CN103717012A - PCB board via impedance control method and structure - Google Patents
PCB board via impedance control method and structure Download PDFInfo
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- CN103717012A CN103717012A CN201210371871.5A CN201210371871A CN103717012A CN 103717012 A CN103717012 A CN 103717012A CN 201210371871 A CN201210371871 A CN 201210371871A CN 103717012 A CN103717012 A CN 103717012A
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Abstract
The invention discloses a PCB board via impedance control method and structure. A non-functional pad, which is abandoned by the industry, on a PCB board is reused. The non-functional pad is arranged on another layer beyond a wire outgoing layer which is connected with a via, so as to adjust the balance of metal pads on a via transmission path. The consistency of distribution capacitors per unit length is improved. According to the invention, the defect of the existing via impedance control technology at present can be significantly improved, and the purpose of improving the overall network communication signal quality of the PCB board is realized.
Description
Technical field
The present invention relates to communication technical field, relate in particular to method and structure that a kind of pcb board through hole impedance is controlled.
Background technology
PCB(Printed Circuit Board) plate is important parts in communication equipment, is the supporter of electronic devices and components and the supplier of electrical connection.Along with the electronic signal speed of pcb board carrying communication is more and more higher, the electronic circuit on pcb board need to carry out impedance Control to guarantee electronic signal quality.By adjusting stack design and the routing line width of each layer of pcb board, can realize the accurate control to the different resistance values of pcb board cabling.The common way of industry is to control according to single-ended cabling 50 Ω, difference cabling 100 Ω at present.The Technology of ZO control of pcb board cabling is very ripe.The cabling of pcb board different layers is connected to become the communication network (as shown in Figure 1) communicating with each other by via hole.Via hole, as the important component part of PCB communication network, itself has the distribution impedance characteristic the same with PCB cabling.And via hole is only the maximum discontinuity point of PCB circuit network middle impedance place conventionally.Along with pcb board traffic rate enters the GHz epoch, through hole impedance control technology becomes the key technology that guarantees pcb board signal of communication quality day by day.
The modal through hole impedance control technology of industry as shown in Figure 2, is improved whole via hole electrical characteristic by controlling anti-pad size size.By 3D electromagnetic-field simulation, we can determine best anti-pad size size.Yet as shown in Figure 3, emulation shows that through hole impedance is not uniformity, but presents distributed change in resistance.The desired value that through hole impedance departs from 50 Ω in the anti-pad design situation of the best still has the deviation of positive and negative 2.5 ohm, and this deviation is the intrinsic error of existing impedance adjustment, cannot continue to promote impedance Control precision.
Summary of the invention
In view of this, the present invention is on the conventional through hole impedance control technology of current industry basis, propose a kind of through hole impedance control technology of novelty, can significantly improve the defect of existing through hole impedance control technology, thereby reach the object of improving overall network signal of communication quality.
For realizing the object of the invention, implementation of the present invention is specific as follows:
A kind of method that pcb board through hole impedance is controlled, for the through hole impedance on pcb board is accurately controlled, wherein, other layers outside the outlet layer being connected with via hole are provided with non-functional pad, to regulate the harmony of metal pad on via hole transmission path, thereby improve the consistency of unit length distributed capacitance.
Further, on described pcb board via hole, also include top layer ordinary pads, outlet layer ordinary pads and anti-pad.
Further, relation between the size of the top layer ordinary pads on described pcb board via hole, outlet layer ordinary pads, non-functional pad, anti-pad size and top layer ordinary pads, outlet layer ordinary pads, non-functional pad and anti-pad size size is by adopting 3D electromagnetic-field simulation to calculate.
Further, described method also comprises: optimize PCB stepped construction, make the spacing between each layer consistent, thereby the ordinary pads and the non-functional pad that reach on via hole transmission path are uniformly distributed.
Further, described method also comprises: the surrounding at described pcb board via hole further arranges the ground via hole that control signal refluxes, by the through-hole structure change pcb board via hole of ground via hole and the electromagnetic field between ground via hole, distribute, thereby reach the object of improving signal via impedance Control precision.
