015211334A - Piezoelectric device with thermostat, and manufacturing method of piezoelectric device with thermostat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric device with a thermostat capable of performing a temperature compensation while taking influences of packaging into account.SOLUTION: An OCXO 1 includes: a TCXO 3 including a plurality of first terminals 25; a packaging substrate 17 including a plurality of second terminals 27 and a plurality of third terminals 29 connected with the plurality of first terminals 25 via a plurality of connection wires 31; a case 19 accommodating the TCXO 3; and a heater 21 capable of heating an atmosphere within the case 19. The plurality of first terminals 25 includes a first write terminal 25W capable of writing information specifying a temperature compensation amount into a ROM 43 of the TCXO 3. The plurality of third terminals 29 include a third write terminal 29W connected to the second write terminal 27W.

Description

  The present invention relates to a thermostatic chamber-equipped piezoelectric device and a method for manufacturing a thermostatic chamber-equipped piezoelectric device.

  A piezoelectric device having a thermostatic chamber is known. For example, Patent Document 1 discloses an oven controlled crystal oscillator (OCXO) in which a temperature compensated oscillator (TCXO: Temperature Compensated Crystal Oscillator) is housed in a thermostat.

  In the TCXO, the value of the parameter that defines the temperature compensation amount is determined by measuring the temperature characteristic of the oscillation signal output from the TCXO after completion of the packaging of the TCXO. Stored in the memory. Therefore, the temperature compensation amount of the TCXO takes into account the influence of manufacturing variations of the TCXO and the influence of the temperature difference between the vibration element (piezoelectric body) and the temperature sensor.

JP2013-211752A

  When a temperature compensated piezoelectric device such as TCXO is mounted on a circuit board, the specific modes of heat dissipation and / or heat absorption in each part of the temperature compensated piezoelectric device are different from those before mounting. As a result, the temperature difference between the piezoelectric body and the temperature sensor is also different from that before mounting. As a result, the value of the parameter that defines the temperature compensation amount written in the temperature compensated piezoelectric device is not an optimum value for the temperature compensated piezoelectric device after mounting.

  Therefore, it is desirable to provide a thermostatic chamber-equipped piezoelectric device and a method for manufacturing the same that can perform temperature compensation in consideration of mounting effects.

  The thermostatic chamber-equipped piezoelectric device according to one aspect of the present invention includes a temperature-compensated piezoelectric device having a plurality of first terminals, a plurality of second terminals connected to the plurality of first terminals, and the plurality of second terminals. A mounting base having a plurality of connection wirings extending from the terminals, a plurality of third terminals connected to the plurality of second terminals by the plurality of connection wirings, a case housing the temperature-compensated piezoelectric device, A temperature adjusting element capable of performing at least one of heating and cooling of the atmosphere in the case, and the plurality of first terminals write information defining a temperature compensation amount in a memory of the temperature compensated piezoelectric device A possible first write terminal, the plurality of third terminals including a third write terminal connected to the first write terminal;

  Preferably, the thermostatic chamber-equipped piezoelectric device further includes a plurality of external terminals connected to the plurality of third terminals and exposed to the outside of the case, wherein the plurality of external terminals are the third write terminals. Including an external write terminal connected to.

  Preferably, the temperature-compensated piezoelectric device is located on a piezoelectric body, an integrated circuit element including a temperature sensor used for temperature compensation, a first recess that houses the piezoelectric body, and a back surface of the first recess. And an element mounting member having a second recess for accommodating the integrated circuit element.

  The method for manufacturing a thermostatic chamber-equipped piezoelectric device according to an aspect of the present invention includes a temperature compensated piezoelectric device having a plurality of first terminals, a plurality of second terminals connected to the plurality of first terminals, and the plurality of the plurality of first terminals. Mounting on a mounting substrate having a plurality of connection wires extending from the second terminal and a plurality of third terminals connected to the plurality of second terminals by the plurality of connection wires, and mounting on the mounting substrate And measuring the temperature characteristic of the temperature compensated piezoelectric device via any of the plurality of third terminals, and based on the measurement result of the measurement step, the temperature in the memory of the temperature compensated piezoelectric device is measured. And a writing step of writing information defining the compensation amount.

  Preferably, in the writing step, the information is written into the memory via any one of the plurality of third terminals.

  Preferably, in the manufacturing method, the temperature-compensated piezoelectric device is accommodated in a case while exposing a plurality of external terminals connected to the plurality of third terminals after the mounting step and before the measuring step. And the measuring step measures the temperature characteristics of the temperature-compensated piezoelectric device accommodated in the case via any of the plurality of external terminals, and the writing step The information is written into the memory via any other external terminal.

