A thermally sensitive crystal resonator using a quartz crystal as a feedback medium and a method thereof

Abstract

The present invention relates to a thermistor crystal resonator and a method thereof using a quartz wafer as a feedback medium. Two quartz wafers are installed in a single ceramic base. A frequency performance quartz wafer and a temperature feedback quartz wafer are fixed on a glue dispensing platform on the right side of the ceramic base through conductive glue dots, and are respectively connected to the back of the ceramic base. The frequency performance quartz wafer is used to provide the operating frequency of the thermistor crystal resonator. The temperature feedback quartz wafer indirectly provides a temperature feedback signal to the outside through the change of its own frequency with temperature. The external circuit adjusts the load of the thermistor crystal resonator according to the temperature feedback signal provided by the temperature feedback quartz wafer and the inherent temperature-frequency characteristics of the frequency performance quartz wafer, thereby achieving a compensation effect on the frequency of the frequency performance quartz wafer. Advantages: The temperature feedback quartz wafer is used instead of the thermistor to feedback the temperature signal, and the conductive glue is used for curing and conducting, thereby improving the authenticity and accuracy of the temperature feedback signal and improving the reliability of the product.

Description

Technical Field

[0001] The invention discloses a thermal-sensitive crystal resonator using a quartz crystal chip as a feedback medium, and belongs to the technical field of manufacturing quartz electronic components. Background Art

[0002] Quartz crystal components provide clock signals for various circuit systems and are also called the "heart" of electronic systems. Due to the inherent temperature characteristics of the quartz wafer, the frequency of ordinary quartz crystal resonators will have a large deviation as the temperature changes. Thermistor crystal resonators add temperature feedback to ordinary quartz crystal resonators, and cooperate with external circuits to compensate for the frequency deviation of the resonator as the temperature changes, so that the frequency of thermistor crystal resonators within the operating temperature range is kept within a small frequency deviation range.

[0003] Thermistors in the current market use thermistors as feedback media, and indirectly feedback changes in the resonator's operating temperature based on changes in thermistor resistance. The thermistor is fixed in a groove on the back of the base by solder paste. Due to the different materials and cavities of the thermistor and the quartz wafer, there is a certain deviation in the actual operating temperature of the thermistor and the quartz wafer. Moreover, when the thermistor is soldered on the PCB board, the solder paste that fixes the thermistor is prone to melt again due to the temperature rising again, resulting in serious defects such as thermistor desoldering or cold soldering, which ultimately causes the thermistor to fail.

[0004] When voltage is applied to both ends of a quartz crystal, the crystal deforms, and the strain is proportional to the field strength, converting electrical energy into mechanical energy. This phenomenon is called the inverse piezoelectric effect of quartz. The inverse piezoelectric effect can be used not only to make quartz crystal frequency components, but also to make temperature sensors. Quartz crystal temperature sensors have the characteristics of large temperature coefficient, short thermal response time, good linearity, and high frequency stability. The inherent temperature-frequency curve of LC-cut quartz crystal is approximately a linear curve, and its linearity is ±0.02℃. Summary of the invention

[0005] The present invention proposes a thermistor crystal resonator with a quartz wafer as a feedback medium. The purpose is to solve the problem of slow thermal response and distortion caused by thermistors due to material and space reasons, and the problem of desoldering or cold soldering caused by the reversibility of the curing of solder paste. A "one"-shaped double-chip structure is proposed, and a temperature feedback quartz wafer is used to replace the thermistor for temperature signal feedback, and conductive glue is used for curing and conduction, so as to improve the authenticity and accuracy of the temperature feedback signal and improve the reliability of the product.