The structure that the present invention provides a kind of pcb board through hole impedance to control simultaneously, for improving the impedance Control precision of pcb board via hole, wherein, described pcb board via structure includes: non-functional pad, be distributed in other layers outside the outlet layer being connected with via hole, to regulate the harmony of metal pad on described via hole transmission path, thereby improve the consistency of unit length distributed capacitance.
Further, on described pcb board via structure, also include top layer ordinary pads, outlet layer ordinary pads and anti-pad.
Further, relation between the size of the top layer ordinary pads on described pcb board via structure, outlet layer ordinary pads, non-functional pad, anti-pad size and top layer ordinary pads, outlet layer ordinary pads, non-functional pad and anti-pad size size is by adopting 3D electromagnetic-field simulation to calculate.
Further, by optimizing PCB stepped construction, make the spacing between each layer consistent, thereby ordinary pads and non-functional pad on via hole transmission path are equidistantly uniformly distributed.
Further, surrounding at described PCB via structure is further provided with the ground via hole that control signal refluxes, by the through-hole structure change signal via of ground via hole and the electromagnetic field between hole, ground, distribute, thereby reach the object of improving signal via impedance Control precision.
Compare with existing technical scheme, what the present invention can be by the distributed capacitance designing and making of via hole is more even, thus the via hole distribution impedance of realizing very high degree of precision control, thereby improve single board communication signal quality.
Accompanying drawing explanation
Fig. 1 is the structural representation of existing scheme multi-layer PCB board via hole.
Fig. 2 is that existing scheme is controlled the Multi-layer PCB structure schematic diagram of through hole impedance by anti-pad.
Fig. 3 is that existing scheme shows different anti-pad size through hole impedances control design sketchs by emulation.
Fig. 4 is the conventional via hole manufacture craft of existing scheme pcb board structural representation.
Fig. 5 is that pcb board via hole of the present invention is with equally distributed non-functional pad structural representation.
Fig. 6 is that pcb board backflow of the present invention ground via hole is evenly distributed on signal via around to assist the structural representation of impedance Control.
Fig. 7 is that the present invention shows different anti-pad size through hole impedances control design sketchs by emulation.
Embodiment
Still take the pcb board shown in Fig. 2 as example, and the making of the signal via of pcb board, generally comprises following control index:
1, boring aperture (Drill Diamater)
2, electroplating thickness (Plated)
3, ordinary pads (Regular Pad)
4, heat dissipation bonding pad (Thermal Relief)
5, anti-pad (Anti Pad)
Wherein ordinary pads is mainly used in outlet layer and the top layer of pcb board, and the ordinary pads of outlet layer can strengthen the mechanical connection performance between PCB cabling and metallic vias, is conducive to PCB machining and makes.Other layer of ordinary pads outside skim-coat and outlet layer is called non-functional pad.Theoretical according to signal integrity, non-functional pad, as the anchoring wire (Stub) of communication link, can affect effective transmission of signal.Industry standing procedure is for many years to delete the non-functional pad of each interlayer of pcb board to improve the electric property of signal via.
In existing scheme, because internal layer non-functional pad is generally deleted by pcb board processing factory as anchoring wire, therefore, signal via metal pad in vertical direction distributes and is inhomogeneous.Take the via structure shown in Fig. 4 as example, and between pcb board two outlet layer ordinary pads, long one section of via structure does not have the common metal pad of horizontal direction, causes the metal pad skewness on via hole transmission path.According to Theory of Electromagnetic Field, there is capacity effect in two metal guides cognition adjacent in space.Can there is distributed capacitance and distributed inductance in unit length conductor, both comprehensive functions form distribution impedance.The uneven distribution of metal pad means that the distributed capacitance of via hole cannot keep in balance unanimously, causes distribution impedance also cannot guarantee balanced consistent.Through hole impedance certainly exists discontinuous situation.
And for signal via, industry wishes that impedance approaches target control value as far as possible, also wish that the resistance value of via hole transmission path is consistent as much as possible simultaneously.If impedance changes, also wish that the amplitude changing is the smaller the better.Because through hole impedance control precision is higher, the impedance consistency of veneer network is better, and so, signal energy loss is less, and signal fidelity is higher, and veneer network signal quality is better.
