CN1179261C - Low electromagnetic interference clock oscillator module - Google Patents
Low electromagnetic interference clock oscillator module Download PDFInfo
- Publication number
- CN1179261C CN1179261C CNB01144455XA CN01144455A CN1179261C CN 1179261 C CN1179261 C CN 1179261C CN B01144455X A CNB01144455X A CN B01144455XA CN 01144455 A CN01144455 A CN 01144455A CN 1179261 C CN1179261 C CN 1179261C
- Authority
- CN
- China
- Prior art keywords
- clock
- motherboard
- pin
- clock generator
- coupled
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The present invention relates to a low electromagnetic interference clock oscillator module, which can be arranged on an oscillation embedded pad of a clock adhering to plastics or ceramics on a standard surface of a host board of a host device, and accordingly, the host board of the host device does not need to be redesigned, namely that the host device can be reformed. The present invention can make EMC radiation energy reduced to the extent of sufficiently pass the test of the EMC radiation energy. The oscillator is characterized in that a spread-spectrum EMC clock generator is adopted.
Description
Technical field
The present invention relates to adopt Electro Magnetic Compatibility (EMC, particularly low electromagnetic interference clock oscillator of an above oscillator with the digital electronic device of setting up clock (clock) signal.
Background technology
Such as the digital device of personal computer and tabulating machine etc., the clock that its sequential synchronization all relies on high frequency oscillator and produced.These clocks have the rise time fast, FOURIER (Fourier) power spectrum is had on the accurate broadband in quite high-power position one produce many frequency components.It is at the radio frequency band that these FOURIER components have many, can give off from signal circuit, ground plane, power lead and monitor cable line etc.The component of these radiation then can disturb contiguous Electrical and Electronic receiver, for example radio and TV.
In the U.S., FCC (FCC (Federal Communications Commission)) has issued the not enforceable electromagnetic interference (EMI) compatibility of tool (hereinafter to be referred as EMC) standard, when manufacturer is on sale throughout its product in the U.S. not necessity meet these standards.In addition, European authorities also issue the EMC standard, but its tool forced action type.According to European EMC instruction,, otherwise forbidden sell goods in the European Economic Community unless manufacturer meets these EMC standards.
The traditional product construction cycle often can not seeked advice from EMC design engineer during product design, the result, and after product was not by the EMC test, the beginning expected being engaged in the EMC design effort of lowering emittance often.These EMC attenuating work comprise and increase shielding, ground connection and increase EMC wave filter etc.Regrettably, the beginning was taked these measures after design has been finished already, and its cost is quite expensive, and the measure that can effectively be taked is also limited.For example, increase shielding, wave filter and more ground connection etc. are because must be to printed circuit board (PCB) layout again, so both consuming time also expensive.For high-tech product because product is out-of-date soon, so the kind social connections of releasing product with the market business opportunity, often all need aspect the release of Products Development cycle and product very rapid.Because it is faster, littler that scientific-technical progress impels industry constantly to release, low-power more, more high power capacity and more powerful technology be not so in the high-tech industry, the product life cycle is rare below 3 years.As a result, if time flower at the redesign product in the hope of meeting the EMC standard, may just become the whether successful havoc of product.Again around circuit and the wave filter that augments and the ground connection in footpath, all may make product increase the mistake that some must be found out and eliminate.Extra shielding is provided, also needs time and expense to go to develop in order to make the mould of new shielding parts.
Those skilled in the art will appreciate that the optimum method of elimination or reducing noise or electromagnetic interference (EMI), is exactly from the source reducing noise.By the product of EMC test, major part all is not because of the clock signal harmonic wave, the high frequency FOURIER component of clock signal and the radiation of dependence edge band noise, so that can't pass through, and this also is traceable to clock oscillator.
Can be the representative that is developed as with spectrum spread clock generator integrated circuit for the prior art of the tool meaning that lowers EMI so far, for example the U.S. the 5th, 488, and described in No. 627 patents, its shortcoming is:
1, its volume is big, makes the magnitude of current influence its effect greatly.
