Structure of an integrated crystal oscillator package

Abstract

A structure of an integrated crystal oscillator package has a first quartz crystal resonator, a second quartz crystal resonator, and application-specific integrated circuit chip (ASIC) combined in a package. The ASIC has a switch control for receiving audio formats of 44.1 kHz and 48 kHz with different hi-fidelity (hi-fi). The first quartz crystal resonator has a first clock rate corresponding to the 44.1 kHz frequency and the second quartz crystal resonator has a second clock rate corresponding to the 48 kHz frequency to be switched by the present invention in operation.

Claims

1. A structure of an integrated crystal oscillator package, comprising: a substrate having a first depression arranged thereon and a second depression arranged at a bottom thereof, said first depression having a first stair surface with a first conductive section and a second stair surface with a second conductive section, and said second depression having a third conductive section; a first quartz crystal resonator having an end thereof fixed on the first conductive section; a second quartz crystal resonator having an end thereof fixed on the second conductive section; a cover disposed on the first depression for sealing the first and second quartz crystal resonators therein; and an application-specific integrated circuit chip (ASIC) coupled to the third conductive section, said third conductive section further separately connected to the first and second conductive sections; whereby the ASIC has a switch control to switch between audio formats with different degree of hi-fidelity (hi-fi) when receiving them and to operate correspondingly to a first clock rate output from the first quartz crystal resonator or to a second clock rate output from the second quartz crystal resonator.

2. The structure of an integrated crystal oscillator package as claimed in claim 1, wherein frequencies of 44.1 kHz and a multiple thereof are corresponding to the first clock rate, and frequencies of 48 kHz and a multiple thereof are corresponding to the second clock rate.

3. The structure of an integrated crystal oscillator package as claimed in claim 1, wherein the first and second quartz crystal resonators have either the same sides or opposite sides fixed on the first and second conductive sections.

4. The structure of an integrated crystal oscillator package as claimed in claim 1, wherein the substrate is a ceramic substrate or a PCB to have electric wires arranged therein separately connecting the third conductive section with the first and second conductive sections for the switch control to operate.

5. The structure of an integrated crystal oscillator package as claimed in claim 4, wherein the substrate further has a first bond pad group and a second bond pad group at a bottom thereof, said first and second bond pad groups individually coupled to the ASIC via the electric wires for the present invention to form a surface mount device (SMD).

6. The structure of an integrated crystal oscillator package as claimed in claim 1, wherein the switch control has a first switch and a second switch to switch between a first sampling frequency output and a second sampling frequency output and to simultaneously output both frequencies.

7. A structure of an integrated crystal oscillator package, comprising: a substrate having a first depression arranged thereon and a second depression arranged at a bottom thereof, said first depression having a first stair surface with a first conductive section and a second stair surface with a second conductive section, and said second depression having a third conductive section; a first quartz crystal resonator having an end thereof fixed on the first conductive section; a second quartz crystal resonator having an end thereof fixed on the second conductive section; a cover disposed on the first depression for sealing the first and second quartz crystal resonators therein; and an application-specific integrated circuit chip (ASIC) coupled to the third conductive section, said third conductive section further separately connected to the first and second conductive sections; whereby the ASIC has a switch control for operation when receiving audio format of 44.1 kHz and 48 kHz with different degree of hi-fidelity (hi-fi), the 44.1 kHz and a multiple thereof being corresponding to a first clock rate output from the first quartz crystal resonator and the 48 kHz and a multiple thereof being corresponding to a second clock rate output from the second quartz crystal resonator.

8. The structure of an integrated crystal oscillator package as claimed in claim 7, wherein the switch control has a first switch and a second switch to switch between a first sampling frequency output and a second sampling frequency output and to simultaneously output both frequencies.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1A is a schematic diagram illustrating a structure of a conventional crystal resonator;

(2) FIG. 1B is a schematic view of two conventional crystal resonators mounted on a PCB;

(3) FIG. 1C is a schematic diagram illustrating a structure of a conventional crystal oscillator;

(4) FIG. 1D is a schematic view of two conventional crystal oscillators mounted on a PCB;

(5) FIG. 1E is a schematic diagram illustrating a structure of another conventional crystal oscillator;

(6) FIG. 1F is a schematic view of two conventional crystal oscillators in FIG. 1E mounted on a PCB;

(7) FIG. 1G is a schematic view of a conventional codec;

(8) FIG. 1H is a schematic view of a conventional high-fidelity (hi-fi) system;

(9) FIG. 1I is a schematic view of a conventional hi-fi system with a package of two crystal resonators;

(10) FIG. 1J is a schematic diagram illustrating a structure of a downsized crystal resonator package according to the prior art;

(11) FIG. 1K is a schematic diagram showing the downsized crystal resonator package mounted on a PCB;

(12) FIG. 1L is a schematic diagram illustrating a structure of a downsized crystal resonator package with airtight sealing according to the prior art;

(13) FIG. 1M is a schematic diagram showing the downsized crystal resonator package with airtight sealing mounted on a PCB;

(14) FIG. 2 is a perspective view of the present invention;

(15) FIG. 3 is a sectional view along line 3-3 in FIG. 2;

(16) FIG. 4 is another sectional view of the present invention;

(17) FIG. 5 is a schematic diagram illustrating the present invention mounted on a PCB;

(18) FIG. 6A is a circuit diagram of the present invention; and

(19) FIG. 6B is an application example of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(20) Referring to FIGS. 2-6B, in a preferred embodiment, an integrated crystal oscillator package 60 comprises a substrate 70, a first quartz crystal resonator 80A, a second quartz crystal resonator 80B, a cover 75, and an application-specific integrated circuit chip (ASIC) 90.