[0006] The technical solution of the present invention is: a thermistor crystal resonator with a quartz wafer as a feedback medium, which uses the quartz wafer as a feedback medium to indirectly provide a temperature feedback signal, thereby realizing frequency compensation of the thermistor crystal resonator by an external circuit. Its structure includes a ceramic base 1, a frequency performance quartz wafer 3, a temperature feedback quartz wafer 4, and a cover plate 5. The frequency performance quartz wafer 3 and the temperature feedback quartz wafer 4 are fixed and conductive to the ceramic base 1 through a conductive glue 2, and the ceramic base 1 is sealed and connected to the cover plate 5.

[0007] The ceramic base 1 is an "I"-shaped structure, with four dispensing stations in the cavity, two dispensing stations on each side, clockwise are 1# dispensing station 6, 2# dispensing station 7, 3# dispensing station 8, 4# dispensing station 9, and 6 pins are arranged on the back, clockwise are 1# pin, 2# pin, 3# pin, 4# pin, 5# pin, 6# pin, 1# dispensing station 6 and 2# dispensing station 7 are respectively connected to 1# pin and 4# pin, 3# dispensing station 8 and 4# dispensing station 9 are respectively connected to 2# pin and 5# pin, and their heights are higher than 1# dispensing station 6 and 2# dispensing station 7.

[0008] The frequency performance quartz crystal 3 is of AT-cut type, and its temperature-frequency characteristic curve is approximately a cubic curve.

[0009] The temperature feedback quartz crystal 4 is of LC cut type, and its temperature-frequency characteristic curve is approximately a linear curve.

[0010] The main material of the electrode plating of the frequency performance quartz wafer 3 and the temperature feedback quartz wafer 4 is gold.

[0011] The ceramic base 1 and the cover plate 5 are vacuum sealed to ensure a vacuum environment in the sealed cavity.

[0012] The working method is characterized by comprising the following steps:

[0013] 1) Use conductive glue dots to fix the frequency performance quartz wafer 3 with the plated electrodes to the 1# glue dispensing station 6 and the 2# glue dispensing station 7 and connect them to the 1# pin and the 4# pin on the back of the base respectively. After the conductive glue is cured, use the ion etching fine-tuning technology to fine-tune the frequency of the frequency performance quartz wafer 3;

[0014] 2) Use conductive glue dots to fix the temperature feedback quartz chip 4 with the plated electrodes to the 3# glue dispensing station 8 and the 4# glue dispensing station 9 and connect them to the 2# pin and the 5# pin on the back of the base respectively. After the conductive glue is cured, use the ion etching fine-tuning technology to fine-tune the frequency of the temperature feedback quartz chip 4;

[0015] 3) The ceramic base 1 and the cover plate 5 are vacuum-sealed by using vacuum sealing technology to ensure a vacuum environment in the sealed cavity.

[0016] Beneficial effects of the present invention: A thermistor crystal resonator with a quartz wafer as a feedback medium uses a quartz wafer to replace a thermistor for temperature signal feedback, and replaces a two-cavity "H" type structure with a single-cavity "I" type structure in structure. The temperature feedback quartz wafer and the frequency performance quartz wafer are made of the same material and are in the same cavity. The temperature changes of the two are closer than the temperature changes of thermistors and frequency performance quartz wafers with different materials and in different cavities. At the same time, the linear deviation of the frequency temperature curve of the temperature feedback quartz wafer can reach 0.002%, which generally improves the authenticity and accuracy of the temperature feedback signal; in addition, when the solder paste that fixes the thermistor is soldered on the PCB board, it is easy to melt again due to the temperature rising again, resulting in serious defects such as the thermistor desoldering or cold soldering, and finally causing the thermistor to fail. The irreversibility of the temperature feedback quartz wafer solidified by the conductive adhesive can avoid the occurrence of this problem, thereby improving the reliability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 Schematic diagram of a thermistor crystal structure using a quartz crystal as feedback medium.

[0018] Attached Figure 2 It is a schematic diagram of the traditional thermistor crystal structure using thermistor as feedback medium.

[0019] Attached Figure 3 It is a front perspective schematic diagram of the ceramic base 1.