2, its entire circuit plate and coat without suitable isolation, and when entering in the tin stove of high temperature in welding, the electronic component on the circuit board is damaged Yin Gaowen, and causes fraction defective.
3, each the electronic component height on its circuit board differs, and when carrying out the robotization Assembling Production, can't make on the automation equipment sucker on the robotic arm with its sharp smoothly absorption, and causes the difficulty in the automated production.
Therefore, need a kind ofly can in the digital Design of finishing, reach the improvement clock oscillator that lowers radiation EMI easily fast, make these designs can be repacked into a new clock oscillator rapidly, so that do not need expensive and redesign consuming time, just can reach rapidly economically by harsh EMC emittance test.
Summary of the invention
The purpose of this invention is to provide a kind of low EMC emittance clock oscillator with following properties.
First, according to a kind of EMC clock oscillator that the present invention constituted is to belong to the plug-in module form, simultaneously itself have printed circuit board (PCB), so that will it not be designed into the main printed circuit board or the motherboard (to call motherboard in the following text) that various EMC problems may be designed into.This plug-in module is provided with four pads that extend from downside own, and these pads are to be separated into to paste the direct substitute that this module is used as standard plastic and ceramic package.The pad of this EMC clock oscillator module is to be separated into suitably to accept electric power and ground connection and suitably to accept the output clock signal on the pad on the pad.
The second, be the spectrum spread clock generator chip that utilizes a kind of present commercialization according to the low noise clock oscillator that the present invention constituted, so that expand the respectively frequency spectrum of this chip, thereby reduce the amplitude of clock harmonic wave.
The 3rd, comprise simulation and the digital grounding layer that itself is located on the clock oscillator module according to the low noise clock oscillator that the present invention constituted, these ground planes are to be coupling in together at the single-point that just in time is single pin junction from this module to motherboard.
The 4th, being included between clock oscillator module and motherboard according to the low noise clock oscillator that the present invention constituted has power supply gas to be connected the EMC wave filter of contacting separately with three.These three EMC wave filters can prevent that the power supply of host apparatus or any noise on the ground plane from arriving at the spectrum spread clock generator and be exaggerated and lower the noise component that the clock generator chip is produced, in order to avoid when arriving at the motherboard clock bus, still may further radiate.
The 5th, low noise clock oscillator according to one in the defined broad sense attribute of aforementioned four characteristics of the present invention attribute formation, except having aforementioned four characteristics, also have the mode of the capacitance that utilizes the change loop filter, use the ability that changes the every electrical characteristics of this clock oscillator.Change also will change the amplitude of clock harmonic wave during loop filter, make its cost that can broaden slightly at the frequency range of the FOURIER of each harmonic wave spectrum component and be divided into some segments attenuatings.In addition, utilize the routing from the integrated circuit to the setting-up piece to engage (WIREBOND1NG), just can utilize the filter characteristic of change clock generator and select to be intended to the mode of harmonic wave, use the change clock generator exporting selected quartz crystal frequency.Be with, needn't change quartz crystal, just can change the clock output frequency of this low noise clock module.
According to an aspect of the present invention, a kind of low electromagnetic interference clock oscillator is characterized in that comprising: a printed circuit board (PCB), this circuit board are provided with some conducting wires and separate with motherboard; One spectrum spread clock generator chip, this clock generator chip is provided with some terminals that are coupled to the scheduled circuit in the conducting wire, for producing a kind of spectrum spread clock signal; One quartz crystal is coupled to the circuit of being scheduled in the conducting wire of printed circuit board (PCB); Some by machinery and electrical couplings the pin of scheduled circuit in the conducting wire of printed circuit board (PCB), this pin is separated into and can joins standard plastic and ceramic surface on the motherboard to and paste specific pin socket in the encapsulation, be electrically connected and Vcc power supply on the motherboard and conducting wire, ground connection source are coupled to the spectrum spread clock generator to provide, and the spectrum spread clock signal is coupled to clock bus on the motherboard, provide the pad that is electrically connected to be made into to make printed circuit board (PCB) to contact with any conducting wire on the motherboard up and not, be electrically connected via single pin and be connected to conducting wire, ground connection source; Some EMC wave filters are in order to be coupled to each pin the predetermined terminal of spectrum spread clock generator.