(21) The substrate 70 includes a first depression 71 arranged thereon and a second depression 74 arranged at a bottom thereof. The first depression 71 further has a first stair surface 72 with a first conductive section 721 and a second stair surface 73 with a second conductive section 731; the second depression 74 further has a third conductive section 741 therein. In this embodiment, the substrate 70 is a ceramic substrate or a PCB to have electric wires (not shown) arranged therein, and the first, second, and third conductive sections 721, 731, 741 have a plurality of connecting points.

(22) The first quartz crystal resonator 80A has an end thereof fixed on the first conductive section 721 on the first stair surface 72, and the second quartz crystal resonator 80B has an end thereof fixed on the second conductive section 731 on the second stair surface 73. The cover 75 is disposed on the first depression 71 for sealing the first and second quartz crystal resonators 80A, 80B therein.

(23) Referring to FIGS. 3 and 4, in this embodiment, the first and second quartz crystal resonators 80A, 80B may have their fixed ends either on the same sides or at opposite sides. Furthermore, the first and second quartz crystal resonators 80A, 80B are respectively coupled to the first and second conductive sections 721, 731 via the connecting points thereof, and the substrate 70 and the cover 75 have the first and second quartz crystal resonators 80A, 80B airtight sealed therein.

(24) The ASIC 90 is coupled to the third conductive section 741 which is further separately connected to the first and second conductive sections 721, 731. In this embodiment, the ASIC 90 is coupled to the connecting points of the third conductive section 741 and has the electric wires arranged therein to connect the third conductive section 741 with the first and second conductive sections 721, 731 for the ASIC 90 to be separately connected to the first quartz crystal resonator 80A and the second quartz crystal resonator 80B. In addition, the substrate 70 further has a first bond pad group 701 and a second bond pad group 702 at a bottom thereof, and the first and second bond pad groups 701, 702 are individually coupled to the ASIC 90 via the electric wires for the present invention to become a surface mount device (SMD).

(25) In FIG. 5, the integrated oscillator package 60 is mounted on a PCB P of a smartphone. In this application, the ASIC 90 has a switch control 91 to switch between different audio formats with different degree of hi-fidelity (hi-fi) to individually corresponds to a first clock rate 92 output from the first quartz crystal resonator 80A and to a second clock rate 93 output from the second quartz crystal resonator 80B, so as to form a structure of an integrated crystal oscillator package. In this embodiment, the switch control 91 has a first switch 911 and a second switch 912 to switch between the first clock rate 92 and the second clock rate 93 for output, or to simultaneously output both frequencies.

(26) FIG. 6A illustrates a circuit diagram of the present invention. Normally a hi-fi system requires two crystal oscillators; in other words, there are isolated connecting points for two electricity power suppliers VDD, two ground connections GND, two signal input controllers INH, and two frequency outputs F. However, in the present invention the crystal oscillators are integrated into one single package which only requires connecting points for one electricity power supplier VDD, one ground connection GND, one signal input controller INH, one first clock rate output FA, one second clock rate output FB, and one switch transmission input FS. That is, the present invention is highly integrated to have two crystal oscillators and one ASIC within one package. In this embodiment, the audio formats are 44.1 kHz and 48 kHz. The first clock rate 92 outputs a 44.1 kHz frequency and the second clock rate 93 outputs a 48 kHz frequency. Further referring to FIG. 6B, the first and second crystal quartz resonators 80A, 80B can individually output the frequency or simultaneously output both frequencies in operation; the first clock rate 92 outputs a frequency of 44.1 kHz or a multiple thereof, and the second clock rate 93 outputs a frequency of 48 kHz or a multiple thereof.

(27) To further elaborate features of the present invention, please see the following chart for comparison.

(28) TABLE-US-00002 Item A B C Conventional Conventional Conventional D package package integrated Integrated structure of structure of package of package of two crystal two crystal two crystal crystal resonators oscillators resonators oscillators (FIGS. (FIGS. (FIGS. (the present 1A-1B) 1C-1F) 1J-1M) invention) Quality Excellent Excellent Excellent Excellent factor Phase noise Poor Excellent Poor Excellent control Integration Fair Fair Excellent Excellent of different clock rates Covering Fair Fair Less Less area on a smartphone Costs for Fair High Low Fair parts

(29) As the control of phase noises is a vital factor in hi-fi system, items A and C are ruled out undoubtedly. The present invention further integrates the crystal oscillators with an ASIC as a package to retain the features of excellent quality of phase noise control to satisfy the requirements of hi-fi systems and meanwhile keep the features of better integration and less covering area on a smartphone, therefore reducing the costs for parts as well.

(30) In short, the present invention integrates the first and second crystal quartz resonators 80A, 80B and the ASIC 90, and keeps the feature of better phase noise control to achieve and satisfy the requirements of hi-fi systems; such structure also consumes lower costs for parts in the manufacturing process.

(31) Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except by the appended claims.