  According to the above configuration or procedure, it is possible to perform temperature compensation in consideration of mounting effects.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a schematic configuration of a crystal oscillator with a thermostatic bath according to an embodiment of the present invention, partially broken away. Sectional drawing in the II-II line of FIG. 3A is a bottom view of the TCXO included in the OCXO of FIG. 1, and FIG. 3B is a top view of the mounting substrate included in the OCXO of FIG. The block diagram which shows schematic structure of the signal processing system of OCXO of FIG. The flowchart which shows the procedure of the manufacturing method of OCXO of FIG. The flowchart which shows the procedure of the modification of the manufacturing method of OCXO of FIG.

  Hereinafter, OCXO according to an embodiment of the present invention will be described with reference to the drawings. Note that the drawings used in the following description are schematic, and the dimensional ratios and the like on the drawings do not necessarily match the actual ones.

  The OCXO may be set in any direction upward or downward, but hereinafter, for convenience, terms such as an upper surface and a lower surface are defined by defining the orthogonal coordinate system xyz and setting the positive side in the z direction upward. Shall be used.

  FIG. 1 is a perspective view showing a schematic configuration of an OCXO 1 according to an embodiment of the present invention, with a part thereof broken. 2 is a cross-sectional view taken along the line II-II in FIG.

  The OCXO 1 includes, for example, a TCXO 3 and a thermostatic chamber 5 for maintaining an atmosphere around the TCXO 3 at a predetermined temperature and mediating electrical connection between the TCXO 3 and an external device.

  The TCXO 3 includes, for example, an element mounting member 7, a vibration element 9 (FIG. 2) and an IC 11 (FIG. 2) mounted on the element mounting member 7, and a lid body 13 for sealing the vibration element 9. Have.

  The element mounting member 7 includes, for example, an insulating member 15 and various conductors provided on the surface or inside of the insulating member 15.

  As shown in FIG. 2, the insulating member 15 has a first recess 15 a that opens upward and accommodates the vibration element 9, and a second recess 15 b that opens downward and accommodates the IC 11. In another aspect, the insulating member 15 includes a substrate portion 15c, a first frame portion 15d positioned on one main surface of the substrate portion 15c, and a second frame portion positioned on the other main surface of the substrate portion 15c. 15e. The insulating member 15 is formed by stacking a plurality of layered members made of ceramic such as alumina, for example.

  Various conductors of the element mounting member 7 are provided on the bottom surface of the first recess 15a, for example, and a pair of element mounting pads (not shown) for mounting the vibration element 9 on the bottom surface of the second recess 15b. A plurality of IC mounting pads (not shown) for mounting the IC 11 and provided on the lower surface of the second frame portion 15e, and a plurality of first terminals 25 for inputting / outputting signals to / from the TCXO 3 (see FIG. 3) Wiring (not shown) for connecting a pair of element mounting pads and two of the plurality of IC mounting pads, the rest of the plurality of IC mounting pads, and the plurality of first terminals 25. Wiring (not shown) for connecting. The wiring is composed of, for example, a layered wiring provided on the main surface of the substrate portion 15 c and a via conductor that penetrates the insulating member 15.

  The vibration element 9 includes, for example, a flat plate-shaped piezoelectric element plate 10 (FIG. 2) and a pair of excitation electrodes 32 (see FIG. 4) provided on both main surfaces of the piezoelectric element plate 10. The piezoelectric element plate 10 is made of, for example, a quartz material such as quartz, cut at a predetermined angle with respect to a crystal axis, and has a rectangular shape in plan view. The vibration element 9 generates a thickness shear vibration at a predetermined frequency when a voltage is applied to the pair of excitation electrodes 32.

  The lid 13 is bonded to the upper surface of the first frame portion 15d and seals the first recess 15a. The lid 13 may be made of a conductive material such as metal, may be made of an insulating material, or may be made of a composite material in which an insulating layer and a conductive layer are stacked. For example, the lid 13 is made of a metal plate, and this metal plate is joined to the first frame portion 15d by seam welding or the like.

  For example, the thermostatic chamber 5 mounts the mounting base 17 on which the TCXO 3 is mounted, the case 19 that houses the TCXO 3, the heater 21 (FIG. 2) for heating the atmosphere in the case 19, and the OCXO 1 to an external device. A plurality of (in this embodiment, six) external terminals 23 (including 23W in FIG. 1) and various electronic components (not shown in FIGS. 1 and 2) mounted on the mounting substrate 17. Yes.

  The mounting substrate 17 is made of, for example, a printed wiring board, and includes an insulating substrate 24 and various conductors provided on the insulating substrate 24. The insulating base 24 is made of, for example, a glass epoxy material.