According to another aspect of the present invention, a kind of low electromagnetic interference clock oscillator, it is characterized in that comprising: a slice separates and is provided with the tellite of a ground plane with motherboard, this tellite be provided with separately numeral and analogue ground layer line road, the analogue ground layer is connected to the analogue ground output terminal, and the digital grounding layer then is connected to the digital grounding output terminal, in addition, tellite is provided with some pins that are electrically connected in addition, and pin has a physical arrangements and sets and layout; Stick on this substrate so that produce the clock generator chip of spectrum spread clock signal from the reference clock signal; The clock generator chip has the analogue ground output terminal of a mimic channel wiring and the digital output end of a digital wiring, be connected respectively to described analogue ground layer line road and described digital grounding layer line road that described tellite branch is arranged, by electrical engagement, this ground connection pin is connected electrically to an earth bus of motherboard via standard DIP integrated circuit socket in the position of a ground connection pin for described simulation and digital grounding layer.
According to a further aspect of the invention, a kind of low electromagnetic interference clock oscillator for the standard DIP clock oscillator socket that inserts motherboard, it is characterized in that comprising: a slice separates and is provided with the tellite of a ground plane with motherboard; Stick on this substrate so that produce the clock generator chip of spectrum spread clock signal from the reference clock signal; First connector is in order to provide a single-point to be electrically connected and this ground plane is coupled to the earth terminal of clock generator chip connecing of the ground plane of tellite and motherboard between the conducting wire; Second connector is electrically connected in order to provide the spectrum spread clock signal that is electrically connected and the clock generator chip is produced and the clock bus on the motherboard to provide between power supply of motherboard and clock generator chip.
And the present invention has following advantage:
1, the present invention suitably is divided into more than one part with entire circuit, and with being encapsulated of height different levels, and whole area is significantly dwindled, in order to the demand that is suitable for more dwindling present electronic product volume day.
2, as above-mentioned, after volume-diminished, the magnitude of current thereon also reduces relatively, and promotes its effect.
3, entire circuit is by suitable encapsulation, and forms a separation layer, when avoiding carrying out welding sequence in high temperature tin stove, is subjected to high temperature and damages.
4, entire circuit is by suitable encapsulation, and forms a more flat plane, and the robotic arm sucker is drawn assembling on the automation equipment when carrying out the robotization Assembling Production, and the Dary is in the robotization Assembling Production.
In order more to understand architectural feature of the present invention and effect thereof, the present invention is described in detail with way of example below in conjunction with accompanying drawing.
Description of drawings
Fig. 1 is the vertical view of a kind of ceramic clock module of constituting according to attribute of the present invention.
Fig. 2 is plastics of the present invention and the ceramic resonator module cut-away view when being secured on the motherboard of main frame.
The internal circuit wiring diagram of Fig. 3 module of the present invention wherein demonstrates numeral and analogue ground circuit and single-point grounding.
Fig. 4 is that the plastics and the ceramic resonator module of two kinds of different sizes of the present invention is how to be secured on the motherboard of main frame, and the ground plane circuit of this module is above the ground plane circuit of motherboard, the stereographic map that only has single-point to connect.
Fig. 5 is a calcspar of the preferred embodiment of oscillator of the present invention, wherein shows the PINOUT and use situation of EMC wave filter at each electric coupling point that is coupled to motherboard.
Fig. 6 is the diagram figure of low noise clock oscillator module shown in Figure 1.