Owing to determining that the conforming basic factor of impedance is unit length distributed capacitance.For this reason, the method that the pcb board through hole impedance that the present invention adopts is controlled is: re-use the non-functional pad on the pcb board of being given up by industry, by other layers outside the PCB outlet layer being connected with via hole, non-functional pad is set, to regulate the harmony of metal pad on via hole transmission path, thereby improve the consistency of unit length distributed capacitance.
In order to obtain best ordinary pads size design, guarantee the control effect of through hole impedance.The size that needs in the present invention to adopt 3D electromagnetic-field simulation to calculate pcb board top layer ordinary pads, outlet layer ordinary pads, non-functional pad, anti-pad size and the relation between pcb board top layer ordinary pads, outlet layer ordinary pads, non-functional pad and anti-pad size size.According to the final pcb board through hole impedance control structure forming of the present invention as shown in Figure 5.
Further, for the ease of other layers outside pcb board outlet layer, increase equally spacedly non-functional pad, preferably, the method that pcb board through hole impedance of the present invention is controlled also comprises: optimize PCB stepped construction, make the spacing between each layer of pcb board consistent, thereby the ordinary pads and the non-functional pad that reach on via hole transmission path are equidistantly uniformly distributed.
Further, in order to obtain best through hole impedance control precision performance, as shown in Figure 6, described method further arranges at pcb board the ground via hole that control signal refluxes around, by the through-hole structure change signal via of ground via hole and the electromagnetic field between hole, ground, distribute, thereby reach the object of improving signal via impedance Control precision.
As shown in Figure 7, by the inventive method, pcb board via hole is optimized to distribution, the size of non-functional pad, can be so that the control precision of through hole impedance reaches in the positive and negative 0.75 ohm of scope of target impedance, compared to the control precision of positive and negative 2.5 ohm of prior art, control precision has the lifting of 3 times.
The structure that the present invention provides a kind of pcb board through hole impedance to control simultaneously, for improving the impedance Control precision of pcb board via hole.Wherein said pcb board via structure comprises:
Non-functional pad, is distributed between other layers outside pcb board outlet layer, to regulate the harmony of metal pad on described via hole transmission path, thereby improves the consistency of unit length distributed capacitance.
Further, on described pcb board via structure, also include top layer ordinary pads, outlet layer ordinary pads and anti-pad.
Further, relation between the size of the top layer ordinary pads on described pcb board via structure, outlet layer ordinary pads, non-functional pad, anti-pad size and top layer ordinary pads, outlet layer ordinary pads, non-functional pad and anti-pad size size is by adopting 3D electromagnetic-field simulation to calculate.
Further, by optimizing PCB stepped construction, make the spacing between each layer consistent, thereby ordinary pads and non-functional pad on via hole transmission path are equidistantly uniformly distributed.
Further, surrounding at described PCB via structure is further provided with the ground via hole that control signal refluxes, by the through-hole structure change signal via of ground via hole and the electromagnetic field between hole, ground, distribute, thereby reach the object of improving signal via impedance Control precision.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of making, be equal to replacement, improvement etc., within all should being included in the scope of protection of the invention.
Claims (10)
1. the method that a pcb board through hole impedance is controlled, for the through hole impedance on pcb board is accurately controlled, it is characterized in that, the method comprises: other layers outside the outlet layer being connected with via hole arrange non-functional pad, to regulate the harmony of metal pad on via hole transmission path, thereby improve the consistency of unit length distributed capacitance.
2. the method for claim 1, is characterized in that, also includes top layer ordinary pads, outlet layer ordinary pads and anti-pad on described pcb board via hole.
3. method as claimed in claim 2, it is characterized in that, relation between the size of the top layer ordinary pads on described pcb board via hole, outlet layer ordinary pads, non-functional pad, anti-pad size and top layer ordinary pads, outlet layer ordinary pads, non-functional pad and anti-pad size size is by adopting 3D electromagnetic-field simulation to calculate.
4. the method as described in claim 1,2 or 3, is characterized in that, described method also comprises: optimize PCB stepped construction, make the spacing between each layer consistent, thereby the ordinary pads and the non-functional pad that reach on via hole transmission path are uniformly distributed.
5. method as claimed in claim 4, it is characterized in that, described method also comprises: the surrounding at described pcb board via hole further arranges the ground via hole that control signal refluxes, by the through-hole structure change pcb board via hole of ground via hole and the electromagnetic field between ground via hole, distribute, thereby reach the object of improving signal via impedance Control precision.
6. the structure that pcb board through hole impedance is controlled, for improving the impedance Control precision of pcb board via hole, is characterized in that, described pcb board via structure includes:
Non-functional pad, is distributed in other layers outside the outlet layer being connected with via hole, to regulate the harmony of metal pad on described via hole transmission path, thereby improves the consistency of unit length distributed capacitance.
7. structure as claimed in claim 6, is characterized in that, also includes top layer ordinary pads, outlet layer ordinary pads and anti-pad on described pcb board via hole.
8. structure as claimed in claim 7, it is characterized in that, relation between the size of the top layer ordinary pads on described pcb board via hole, outlet layer ordinary pads, non-functional pad, anti-pad size and top layer ordinary pads, outlet layer ordinary pads, non-functional pad and anti-pad size size is by adopting 3D electromagnetic-field simulation to calculate.
9. the structure as described in claim 6,7 or 8, is characterized in that, by optimizing PCB stepped construction, makes the spacing between each layer consistent, thereby ordinary pads and non-functional pad on via hole transmission path are equidistantly uniformly distributed.
10. structure as claimed in claim 9, it is characterized in that, surrounding at described PCB via structure is further provided with the ground via hole that control signal refluxes, by the through-hole structure change signal via of ground via hole and the electromagnetic field between hole, ground, distribute, thereby reach the object of improving signal via impedance Control precision.
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| CN201210371871.5A CN103717012B (en) | 2012-09-28 | 2012-09-28 | A kind of method and structure of PCB board via impedance control |
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| CN201210371871.5A CN103717012B (en) | 2012-09-28 | 2012-09-28 | A kind of method and structure of PCB board via impedance control |
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| CN103717012B CN103717012B (en) | 2018-05-18 |
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| CN103995941A (en) * | 2014-06-06 | 2014-08-20 | 无锡市同步电子科技有限公司 | Isolating setting method of pore impedance matching in high-speed circuit design |
| CN104023474A (en) * | 2014-06-24 | 2014-09-03 | 浪潮电子信息产业股份有限公司 | Method for alleviating influence of impedance mutation on signal transmission line quality |
| CN104202905A (en) * | 2014-09-28 | 2014-12-10 | 浪潮(北京)电子信息产业有限公司 | PCB and wiring method thereof |
| CN105578714A (en) * | 2015-12-11 | 2016-05-11 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | Novel lamination structure of multilayer high-speed PCB and signal via-hole optimization method |
| CN106406531A (en) * | 2016-09-20 | 2017-02-15 | 常州奥施特信息科技有限公司 | A method for VR virtual printed circuit board manufacture factory |
| CN107182167A (en) * | 2016-03-10 | 2017-09-19 | 无锡深南电路有限公司 | Thick copper PCB power panels |
| CN108112168A (en) * | 2018-01-25 | 2018-06-01 | 郑州云海信息技术有限公司 | A kind of thickness copper coin internal layer non-functional pad design adding method |
| CN108303639A (en) * | 2018-04-10 | 2018-07-20 | 生益电子股份有限公司 | It is a kind of to carry on the back the aptitude tests module and aptitude tests method for being bored into line |
| CN108495514A (en) * | 2018-03-07 | 2018-09-04 | 中国船舶重工集团公司第七二三研究所 | A kind of compression joint type connector pore model processing method |
| CN112020214A (en) * | 2020-09-01 | 2020-12-01 | 北京子兆信息技术有限公司 | Multilayer high-frequency PCB and signal via hole optimization method thereof |
| CN112464313A (en) * | 2020-11-30 | 2021-03-09 | 苏州浪潮智能科技有限公司 | Method for processing differential routing through hole of server wiring |
| CN112888155A (en) * | 2021-01-14 | 2021-06-01 | 合肥移瑞通信技术有限公司 | Circuit board, circuit board via hole optimization method, electronic device and storage medium |
| WO2022089155A1 (en) * | 2020-10-27 | 2022-05-05 | 南京中兴软件有限责任公司 | Printed circuit board and manufacturing method therefor |
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| CN1756460A (en) * | 2004-09-30 | 2006-04-05 | 华为技术有限公司 | High-density BGA printed circuit board wiring method |
| CN1664823A (en) * | 2005-03-30 | 2005-09-07 | 中国人民解放军国防科学技术大学 | Pseudo ring-free aperture passing method |
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|---|---|---|---|---|
| CN103995941B (en) * | 2014-06-06 | 2017-08-25 | 无锡市同步电子科技有限公司 | A kind of isolation method to set up of High-speed Board Design mesopore impedance matching |
| CN103995941A (en) * | 2014-06-06 | 2014-08-20 | 无锡市同步电子科技有限公司 | Isolating setting method of pore impedance matching in high-speed circuit design |
| CN104023474A (en) * | 2014-06-24 | 2014-09-03 | 浪潮电子信息产业股份有限公司 | Method for alleviating influence of impedance mutation on signal transmission line quality |
| CN104202905A (en) * | 2014-09-28 | 2014-12-10 | 浪潮(北京)电子信息产业有限公司 | PCB and wiring method thereof |
| CN105578714A (en) * | 2015-12-11 | 2016-05-11 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | Novel lamination structure of multilayer high-speed PCB and signal via-hole optimization method |
| CN107182167A (en) * | 2016-03-10 | 2017-09-19 | 无锡深南电路有限公司 | Thick copper PCB power panels |
| CN106406531A (en) * | 2016-09-20 | 2017-02-15 | 常州奥施特信息科技有限公司 | A method for VR virtual printed circuit board manufacture factory |
| CN108112168A (en) * | 2018-01-25 | 2018-06-01 | 郑州云海信息技术有限公司 | A kind of thickness copper coin internal layer non-functional pad design adding method |
| CN108495514A (en) * | 2018-03-07 | 2018-09-04 | 中国船舶重工集团公司第七二三研究所 | A kind of compression joint type connector pore model processing method |
| CN108303639A (en) * | 2018-04-10 | 2018-07-20 | 生益电子股份有限公司 | It is a kind of to carry on the back the aptitude tests module and aptitude tests method for being bored into line |
| CN112020214A (en) * | 2020-09-01 | 2020-12-01 | 北京子兆信息技术有限公司 | Multilayer high-frequency PCB and signal via hole optimization method thereof |
| CN112020214B (en) * | 2020-09-01 | 2022-07-19 | 北京子兆信息技术有限公司 | Multilayer high-frequency PCB and signal via hole optimization method thereof |
| WO2022089155A1 (en) * | 2020-10-27 | 2022-05-05 | 南京中兴软件有限责任公司 | Printed circuit board and manufacturing method therefor |
| CN112464313A (en) * | 2020-11-30 | 2021-03-09 | 苏州浪潮智能科技有限公司 | Method for processing differential routing through hole of server wiring |
| CN112464313B (en) * | 2020-11-30 | 2022-06-03 | 苏州浪潮智能科技有限公司 | Method for processing differential routing through hole of server wiring |
| CN112888155A (en) * | 2021-01-14 | 2021-06-01 | 合肥移瑞通信技术有限公司 | Circuit board, circuit board via hole optimization method, electronic device and storage medium |
| CN114614247A (en) * | 2022-03-16 | 2022-06-10 | 南京吉凯微波技术有限公司 | Integrated network of millimeter wave tile-type phased array antenna |
| CN115455886A (en) * | 2022-08-05 | 2022-12-09 | 上海移柯通信技术股份有限公司 | PCB design method, PCB, electronic device, storage medium and terminal |
| CN115455886B (en) * | 2022-08-05 | 2023-04-11 | 上海移柯通信技术股份有限公司 | PCB design method, PCB, electronic device, storage medium and terminal |
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