  The case 19 is made of, for example, a metal material, and houses the TCXO 3, the mounting substrate 17, and the heater 21. Although not particularly illustrated, the case 19 is configured, for example, by fixing a member constituting the lower surface of the case 19 and members constituting the upper surface and the outer peripheral surface of the case 19. It is preferable that the two members are hermetically joined by a sealing material or the like, and the inside of the case 19 is sealed.

  For example, the heater 21 is joined to a position overlapping the TCXO 3 on the lower surface of the mounting substrate 17. For example, the heater 21 is configured by sealing a conductor (resistor) extending in a predetermined pattern with an insulating material, and generates heat corresponding to a voltage applied via the mounting substrate 17.

  The plurality of external terminals 23 are, for example, pin-shaped terminals, and one end side is inserted into a hole formed in the mounting base 17 and is fixed to the mounting base 17 with solder or the like and electrically connected thereto. The other end sides of the plurality of external terminals 23 extend from, for example, the lower surface of the case 19. The plurality of external terminals 23 are fixed to the case 19 and may contribute to fixing the mounting base 17 and the case 19 while securing a space between the mounting base 17 and the lower surface of the case 19. .

  FIG. 3A is a bottom view of the TCXO 3, and FIG. 3B is a top view of the mounting substrate 17.

  As described above, the TCXO 3 has a plurality (six in FIG. 3) of first terminals 25 (including 25 W) for mounting the TCXO 3 on the mounting substrate 17 on the lower surface of the second frame portion 15 e. . The multiple first terminals 25 are, for example, layered. The arrangement positions of the plurality of first terminals 25 may be set as appropriate. For example, they are the four corners and the center of the long side of the second frame portion 15e.

  The mounting substrate 17 has a plurality (six in FIG. 3) of second terminals 27 (including 27 W) connected to the plurality of first terminals 25 on the upper main surface. The plurality of second terminals 27 are, for example, layered and connected to the plurality of first terminals 25 by bumps. Thereby, the TCXO 3 is fixed and electrically connected to the mounting substrate 17. The number of the plurality of second terminals 27 is the same as the number of the plurality of first terminals 25, for example.

  Further, the mounting substrate 17 includes a plurality of holes 24h through which the plurality of external terminals 23 are inserted, a plurality of third terminals 29 (including 29W) located on and / or around the inner peripheral surface of the plurality of holes 24h, A plurality of connection wirings 31 connecting the plurality of second terminals 27 and the plurality of third terminals 29 are provided. The plurality of third terminals 29 and connection wirings 31 are formed in layers on the surface of the insulating base 24, for example. The connection wiring 31 may be provided on the main surface below the mounting substrate 17 or inside the mounting substrate 17. The number of the plurality of third terminals 29 is the same as the number of the plurality of external terminals 23, for example.

  The plurality of external terminals 23 are inserted into the plurality of holes 24h, for example, and are fixed and connected to the plurality of third terminals 29 by a conductive material such as solder. Thereby, the plurality of first terminals 25 of the TCXO 3 are connected to the plurality of external terminals 23 via the plurality of second terminals 27 and the plurality of third terminals 29 of the mounting substrate 17.

  FIG. 4 is a block diagram showing a schematic configuration of the signal processing system of OCXO1.

  As described above, the OCXO 1 includes the TCXO 3 and the thermostat 5, and both are electrically connected by connecting a plurality of first terminals 25 and a plurality of second terminals 27. ing. In addition, various signals are input to the plurality of first terminals 25 of the TCXO 3 via the plurality of external terminals 23 of the thermostat 5 or various signals are output.

  The signals given to the plurality of external terminals 23 (first terminals 25) are, for example, for controlling the frequency of the oscillation signal generated by the power supply voltage Vcc, the reference potential GND, and the TCXO3 for driving the TCXO3 and the constant temperature bath 5. Are write signals Vw for writing information related to temperature compensation to the control voltages Vcon and TCXO3. The signal output from the plurality of external terminals 23 is, for example, the oscillation signal Vout generated by the TCXO 3.

  It should be noted that which role is assigned to the external terminal 23 at which position may be appropriately set. The same applies to the first terminal 25, the second terminal 27, and the third terminal 29. Hereinafter, for the sake of convenience, it is assumed that terminals with an additional sign of W are terminals to which the write signal Vw is input, and these terminals are the first write terminal 25W, the second write terminal 27W, and the third write terminal 29W. In some cases, the external write terminal 23W.