Fig. 7 shows has the EMC emittance that EMC clock generator module that 20MHZ imports electric frequency caused and the comparison diagram of standard quartz crystal clock oscillator among Fig. 1.
Drawing reference numeral explanation: 10 printed circuit board (PCB)s; 12 digital grounding layers (module ground plane); 14 analogue ground layers; 16 conducting wires point; 18,20,22,24,36,38,4 pads; 26 motherboards; 27 contacts; 271 scolding tin; 30 clock generator chips; 32 quartz crystals; The 36LF wave filter; 40,42 circuits; 44,46,50E MC wave filter; 48 lines.
Embodiment
Seeing also Fig. 1, is the vertical view of a kind of low electromagnetic interference clock oscillator module of constituting according to attribute of the present invention.This clock oscillator module has the printed circuit board (PCB) 10 of itself, and 10 of this printed circuit board (PCB)s have digital grounding layer line road (GROUND PLANETRACE) and the analogue ground layer line road (as shown in Figure 3) of itself.
Referring to Fig. 2 and Fig. 3, be that plastics of the present invention and ceramic clock oscillator module cuing open when being secured on the motherboard 26 of main frame shown and the inner conductive circuit of printed circuit board (PCB) 10.Digital grounding layer 12 and analogue ground layer 14 are to give entity and electrical engagement at single conducting wire point 16, and are electrically connected to pin shown in Figure 1 18.Clock oscillator module has four pads (PAD) 18,20,22 and 24 that extend from this module downside, these four pads 18,20,22 of mat and 24 and motherboard 26 on contact 27 when pasting with scolding tin 271, and make 26 formation of this clock oscillator module and motherboard, one suitable spacing.
Seeing also shown in Figure 4ly again, is the mode that EMC (Electro Magnetic Compatibility) clock oscillator module inserts the digital circuit motherboard 26 of arbitrary host apparatus.This EMC clock oscillator module is to paste pad 18,20,22 and 24 with the surface on four pads that paste standard plastic or ceramic package, and obtains mechanical supports and be connected electrically to this motherboard 26 from motherboard 26.During stickup, except motherboard 26 ground planes with single-point between the oscillator module ground plane is connected, the ground plane circuit of clock oscillator module all above motherboard 26 ground plane circuits and with its insulation.The plastics of standard or ceramic package are to be represented by two parallel lines that are the pad of representative with pad 18, and by the conducting wire of electrical couplings to motherboard 26, so that provide power supply to connect to traditional clock generator chip 30, clock bus on the motherboard 26 is provided connection and provides more than one ground connection to motherboard 26 digital grounding layers, 12/ circuit pad 18 and motherboard 26 analogue ground layers 14 or circuit.Four pads 18,20,22 and 24 that extend from the oscillator module downside, on size and interval each other is to be set as to embed plastics and ceramic package, suitable pin socket, so that it is except ground connection, all identical with standard time clock generator chip 30 to being connected of power supply, ground and clock bus.According to a kind of low noise clock module that training centre of the present invention constitutes, be from single point at this moment the clock module numeral and analogue ground floor 12,14 to simulation and digital grounding layer line road (these circuits answer motherboard to give electrical engagement) indirectly.This measure for example can be sent the public impedance of noise for any EMI (electromagnetic interference (EMI)) problem on motherboard 26 ground planes, ground loop, or eddy current etc. all have and can prevent that it can't be coupled to the advantage of the ground plane or the circuit of clock oscillator module.If these ground loops on motherboard 26 ground planes are coupled to the ground plane of EMC clock oscillator module, will be because of the ground connection reference voltage that changes the EMC frequency, and, cause these ground loops energy by (amplification) the output signal of noise injection clock generator.So this output signal that is loaded with noise that sends from clock generator is coupled to the clock bus of motherboard 26, can work at the radiating antenna place when the time comes, use the emittance (EMISSION) that increases EMC.Only utilize from some the ground plane of this low noise clock oscillator is coupled to the mode of motherboard 26 ground plane circuits, can eliminate this noise mechanism.