[0020] Attached Figure 4 It is a three-dimensional schematic diagram of the back side of the ceramic base 1.

[0021] Attached Figure 5 It is a schematic diagram of the KV ring layer circuit of the ceramic base 1.

[0022] Attached Figure 6 It is a schematic diagram of the circuits of the 8th and 9th layers of the dispensing station of the ceramic base 1.

[0023] Attached Figure 7 This is a schematic diagram of the circuits of the 6th and 7th layers of the dispensing station of the ceramic base 1.

[0024] Attached Figure 8 This is a schematic diagram of the dispensing stations 6, 7 and the 1#, 4# conductive wiring layer circuits of the ceramic base 1.

[0025] Attached Fig. 9 This is a schematic diagram of the circuits of the dispensing stations 8, 9 and the 5# and 2# conductive routing layers of the ceramic base 1.

[0026] Attached Fig.10 It is a schematic diagram of the PIN foot layer of the ceramic base 1.

[0027] In the figure, 1 is the ceramic base, 2 is the conductive glue dot, 3 is the frequency performance quartz chip, 4 is the temperature feedback quartz chip, 5 is the cover plate, 6-9 are the glue dispensing station, and 1#-1# are the PIN pins. DETAILED DESCRIPTION

[0028] A thermistor crystal resonator with a quartz wafer as a feedback medium, a single ceramic base 1 contains two quartz wafers, wherein a frequency performance quartz wafer 3 is fixed on the dispensing platform on the left side of the ceramic base through a conductive glue dot 2, and is respectively connected to the 1# and 4# phases on the back of the ceramic base; a temperature feedback quartz wafer 4 is fixed on the dispensing platform on the right side of the ceramic base through a conductive glue dot 2, and is respectively connected to the 2# and 5# phases on the back of the ceramic base. The frequency performance quartz wafer 3 is used to provide the working frequency of the thermistor crystal resonator, and the temperature feedback quartz wafer 4 indirectly provides a temperature feedback signal to the outside through the change of its own frequency with temperature. The external circuit adjusts the load of the thermistor crystal resonator according to the temperature feedback signal provided by the temperature feedback quartz wafer 4 and the inherent temperature-frequency characteristics of the frequency performance quartz wafer 3, thereby achieving a compensation effect on the frequency of the frequency performance quartz wafer 3, and ensuring that the frequency of the thermistor crystal resonator within the working temperature range is kept within a small frequency deviation range.

[0029] The technical solution of the present invention is further described below in conjunction with the accompanying drawings

[0030] As attached Figure 1-5 As shown, its structure includes a ceramic base 1, conductive glue dots 2, a frequency performance quartz chip 3, a temperature feedback quartz chip 4, and a cover plate 5. The ceramic base 1 is an "I"-shaped structure. There are two dispensing stations on the left and right sides of the single cavity. The dispensing stations 6 and 7 are respectively connected to the 1# and 3# pins on the back of the base, and the dispensing stations 8 and 9 are respectively connected to the 2# and 5# pins on the back of the base, and the height is higher than the dispensing stations 6 and 7.

[0031] As attached Figure 6-10 As shown, the AT-cut frequency performance quartz wafer 3 with the electrode plated is fixed to the dispensing stations 6 and 7 by using the conductive glue dots 2 and is respectively connected to the back sides 1# and 4# of the base. After the conductive glue is cured, the frequency performance quartz wafer 3 is fine-tuned by using the ion etching fine-tuning technology. After fine-tuning, the LC-cut temperature feedback quartz wafer 4 with the electrode plated is fixed to the dispensing stations 8 and 9 by using the conductive glue dots 2 and is respectively connected to the back sides 5# and 2# of the base. After the conductive glue is cured, the frequency of the temperature feedback quartz wafer 4 is fine-tuned by using the ion etching fine-tuning technology. After fine-tuning, the ceramic base 1 and the cover plate 5 are vacuum-sealed by using the vacuum sealing technology to ensure the vacuum environment in the sealed cavity.

Claims

1. A thermally sensitive crystal resonator using a quartz crystal as a feedback medium, characterized in that A quartz crystal chip is used as a feedback medium to indirectly provide a temperature feedback signal, thereby realizing frequency compensation of a thermistor crystal resonator by an external circuit. The structure comprises a ceramic base (1), a frequency performance quartz crystal chip (3), a temperature feedback quartz crystal chip (4), and a cover plate (5). The frequency performance quartz crystal chip (3) and the temperature feedback quartz crystal chip (4) are fixed and connected to the ceramic base (1) by means of a conductive adhesive (2), and the ceramic base (1) and the cover plate (5) are sealed and connected.

2. A thermistor crystal resonator with a quartz crystal as a feedback medium according to claim 1, characterized in that The ceramic base 1 is of an "I"-shaped structure, with four dispensing stations arranged in the cavity, two dispensing stations on each of the left and right sides, which are the 1# dispensing station (6), the 2# dispensing station (7), the 3# dispensing station (8), and the 4# dispensing station (9) in clockwise order, and six pins are arranged on the back, which are the 1# pin, the 2# pin, the 3# pin, the 4# pin, the 5# pin, and the 6# pin in clockwise order, and the 1# dispensing station (6) and the 2# dispensing station (7) are respectively connected to the 1# pin and the 4# pin, and the 3# dispensing station (8) and the 4# dispensing station (9) are respectively connected to the 2# pin and the 5# pin, and are higher than the 1# dispensing station (6) and the 2# dispensing station (7).

3. A thermistor crystal resonator with a quartz crystal as a feedback medium according to claim 1, characterized in that The frequency performance quartz wafer is AT-cut, and the temperature-frequency characteristic curve is a cubic curve.

4. A thermistor crystal resonator with a quartz crystal as a feedback medium according to claim 1, characterized in that The temperature feedback quartz crystal wafer is of LC cut type, and the temperature frequency characteristic curve is a linear curve.

5. A thermistor crystal resonator with a quartz crystal as a feedback medium according to claim 1, characterized in that The electrode coating material of the frequency performance quartz wafer and the temperature feedback quartz wafer is gold.

6. A thermally sensitive crystal resonator using a quartz crystal as a feedback medium according to claim 1, characterized in that The ceramic base and the cover plate are vacuum sealed to ensure a vacuum environment in the sealed cavity.

7. A method for operating a thermistor crystal resonator using a quartz crystal as a feedback medium according to any one of claims 1 to 6, characterized in that The steps include: 1) Use conductive glue dots to fix the frequency performance quartz wafer with plated electrodes to the 1# dispensing station and the 2# dispensing station and connect them to the 1# pin and the 4# pin on the back of the base respectively. After the conductive glue is cured, use the ion etching fine-tuning technology to fine-tune the frequency performance quartz wafer; 2) Use conductive glue dots to fix the temperature feedback quartz chip with the plated electrodes to the 3# glue dispensing station and the 4# glue dispensing station and connect them to the 2# pin and the 5# pin on the back of the base respectively. After the conductive glue is cured, use the ion etching fine-tuning technology to fine-tune the frequency of the temperature feedback quartz chip; 3) Use vacuum sealing technology to vacuum seal the ceramic base and the cover plate to ensure the vacuum environment in the sealed cavity; 4) The frequency performance quartz wafer provides the operating frequency of the thermistor crystal resonator. The temperature feedback quartz wafer indirectly provides a temperature feedback signal to the outside through the change of its own frequency with temperature. The external circuit adjusts the load of the thermistor crystal resonator according to the temperature feedback signal provided by the temperature feedback quartz wafer and the inherent temperature-frequency characteristics of the frequency performance quartz wafer, thereby compensating the frequency of the frequency performance quartz wafer to ensure that the frequency of the thermistor crystal resonator is maintained within a small frequency deviation range within the operating temperature range.

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