  As described above, the TCXO 3 includes the vibration element 9 and the IC 11 connected to the vibration element 9. The IC 11 includes, for example, an oscillation circuit 33 that generates a oscillation signal by applying a voltage to the vibration element 9, a temperature compensation circuit 35 that compensates for a temperature change of the oscillation signal, and a temperature compensation held by the temperature compensation circuit 35. And a rewriting circuit 37 for rewriting the contents of the data. The configurations of the oscillation circuit 33, the temperature compensation circuit 35, and the rewrite circuit 37 may be the same as known configurations.

  For example, the oscillation circuit 33 is not particularly shown, but an inverter whose input side and output side are connected to the vibration element 9, a feedback resistor connected to the input side and output side of the inverter, and between the input side of the inverter and the ground portion And a variable capacitance element arranged between the output side of the inverter and the ground portion.

  For example, the temperature compensation circuit 35 includes a variable capacitance element 39 disposed between the vibration element 9 and the ground portion, a compensation signal generation circuit 41 connected to the variable capacitance element 39, and a compensation signal generation circuit 41. A ROM 43, a RAM 45, and a first temperature sensor 47 are connected.

  Note that the variable capacitance element 39 of the temperature compensation circuit 35 may also be used as a variable capacitance element included in the oscillation circuit 33 in order to change the frequency of the oscillation signal in accordance with the control voltage Vcon. Further, the ROM 43 and the RAM 45 may be used also as a ROM and a RAM that hold information used by the oscillation circuit 33. The first temperature sensor 47 may be provided separately from the IC 11.

  The compensation signal generation circuit 41 applies a voltage corresponding to the temperature detected by the first temperature sensor 47 to the variable capacitance element 39 based on information stored in the ROM 43 or RAM 45. Thereby, the load capacity of the vibration element 9 changes according to the temperature, and the frequency of the oscillation signal is temperature-compensated.

  More specifically, for example, the change amount of the frequency of the oscillation signal that is not subjected to temperature compensation with respect to the temperature change is represented by a cubic function. The voltage to be applied to the variable capacitance element 39 in order to cancel out this change amount is also expressed by a cubic function with the temperature as a variable. The ROM 43 or the RAM 45 holds a coefficient of a cubic function and a constant value of this voltage. The compensation signal generation circuit 41 substitutes the temperature detected by the first temperature sensor 47 into a cubic function defined by the coefficient and constant value stored in the ROM 43 or the RAM 45 and applies it to the variable capacitance element 39. A power voltage is calculated and generated and applied to the variable capacitance element 39.

  For example, the rewriting circuit 37 rewrites (writes) the coefficient and constant value of the cubic function stored in the ROM 43 or the RAM 45.

  In addition to the heater 21 described above, the thermostat 5 controls the heater 21 based on, for example, a second temperature sensor 49 that detects the temperature at an appropriate position in the case 19 and the temperature detected by the second temperature sensor 49. And a temperature control circuit 51. For example, the temperature control circuit 51 feedback-controls the heater 21 so that the temperature detected by the second temperature sensor 49 is maintained at a preset temperature.

  Some TCXOs can output the temperature detected by the first temperature sensor 47 from the first terminal 25. When such TCXO is selected as TCXO 3, the heater 21 may be controlled based on the temperature detected by the first temperature sensor 47 without providing the second temperature sensor 49.

  The plurality of external terminals 23 exposed from the thermostat 5 and the plurality of first terminals 25 of the TCXO 3 are directly connected via the connection wiring 31 of the mounting substrate 17 as shown in FIG. . However, an appropriate circuit or electronic element may be interposed between the plurality of external terminals 23 and the plurality of first terminals 25. For example, an amplifier or an element for impedance matching may be interposed.

  FIG. 5 is a flowchart showing the procedure of the manufacturing method of OCXO1.

  In step ST1, TCXO3 is prepared. The ROM 43 of the TCXO 3 stores, for example, values of parameters (coefficients and constants of a cubic function) that define the temperature compensation amount. The value of this parameter is set based on, for example, the temperature characteristic of the frequency measured for each TCXO 3 and is written in the ROM 43 via the first write terminal 25W.

  Therefore, the deviation amount between the frequency of the oscillation signal output from the TCXO 3 and the frequency of the oscillation signal to be output from the TCXO 3 is within a predetermined allowable error range in a predetermined temperature atmosphere. In addition, the parameter values held in the TCXO 3 take into account the effects of manufacturing variations in the same type of product.

  In step ST2, the TCXO 3 is mounted on the mounting substrate 17. For example, the plurality of first terminals 25 of the TCXO 3 and the plurality of second terminals 27 of the mounting substrate 17 are fixed and connected by bumps (not shown) made of solder. The plurality of external terminals 23 are fixed to the mounting substrate 17 before or after the TCXO 3 is mounted on the mounting substrate 17.

  In step ST3, the TCXO 3 is accommodated in the case 19 while the plurality of external terminals 23 are exposed. For example, members constituting the case 19 are fixed to each other with an adhesive or the like so that the TCXO 3 is accommodated.

  In step ST4, the temperature characteristic of OCXO1 is measured. Specifically, the amount of deviation between the frequency of the oscillation signal to be output from the OCXO 1 and the frequency of the oscillation signal actually output from the OCXO 1 is measured.

  For example, as in the case of using the OCXO1, the power supply voltage Vcc, the reference potential GND, and the control voltage Vcon are applied to the plurality of external terminals 23 of the OCXO1, and the oscillation signal Vout subjected to temperature compensation by the TCXO3 is output from the external terminal 23 Let The thermostat 5 is driven by the supply of the power supply voltage Vcc and the reference potential GND, and the inside of the case 19 is maintained at a predetermined temperature.

  Then, for example, when the temperature of the thermostatic chamber 5 is sufficiently stabilized, for example, when a predetermined time elapses, the frequency of the oscillation signal that is actually output from the external terminal 23 of the OCXO 1 is measured. The amount of deviation from the frequency of the oscillation signal to be output from the external terminal 23 by the OCXO 1 is calculated.

  In the present embodiment, since the parameter value defining the temperature compensation amount is adjusted in the preparation of the TCXO 3 in step ST1, the portion of the deviation amount at this time exceeding the deviation amount allowed in step ST1 This is because the TCXO 3 is mounted on the mounting substrate 17.

  In step ST5, the parameter value defining the temperature compensation amount held in the ROM 43 of the OCXO1 is rewritten based on the deviation amount measured in step ST4.

  For example, the temperature characteristics after mounting are shifted by a predetermined shift amount (temperature deviation amount) along the temperature axis direction without changing the shape of the cubic curve (cubic function) representing the temperature characteristics before mounting. It is thought that it can be expressed approximately by what has been done. Therefore, it is only necessary to shift the cubic function of the voltage applied by the compensation signal generation circuit 41 along the temperature axis direction by the same shift amount as that described above.

  More specifically, for example, the following may be performed.

First, the value of the parameter that defines the temperature compensation amount stored in the ROM 43 is read via the external write terminal 23W. For example, the ROM 43 stores values of α, β, γ, and T _{0 in} the following equation (1). Equation (1) is an example of a cubic function of the voltage ΔV applied to the variable capacitance element 39 corresponding to the detected temperature T of the first temperature sensor 47.
ΔV = α (T−T ₀ ) ³ + β (T−T ₀ ) + γ (1)

Next, the read α, β, and γ values are written into the RAM 45, and the read T ₀ value slightly changed (increased or decreased) is written into the RAM 45 as a T ₀ value. Next, the compensation signal generation circuit 41 generates a voltage ΔV based on the values of α, β, γ, and T ₀ written in the RAM 45. Then, the amount of deviation between the frequency of the oscillation signal whose temperature has been compensated by the voltage ΔV and the frequency of the oscillation signal to be output by the OCXO 1 is measured.

Further, the operation of measuring the deviation amount by slightly changing the value of T ₀ held in the RAM 45 is repeated. Thereby, it is possible to search for a value of T ₀ where the deviation amount is within a predetermined allowable error range (for example, within the same range as the allowable error range of TCXO3) or the deviation amount is minimum. Then, the value of T ₀ held in the ROM 43 is rewritten to the optimum value of T ₀ searched.

  As can be understood from the above description, step ST4 and step ST5 may actually be performed inseparably and repeatedly.

  FIG. 6 is a flowchart showing a procedure of a modified example of the manufacturing method of OCXO1.

  This modification mainly differs from the procedure shown in FIG. 5 in the timing of temperature characteristic measurement and data writing.

  Specifically, first, similarly to steps ST1 and ST2 of FIG. 5, TCXO3 is prepared (step ST11), and TCXO3 is mounted on the mounting substrate 17 (step ST12).

  Next, the power supply voltage Vcc, the reference potential GND, and the control voltage Vcon are applied to the plurality of third terminals 29 of the mounting substrate 17, and the oscillation signal Vout subjected to temperature compensation by the TCXO 3 is acquired from the third terminal 29. The frequency is measured (step ST13).

  Next, based on this measurement result, a write signal Vw is input to the third write terminal 29W, and the parameter value defining the temperature compensation amount held in the ROM 43 is rewritten (step ST14).

  Thereafter, TCXO3 is accommodated in case 19 in the same manner as in step ST3 of FIG. 5 (step ST15).

  As described above, in the modified example of FIG. 6, after the TCXO 3 is mounted on the mounting substrate 17 and before the TCXO 3 is accommodated in the case 19, the parameter value defining the temperature compensation amount held by the ROM 43 is optimized and rewritten. .

  In steps ST13 and ST14, the mounting substrate 17 and the TCXO3 are accommodated, for example, in a thermostat prepared for measurement. The temperature in this thermostat is maintained at a temperature equivalent to the temperature that the thermostat 5 should maintain, for example. In this case, optimization of parameter values in steps ST13 and ST14 may be performed in the same manner as in steps ST3 and ST4 in FIG.

  Further, in steps ST13 and ST14, by changing the temperature in the thermostat chamber for measurement in various ways, the change of the frequency of the oscillation signal with respect to the temperature change (temperature characteristic itself) is the same as the parameter optimization in the TCXO3 before mounting. ) May be measured to optimize the parameters. In this case, even if the TCXO 3 prepared in step ST11 holds a parameter value that does not take into account the influence of individual variations (a parameter value commonly set for the same type of TCXO). It may be good, or even such a value may not be held.

  In this modification, since the write signal Vw is input to the third write terminal 29W, the external write terminal 23W is not necessary. Therefore, in the case of adopting this modification, the external write terminal 23W may be omitted.

  The plurality of external terminals 23 may be fixed to the mounting base 17 before step ST14, or may be fixed to the mounting base 17 after step ST14. When the plurality of external terminals 23 are fixed to the mounting substrate 17 before step ST14, the input of the power supply voltage Vcc, the reference potential GND, the control voltage Vcon, and the like and the oscillation signal Vout in step ST14 are acquired by a plurality of external terminals. It may be made for the terminal 23.

  As described above, the OCXO 1 of the present embodiment includes the TCXO 3 having the plurality of first terminals 25, the plurality of first terminals 25 connected to the plurality of first terminals 25 via the plurality of second terminals 27 and the plurality of connection wirings 31. It has a mounting substrate 17 having three terminals 29, a case 19 that houses TCXO 3, and a heater 21 that can heat the atmosphere in the case 19. The plurality of first terminals 25 include a first write terminal 25W that can write information defining a temperature compensation amount in the ROM 43 of the TCXO3. The multiple third terminals 29 include a third write terminal 29W connected to the second write terminal 27W.

  Therefore, as described with reference to FIG. 6, it is possible to optimize the information defining the temperature compensation amount using the plurality of third terminals 29 in a state where the TCXO 3 is mounted on the mounting substrate 17. As a result, it is possible to perform temperature compensation in consideration of the effect of mounting. The first write terminal 25 </ b> W may be provided on the side surface of the element mounting member 7 separately from the other first terminals 25. In this case, it is not impossible to rewrite the ROM 43 or RAM 45 without using the third write terminal 29W in a state where the TCXO 3 is mounted on the mounting substrate 17. However, in general, in the mounting substrate 17 on which the TCXO 3 is mounted, the third terminal 29 is in a position where a probe or the like can be brought into contact more easily than the first terminal 25 and has a large area. Therefore, by providing the third write terminal 29W, rewriting of the ROM 43 or RAM 45 after mounting is facilitated. Further, by providing the third write terminal 29W, it is possible to provide the external write terminal 23W.

  In the present embodiment, the OCXO 1 further includes a plurality of external terminals 23 that are connected to the plurality of third terminals 29 and are exposed to the outside of the case 19, and the plurality of external terminals 23 are connected to the third write terminals 29W. A connected external write terminal 23W is included.

  Therefore, as described with reference to FIG. 5, the information for defining the temperature compensation amount using the plurality of external terminals 23 in the state where the TCXO 3 mounted on the mounting substrate 17 is accommodated in the case 19 is optimized. be able to. As a result, it is possible to perform temperature compensation in consideration of the effect of mounting. Further, the influence of the case 19 is taken into consideration, and it is expected that the temperature compensation is further suitably performed.

  In the present embodiment, the TCXO 3 includes the piezoelectric substrate 10, the IC 11 including the first temperature sensor 47 used for temperature compensation, the first recess 15 a that houses the piezoelectric substrate 10, and the first recess 15 a. And an element mounting member 7 which is located on the back surface and has a second recess 15b for accommodating the IC 11.

  Therefore, the distance between the piezoelectric element 10 and the first temperature sensor 47 is short, and the response of the detection value of the first temperature sensor 47 to the temperature change of the piezoelectric element 10 is high. As a result, the starting characteristics are improved. As a result, information that defines the optimized temperature compensation amount is effectively used.

  In another aspect, in the manufacturing method of the OCXO 1 of the present embodiment, the TCXO 3 having the plurality of first terminals 25 is connected to the plurality of first terminals 25 via the plurality of second terminals 27 and the plurality of connection wirings 31. The mounting step (step ST2 or ST12) for mounting on the mounting base 17 having a plurality of third terminals 29 and the temperature characteristics of the TCXO 3 mounted on the mounting base 17 are measured via any one of the plurality of third terminals 29. A measurement process (step ST4 or ST13) to be performed, and a writing process (step 3) in which information (a coefficient of a cubic function and / or a constant value) defining the temperature compensation amount is written in the ROM 43 of the TCXO 3 based on the measurement result of the measurement process. ST5 or ST14).

  Therefore, as described in the effect exhibited by the configuration of the OCXO 1 of the present embodiment, temperature compensation that takes into account the influence of mounting becomes possible. Further, when information is written through any one of the plurality of third terminals 29 (third write terminal 29W), rewriting of information in consideration of mounting is facilitated.

  In the present embodiment, the OCXO 1 manufacturing method exposes the plurality of external terminals 23 connected to the plurality of third terminals 29 after the mounting process (step ST2) and before the measurement process (step ST4). However, it further includes an accommodating step (step ST3) for accommodating the TCXO3 in the case 19. In the measurement process, the temperature characteristics of the TCXO 3 accommodated in the case 19 are measured via any of the plurality of external terminals 23. In the writing process (step ST5), information defining the temperature compensation amount is written in the ROM 43 via one of the other external terminals 23 (external write terminal 23W).

  Therefore, as described in the effect produced by the configuration of the OCXO 1 of the present embodiment, the influence of the case 19 is also taken into consideration, and it is expected that the temperature compensation is further suitably performed.

  In the above embodiment, OCXO1 is an example of a thermostatic chamber-equipped piezoelectric device, TCXO3 is an example of a temperature-compensated piezoelectric device, heater 21 is an example of a temperature adjustment element, and ROM 43 is an example of a memory. The piezoelectric element plate 10 is an example of a piezoelectric body, the first temperature sensor 47 is an example of a temperature sensor, and the IC 11 is an example of an integrated circuit element.

  The present invention is not limited to the above embodiment, and may be implemented in various aspects.

  For example, the piezoelectric device is not limited to an oscillator. For example, a filter such as a SAW filter may be used. In the case of a filter, for example, the value of a parameter that defines the amount of temperature compensation is optimized so that the waveform of an output signal when an input signal having a predetermined waveform is filtered approaches a predetermined shape.

  The oscillator may input and output signals other than those exemplified in the embodiment. For example, the oscillator may be one that does not receive a control voltage (outputs an oscillation signal having a predetermined constant frequency), or one that receives an enable / disable signal. Alternatively, two oscillation signals having different frequencies or the same frequency may be output.

  The vibration element is not limited to one in which a pair of electrodes is provided on both main surfaces of the piezoelectric body, and a pair of electrodes is provided on one main surface of the piezoelectric body like a SAW type vibration element. Also good. The cut angle of the piezoelectric body may be set as appropriate. The piezoelectric body is not limited to quartz but may be ceramic, for example.

  The element mounting member on which the piezoelectric body (vibration element) and the integrated circuit element are mounted is not limited to a so-called H-type having two concave portions on opposite sides. For example, the piezoelectric body and the integrated circuit element may be accommodated in one recess.

  The temperature-compensated piezoelectric device (TCXO or the like) is not limited to those mounted on the mounting substrate by bumps, and may be mounted on the mounting substrate by bonding wires or pin-shaped first terminals, for example.

  The case is not limited to a case that accommodates a mounting substrate in addition to a temperature-compensated piezoelectric device (such as TCXO). For example, only the surface of the mounting substrate on which the TCXO is mounted may be covered. In other words, the mounting substrate may constitute the bottom of the thermostat.

  In this case, the third terminal of the mounting substrate may be used as an external terminal exposed to the outside of the case. In the case where the third terminal is used as an external terminal, after the temperature-compensated piezoelectric device is accommodated in the case, signals are input / output to / from the third terminal, and information relating to temperature characteristic measurement and temperature compensation May be written.

  The temperature adjusting element is not limited to the element that performs heating (heater), and may be an element that performs cooling. For example, a Peltier element exposed inside and outside the case may be provided and function as a heating element, a cooling element, or a heating / cooling element capable of both heating and cooling. The temperature adjustment element does not necessarily have to be accommodated in the case, and may be disposed outside the case and may heat or cool the atmosphere inside the case by heating or cooling the case.

The information defining the temperature compensation amount is not limited to the coefficient and constant value of the cubic function. For example, the temperature compensation amount of the oscillator can be defined by dividing a predetermined temperature range into a plurality of divisions and by a linear function or a quadratic function for each division. The value of the coefficient or constant of the quadratic function is information that defines the temperature compensation amount. Also, without changing the coefficient and constant values of the function, information on the temperature deviation itself (for example, the difference between the initial value of T ₀ and the optimum value in the embodiment) is held as information, and the detected temperature is substituted into the function. In this case, the amount of deviation may be added from the detected temperature as a variable.

In embodiments, the values of T ₀ is output oscillation signal to TCXO3 while changing little by little, it has been probed optimization of values of T _0, even if optimization of the values of T ₀ is determined by the calculation Good. For example, in the equation obtained by substituting the values of α, β, γ, T, T ₀ (initial value), Δf, and F into the following equation (2), the value of ΔT is obtained by calculation, and T ₀ + ΔT good a value as a new value of T _0.
α (T−T ₀ ) ³ + β (T−T ₀ ) + γ + Δf / F
= Α (T− (T ₀ + ΔT)) ³ + β (T− (T ₀ + ΔT)) + γ (2)
However, Δf is the amount of frequency shift measured in step ST4, and F is a proportionality constant when it is assumed that the voltage applied to the variable capacitance element 39 and the amount of change in the frequency of the oscillation signal have a linear relationship.

  In the invention of the manufacturing method, the second write terminal, the third write terminal, and the external write terminal may not be provided. For example, as described above, in the TCXO in which the first input / output terminal is provided on the bottom surface while the first write terminal is provided on the side surface, after the TCXO is mounted on the mounting base, It is possible to input a write signal to the first write terminal while inputting / outputting a signal to / from the TCXO through the third terminal.

  DESCRIPTION OF SYMBOLS 1 ... Crystal oscillator with a thermostat (OCXO, piezoelectric device with a thermostat), 3 ... Temperature compensated crystal oscillator (TCXO, temperature compensated piezoelectric device), 17 ... Mounting substrate, 19 ... Case, 21 ... Heater (temperature adjustment element) ), 23 ... external terminal, 23W ... external write terminal, 25 ... first terminal, 25W ... first write terminal, 27 ... second terminal, 27W ... second write terminal, 29 ... third terminal, 29W ... third write Terminals 34... ROM (memory).

Claims (6)

A temperature compensated piezoelectric device having a plurality of first terminals;
A plurality of second terminals connected to the plurality of first terminals; a plurality of connection wires extending from the plurality of second terminals; and a plurality of second terminals connected to the plurality of second terminals by the plurality of connection wires. A mounting substrate having three terminals;
A case housing the temperature-compensated piezoelectric device;
A temperature adjusting element capable of performing at least one of heating and cooling of the atmosphere in the case;
Have
The plurality of first terminals include a first write terminal capable of writing information defining a temperature compensation amount in a memory of the temperature compensated piezoelectric device,
The plurality of third terminals include a third writing terminal connected to the first writing terminal. A plurality of external terminals connected to the plurality of third terminals and exposed to the outside of the case;
The thermostatic chamber-equipped piezoelectric device according to claim 1, wherein the plurality of external terminals include an external write terminal connected to the third write terminal. The temperature compensated piezoelectric device is:
A piezoelectric body;
An integrated circuit element including a temperature sensor used for temperature compensation;
The constant temperature according to claim 1, further comprising: an element mounting member having a first concave portion that accommodates the piezoelectric body and a second concave portion that is located on a back surface of the first concave portion and accommodates the integrated circuit element. Piezoelectric device with tank. A temperature-compensated piezoelectric device having a plurality of first terminals, a plurality of second terminals connected to the plurality of first terminals, a plurality of connection wirings extending from the plurality of second terminals, and the plurality of connection wirings Mounting on a mounting substrate having a plurality of third terminals connected to the plurality of second terminals by:
A measurement step of measuring the temperature characteristics of the temperature compensated piezoelectric device mounted on the mounting substrate via any of the plurality of third terminals;
Based on the measurement result of the measurement step, a writing step of writing information that defines a temperature compensation amount in the memory of the temperature compensated piezoelectric device;
The manufacturing method of the piezoelectric device with a thermostat which has this. The method for manufacturing a piezoelectric device with a thermostatic chamber according to claim 4, wherein in the writing step, the information is written into the memory via any one of the plurality of third terminals. After the mounting step and before the measuring step, the method further includes a housing step of housing the temperature compensated piezoelectric device in a case while exposing a plurality of external terminals connected to the plurality of third terminals,
In the measurement step, the temperature characteristics of the temperature compensated piezoelectric device housed in the case are measured via any of the plurality of external terminals,
The method for manufacturing a piezoelectric device with a thermostatic chamber according to claim 5, wherein, in the writing step, the information is written into the memory via any one of the plurality of external terminals.

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