Please consult Fig. 1 once more, it shows a spectrum spread clock generator chip 30 in printed circuit board (PCB) 10 central authorities.This clock generator chip 30 is to be coupled to a quartz crystal 32 of setting basic frequency for this chip.The function of clock generator chip 30 is FOURIER (Fourier) power spectrums of each harmonic wave of expansion, uses the total electric energy that keeps each harmonic wave, thereby lowers the amplitude of each clock harmonic wave.Because the test of EMC emittance is only concluded critical amplitudes position standard (these amplitude position standards are to reduce along with increasing of frequency band) to the EMC emittance of various different frequencies, so this measure helps digital product to pass through these tests.Make the mode of the amplitude attenuating of each clock harmonic wave with spread spectrum, just can allow some digital products test by original unpassable EMC emittance.EMC clock oscillator according to training centre formation of the present invention, its modularization is inserted an advantage of alternative form, be exactly need not spend any time, furnish funds for to redesign product, for example again around footpath (RE-ROUTING), augment shielding and more ground connection etc., just can allow the spectrum spread clock generator of present commercialization be adapted to main frame 0 system that does not test through transformation by EMC.When only not testing (EMI test), be enough to make this product to pass through just only use spectrum spread clock generator technology instead by electromagnetic radiation energy because of difference 1-2DB as fruit product.
Also comprise the some change-over switches (SWITCH) on the printed circuit board (PCB) of this oscillator according to the low electromagnetic interference clock oscillator that the present invention constituted, the situation of these change-over switches can be changed, and uses the clock frequency output that changes this low noise clock oscillator.These change-over switches are to take the form of conductive spacer, are representative with pad 36 and 38 wherein.It is to utilize some circuits that some right pads are arranged, and is representative with circuit 40 and 42 wherein, and is electrically connected together, but most pad is to be coupled to spectrum spread clock generator chip 30.Utilization engages (WIREBONDING mode from the routing that spectrum spread clock generator chip 30 joins each conductive spacer on the printed circuit board (PCB) 10 to, the frequency that just can change each inner wave filter in the spectrum spread clock generator chip 30 is selected pass-band performance, and select various basic output frequency harmonic wave, use the clock signal output frequency that changes oscillator module.Another critical function of LF (low frequency) wave filter 36, the change that is electric capacity will change the propagation of clock harmonic spectrum, so that sectional is controlled the propagation of these harmonic waves.Can prove fully that from document when the clock harmonic frequency had its spread spectrum, the amplitude of the basic frequency in the FOURIER frequency spectrum just lowered.Spread spectrum big more, it is many more that amplitude just lowers.If some circuit is cut off, just sectional increases the spread spectrum amount.When the spread spectrum amount increases, just according to the amplitude that lowers the primary harmonic of being expanded.This measure helps available EMC clock oscillator to transform the main computer boxes of within an ace of and not testing by EMC.Though the EMC clock oscillator lowers the degree of EMC emittance can be up to 20DB,, the clock harmonic spectrum is expanded to above it by the required degree of EMC emittance test if when an only poor 4DB so do not done by the product of EMC test.If the expansion of the frequency spectrum of clock signal is too severe, may make error or other fault of some microprocessors inefficacies or generation intermittence.Therefore, for only surpassing a little clock harmonic amplitude of EMC fixed limit, preferable way is to be enough to make main computer boxes easily by the EMC test, to test under the principle of required degree by EMC but be no more than it, allowing this amplitude can lower several DB.The error that this measure can make in the main frame digital circuit components expansion because of the clock signal frequency spectrum produce in the elsewhere minimizes or eliminates fully.
Fig. 5 is a calcspar of oscillator preferred embodiment, wherein demonstrates the EMC wave filter in PINOUT of each electric coupling point that is coupled to motherboard 26 (pin external characteristics) and use situation.Clock generator itself has with quartz crystal 32 defined basic frequencies, and pastes the EMC wave filter 44 of encapsulation and pad 4 and be coupled to a Vcc (supply voltage) power supply via standard plastic and ceramic surface.EMC wave filter 44 can prevent that the EMC noise in the Vcc power supply from arriving at clock generator chip 30, and is exaggerated with being coupled to clock bus through injecting clock signal.The pin of clock generator chip 30 is via EMC wave filter 46 and the single-point grounding by the 7th pin of standard 14 pin formula DIP (double-row type encapsulation), and is coupled to the ground plane of module ground plane 12 and motherboard 26.EMC wave filter 46 can prevent that any ground loop or other coupling noise on motherboard 26 ground planes is exaggerated with being coupled to clock bus to clock generator chip 30 with through injecting clock signal, so that is radiated EMC test receiver.Clock generator chip 30 output clock signals on the line 48 are to be coupled to motherboard 26 clock bus via the 3rd pin of package layout again by EMC wave filter 50.EMC wave filter 50 can suppress any EMC noise component (COMPONENT) in the clock signal, causes them can not arrive at motherboard 26 clock bus and give off.
Fig. 6 is the diagram figure of oscillator module shown in Figure 1.Clock generator chip 30 can accept 6 to the incoming frequency of 160MHZ, and the output clock frequency then can be equivalent to the mark or the multiple of incoming frequency, and this output frequency can be selected between 6 to 160MHZ.This clock generator chip 30 has an internal oscillator of being located on the circuit board, and its frequency is set by the arbitrary quartz crystal that is coupled to the 12nd and 13 pins or other parallel resonance circuit.Modulated output clock signal is the 5th, 6 and 7 pins that appear at clock generator chip 30.The 2nd and 10 pins then are to announce and be incorporated into this chart with reference pattern according to chip maker, for being used for frequency multiplication.The LF signal is the phase-detecting output of clock signal.It is a single-ended ternary output, can be for being used as loop error signal.The REFOUT signal is the buffering output of a quartz crystal or frequency input reference.The electric capacity of LF wave filter 36 can be determined spread spectrum modulation amount, the reduced amounts of may command clock harmonic amplitude according to this.The 14th and 15 pins are in order to the controlled frequency input range.Use the change-over switch of ground connection or use Vcc (logical one), these different control pins are just controlled the running of clock generator chip 30, control the modulation amount according to this, the setting and the frequency input range of frequency input multiplier.
See also shown in Figure 7, be to have the EMC emittance that EMC clock generator module that 20MHZ imports electric frequency caused and the comparison diagram of standard crystal clock oscillator among Fig. 1, wherein the longitudinal axis is the amplitude of EMC emittance, and is unit with DB, and transverse axis then is the frequency of emittance.Fine rule is represented the emittance of EMC clock oscillator module, and thick line is then represented the EMC emittance of standard crystal oscillator when different frequency.In sum, tool of the present invention provides that volume is little, the magnitude of current decreases in when carrying out welding sequence in the high temperature tin stove, be not subjected to high temperature and damage and profit when carrying out the robotization Assembling Production on the automation equipment robotic arm sucker drawn Assembling Production person.
Claims (10)
1, a kind of low electromagnetic interference clock oscillator is characterized in that comprising:
One printed circuit board (PCB), this circuit board are provided with some conducting wires and separate with motherboard;
One spectrum spread clock generator chip, this clock generator chip is provided with some terminals that are coupled to the scheduled circuit in the conducting wire, for producing a kind of spectrum spread clock signal;
One quartz crystal is coupled to the circuit of being scheduled in the conducting wire of printed circuit board (PCB);
Some by machinery and electrical couplings the pin of scheduled circuit in the conducting wire of printed circuit board (PCB), this pin is separated into and can joins standard plastic and ceramic surface on the motherboard to and paste specific pin socket in the encapsulation, be electrically connected and Vcc power supply on the motherboard and conducting wire, ground connection source are coupled to the spectrum spread clock generator to provide, and the spectrum spread clock signal is coupled to clock bus on the motherboard, provide the pad that is electrically connected to be made into to make printed circuit board (PCB) to contact with any conducting wire on the motherboard up and not, be electrically connected via single pin and be connected to conducting wire, ground connection source;
Some EMC wave filters are in order to be coupled to each pin the predetermined terminal of spectrum spread clock generator.
2, a kind of low electromagnetic interference clock oscillator is characterized in that comprising:
A slice separates and is provided with the tellite of a ground plane with motherboard, this tellite be provided with separately numeral and analogue ground layer line road, the analogue ground layer is connected to the analogue ground output terminal, the digital grounding layer then is connected to the digital grounding output terminal, in addition, tellite is provided with some pins that are electrically connected in addition, and pin has a physical arrangements and sets and layout;
Stick on this substrate so that produce the clock generator chip of spectrum spread clock signal from the reference clock signal;
The clock generator chip has the analogue ground output terminal of a mimic channel wiring and the digital output end of a digital wiring, be connected respectively to described analogue ground layer line road and described digital grounding layer line road that described tellite branch is arranged, by electrical engagement, this ground connection pin is connected electrically to an earth bus of motherboard via standard DIP integrated circuit socket in the position of a ground connection pin for described simulation and digital grounding layer.
3, low electromagnetic interference clock oscillator as claimed in claim 2 is characterized in that also comprising:
The change-over switch device, be coupled to the clock generator chip, so that segmentation is controlled this clock generator chip to the performed spread spectrum modulation amount of reference clock signal with control the incoming frequency scope of the reference clock signal of each discrete range, and the frequency multiplication amount of control clock reference signal.
4, low electromagnetic interference clock oscillator as claimed in claim 2 is characterized in that the clock generator chip has a power input and the output terminal of clock that the clock signal that is produced can be exported; Except the ground connection pin, be electrically connected pin and also comprise a power pin that can be coupled to the power bus on the motherboard via integrated circuit socket, with an output connecting pin that can be coupled to the clock bus on the motherboard via integrated circuit socket, other comprises the some EMC wave filters that stick on the tellite, so that power pin, ground connection pin and output connecting pin are coupled to the power take-off of clock generator chip, ground connection output terminal and output terminal of clock respectively.
5,, it is characterized in that being electrically connected pin and be separated and be arranged to and to insert standard plastic and ceramic surface on the motherboard and paste specific pin socket in the encapsulation as claim 2 a described low electromagnetic interference clock oscillator.
6, low electromagnetic interference clock oscillator as claimed in claim 3 is characterized in that being electrically connected pin and is separated and is arranged to and can insert standard plastic and ceramic surface on the motherboard and paste specific pin socket in the encapsulation.
7, low electromagnetic interference clock oscillator as claimed in claim 4 is characterized in that being electrically connected pin and is separated and is arranged to and can insert standard plastic and ceramic surface on the motherboard and paste specific pin socket in the encapsulation.
8, a kind of low electromagnetic interference clock oscillator for the standard DIP clock oscillator socket that inserts motherboard is characterized in that comprising:
A slice separates and is provided with the tellite of a ground plane with motherboard;
Stick on this substrate so that produce the clock generator chip of spectrum spread clock signal from the reference clock signal;
First connector is in order to provide a single-point to be electrically connected and this ground plane is coupled to the earth terminal of clock generator chip connecing of the ground plane of tellite and motherboard between the conducting wire;
Second connector is electrically connected in order to provide the spectrum spread clock signal that is electrically connected and the clock generator chip is produced and the clock bus on the motherboard to provide between power supply of motherboard and clock generator chip.
9, as claim 9 a described low electromagnetic interference clock oscillator, it is characterized in that also comprising:
The change-over switch device, in order to segmentation control clock generator to the performed spread spectrum modulation amount of reference clock signal with control the incoming frequency scope of the reference clock signal of each discrete range, and the frequency multiplication amount of control clock reference signal;
10, low electromagnetic interference clock oscillator as claimed in claim 9, it is characterized in that also comprising the some EMC wave filters that stick on the tellite, so that the power ground conducting wire of motherboard and clock bus are coupled to each respective end of clock generator separately.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB01144455XA CN1179261C (en) | 2001-12-18 | 2001-12-18 | Low electromagnetic interference clock oscillator module |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB01144455XA CN1179261C (en) | 2001-12-18 | 2001-12-18 | Low electromagnetic interference clock oscillator module |
Publications (2)
Publication Number | Publication Date |
---|---|
CN1387100A CN1387100A (en) | 2002-12-25 |
CN1179261C true CN1179261C (en) | 2004-12-08 |
Family
ID=4677595
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CNB01144455XA Expired - Fee Related CN1179261C (en) | 2001-12-18 | 2001-12-18 | Low electromagnetic interference clock oscillator module |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN1179261C (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100485932C (en) * | 2005-12-22 | 2009-05-06 | 株式会社东芝 | Semiconductor device and electric apparatus |
CN101399530B (en) * | 2007-09-27 | 2010-11-17 | 立锜科技股份有限公司 | Circuit and method for frequency interference according to load |
CN106849936A (en) * | 2017-03-14 | 2017-06-13 | 苏州格美芯微电子有限公司 | A kind of new structure for eliminating digital circuit blocks and clock module interference |
CN113517878A (en) * | 2021-06-09 | 2021-10-19 | 包头市稀宝博为医疗系统有限公司 | Implementation method and device for improving EMC (electro magnetic compatibility) of clock signal |
-
2001
- 2001-12-18 CN CNB01144455XA patent/CN1179261C/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
CN1387100A (en) | 2002-12-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8716851B2 (en) | Continuously referencing signals over multiple layers in laminate packages | |
US7509615B2 (en) | Circuit layout structure and method | |
CN106558748A (en) | For transmitting signals to the system in dielectric waveguide | |
CN101448360A (en) | Multi-layer printed circuit board | |
Ricchiuti | Power-supply decoupling on fully populated high-speed digital PCBs | |
WO2006110868A2 (en) | Inductor | |
JPH1041421A (en) | Packaging assembly | |
CN100490604C (en) | Printing circuit board | |
US20160240909A1 (en) | Right Angle Transition to Circuit | |
CN110110393B (en) | System simulation selection method and system | |
CN1179261C (en) | Low electromagnetic interference clock oscillator module | |
CN101110578B (en) | Adjustable-inductance filter, tape distribution substrate comprising the filter, and display panel assembly comprising the tape distribution substrate | |
Pak et al. | Modeling and measurement of radiated field emission from a power/ground plane cavity edge excited by a through-hole signal via based on a balanced TLM and via coupling model | |
US20200100355A1 (en) | Multilayer ceramic electronic package with modulated mesh topology | |
CN109655733A (en) | The method of non-destructive testing millimeter wave bga component | |
KR20030064830A (en) | Interconnect | |
US11071197B2 (en) | Multilayer ceramic electronic package with modulated mesh topology and alternating rods | |
Liang et al. | Application of digital PGA technology to K-band microcircuit and microwave subsystem packages | |
US9831540B2 (en) | Systems and methods for improved chip device performance | |
Kangasvieri et al. | Low-loss and wideband package transitions for microwave and millimeter-wave MCMs | |
Zahid et al. | Signal integrity simulation design and analysis of electronic article surveillance PCB for RFID applications | |
Pitschi et al. | An approach to accurate measurements of the electrical characteristics of SAW RF filters using neutral test environments | |
JP3086133U (en) | Low electromagnetic interference clock oscillator module | |
CN108631033A (en) | Minimize SIW surface-mount type circulators | |
Zongjie et al. | High density microwave interface interconnection based on elastic fuzz buttons |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
C19 | Lapse of patent right due to non-payment of the annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |