Beijign Diamond Design Center---PCB copy board, PCB design
Product Details:

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Address:Suite906, TowerA, HanrongBuilding, NO.50ZhichunRD,
5. PCB layout
o 5.1 Circuit s egregation
5.1.1 The boundary between outside- and inside-worlds
5.1.2 Boundaries within an inside-world
5.1.3 Segregation
5.1.4 Component placement and routing of tracks
o 5.2 Interface Suppression
5.2.1 Suppressing outside/inside-world interfaces
5.2.2 Interfaces between dirty/high speed/noisy and clean/sensitive/quiet areas
5.2.3 Details of interface suppression techniques
o 5.3 Reference planes
5.3.1 Creating proper reference planes
5.3.2 Connecting 0V planes to chassis Cooperation mode

Home > ODM/OEM > Cooperation mode

Why should you chose ODM/OEM mode, other than develop by yourself

As an embedded engineer, you frequently have to complete project development in short time, this situaiton usually make you under pressure. Beside, you have to seek the balance point among project specification, prototype design and the quality and cost of finished prototype. As to your dilemma, the OEM/ODM mode may be an good solution. Let start our analysis in terms of the facts as follows:

a. Risk of development

b. Cost of development

c. Time to market

a. Risk of development

a) The detailed function request, for example: which kind of screen they need, which kind of periphery connection it has.

b) Performance requirement

c) Time request

d) Quantitative requirement

e) The cost request

b. Emdoor provides the project plan of proposal according to the customer request ,including

f) Whole realization plan of system

g) Component type

h) Performance index

i) Tests way

j) Project cycle

k) The project expense and payment method

c. Modify the project plan of proposal according to the feedback of customer

d. Indeed project start

e. Update project process timely.

f. Submit project resources and the test approval according to the contract requirement

Submit resources

a. Complete hardware design documents(including schematic diagram and PCB chart)

b. Complete software source code

c. Instruction documents of project

d. Production document

e. Project hands over and technical training

The characteristic

a. Customer can complete project development with lower cost

b. Train own engineer group per this project, complete next project promotion and new product development with obtained software and hardware resources.

2. OEM

Flow

a. Chooses appropriate hardware integration module of end product that Emdoor provided

b. Develop related daughter board per their own product demand with Emdoor technical support personnel help in order to use with module that Emdoor provided together.

c. Complete the development software of application level based on Emdoor development tool bag.

d. Present product

Provide resources

a. Extremely quick speed of product promotes.

b. Avoid potential risk during the developing process because of selecting the ready-made software and hardware core module.

c. Work load of maintaining of last period in small.

3. ODM+OEM mode

Flow

a. Customer provides the demand of detailed software and hardware.

b. Emdoor chooses appropriate software and hardware integration module of end product per customer??
8￥?
s demand

c. Emdoor makes appropriate connection board per customer demand

d. Emdoor makes appropriate software per customer demand

e. Test

f. Present product

Provide resources

a. Software and hardware integration module of end product

b. Use documents of software and hardware

c. Complete hardware design documents of daughter board ( including schematic diagram and PCB chart)

d. Complete software source code of daughter board

e. Technical service, training and support.

Detailed flow can be adjusted properly again according to the customer request.

5.3.3 Shielding effect of planes
5.3.4 Interconnecting planes in multi-PCB assemblies
5.3.5 To split or not to split
5.3.6 Galvanically isolated planes
5.3.7 What if multilayer PCBs are thought too costly
o 5.4 Power decoupling
5.4.1 Power decoupling techniques
5.4.2 Self-resonance problems
5.4.3 Decoupling without power planes
o 5.5 Transmission Lines
5.5.1 Manufacturing issues with transmission lines
5.5.2 Terminating transmission lines
o 5.6 Layer "stack up"
o 5.7 Useful references

The inside/outside-world interface components are restricted to one dedicated edge of the PCB to encourage all unwanted external currents (e.g. caused by voltage differences in protective earths) to restrict themselves to that area of the PCB, and discourage them from flowing through circuit areas.

Where an effective enclosure shield exists, the inside/outside-world boundary becomes the shielded wall of the enclosure. All of the associated filtering and suppression components, and cable screen bonding, must then use a connector panel set in the wall of the enclosure as their reference (as described in Part 4). A single area for all interconnections is still best. A wider range of PCB-mounted screened and/or filtered connectors that can also bond to a metal panel is now available. These parts would be soldered to the PCB reference plane, then electrically bonded metal-to-metal to the wall of a screened enclosure during final assembly, and can be very cost-effective.

Narrow channels free from components should be left between each of the segregated circuit areas on the PCB. These should be wide enough for the fitting of a PCB-mounted "tuner-can" shield, and provision should be made (at least on prototype boards) for bonding such screening cans to the 0V plane at frequent intervals (say, every 15mm) along all edges.

5.1.4 Component placement and routing of tracks

The most noisy or susceptible components in each area should be positioned first, as close to the centre of their areas and as far away from cables or wires as possible. Such components include clock generators and distribution (extremely noisy); bussed digital ICs (very noisy); microcontrollers (noisy); switch-mode power transistors and rectifiers and their chokes, transformers, and heatsinks (all very noisy), analogue ICs (sensitive), and millivolt level amplifiers (very sensitive). Remember (from Part 1) that even low-frequency operational amplifiers can be extremely susceptible to interference, even beyond 1GHz.

After the extremely short connections from components to reference planes, digital clock distributions (very aggressive signals) must be the next "nets" to be routed, and must be run on a single PCB layer adjacent to a 0V plane.

These tracks must be as short as possible, and even so may need to use transmission-line techniques (described later). It may be necessary to experiment with component placement to achieve minimum track lengths.

Where clock tracks are made longer than necessary to minimise skew, a "serpentine" layout is best.

Digital busses and high-speed I/O should be routed next, in a similar manner to clock tracks, deferring only to clock tracks and plane bonds where there is a conflict. Very susceptible tracks, such as those carrying millivolt transducer signals, should also be routed as if they were clock or data buss tracks, although they will always be in a different segregated area of the PCB. The later section on transmission lines describes what to do where critical tracks have to change layers.

All other types of analogue, digital, and power signals should also be routed according to how aggressive or sensitive they are. Where these characteristics are not obvious from a circuit analysis, probing a prototype with a wide-band oscilloscope (and/or spectrum analyser) with voltage or current probes will reveal which are the most aggressive, and injecting voltages or currents from a wideband sweep generator will reveal which are most sensitive. A loop probe can be most useful here, being able to inject signals into tracks without requiring connection of external equipment to potentially sensitive area of the circuit concerned.

All components and their tracks must be contained within their designated PCB areas. The only tracks to exit or enter an area are those that have to connect to other areas. If it has not proved possible to eliminate all the wires and cables inside a product, make sure that their routes are fixed so they can't stray into the wrong PCB areas.

It is best to check that segregation instructions have been followed on draft PCB layouts, well before PCB manufacture. An easy check is to count the tracks and other conductors which cross the dotted lines showing the segregated areas on the circuit diagram - there should be exactly the same number crossing the channels between areas on the draft PCB layout. Where PCBs have been autorouted it is usual to find additional tracks crossing area boundaries - these are often the source of much design heartache, so eliminate them right away by applying more skill to the track layout.

Autorouting does not generally provide good layouts for EMC purposes. Minimize Noise in Audio Channels with Smart PCB Layout

Abstract: This application note discusses several factors that affect audio functionality in a cell-phone PCB design. The article shows examples of a problematic and a well-designed PCB for a cell phone. The differences between the two layouts are discussed, with emphasis given to design considerations that improve audio function.

Introduction
For PCB layout engineers, cell phones provide the ultimate challenge. Each subsystem has conflicting requirements, and modern cell phones include nearly every subsystem found in a portable device. A well-designed PCB must both maximize the performance of each device connected to it and prevent the various subsystems from interfering with each other. Inevitably, the conflicting requirements of each subsystem result in some compromise. Finally, although audio functionality in cell phones is increasing, the audio circuitry is often given the least consideration during PCB design.

Component Placement
The first step of any PCB design is choosing where to place the components. This task is called "floor planning." Careful component placement can ease signal routing and ground partitioning. It minimizes noise pickup and the board area required.

Cell phones contain a mixture of digital and analog circuitry that must be separated to prevent noise from the digital portion from interfering with the sensitive analog circuits. Partitioning the PCB into a digital and an analog region simplifies the separation task.

The RF section of a cell phone is typically considered analog. Yet there is a common problem in many cell-phone designs where noise coupled from the RF section into the audio circuitry is demodulated into audible noise. To prevent this, the RF and audio sections should be separated as much as possible.

Once the PCB has been partitioned into analog, digital, and RF sections, the component placement within the analog section must be selected. Components should be placed to minimize the distance that audio signals travel. Locate the audio amplifier as close to the headphone jack and loudspeaker as possible. This positioning will minimize EMI radiation from Class D speaker amplifiers, and minimize the noise susceptibility of low-amplitude headphone signals. Place the devices supplying the analog audio as close to the amplifier as possible to minimize noise pickup on the amplifier inputs. All input signal traces will act as antennas to RF signals, but shortening the traces helps reduce the antenna efficiency for frequencies typically of concern.

Example Component Placement
Figure 1 shows an example of poor audio component placement. The most serious problem is that the audio amplifier is placed quite far from the audio sources. This distance increases the chances of noise coupling because the traces are more prone to pass near noisy digital circuitry. The long traces can also be efficient RF antennas. In cell phones using GSM technology, these antennas can pick up the GSM transmission and feed the signal into the audio amplifier. Nearly all amplifiers will demodulate the 217Hz envelope to some degree and generate unwanted noise on the output. In the worst case, this process causes noise on the output that completely overwhelms the desired audio signal. Minimizing input trace lengths thus prevents the signal from ever reaching the amplifier.

There is another problem with the component placement in Figure 1: the amplifier is not placed near the speaker and the headphone jack. If the speaker amplifier is Class D, then the long speaker traces increase the EMI radiation from the amplifier. This radiation could potentially prevent the device from passing government-mandated testing. The long headphone and speaker output traces both increase the trace resistance, thus decreasing the power delivered to the load.

Finally, since the components are so spread apart, the traces connecting the components will be routed near other subsystems in the phone. Not only does this distance increase the difficulty of routing the traces, but it also increases the difficulty of laying out other parts of the phone.

Figure 1. Example of poor component placement in a cell phone.

Figure 2 shows the same components as Figure 1, but rearranged to use the space more effectively and to minimize trace lengths. Notice how all the audio circuitry has been partitioned to be near the headphone jack and the speaker. The audio input and output traces are much shorter and the nonaudio circuitry has been moved to a different part of the PCB. This design will have lower overall system noise, be less susceptible to RF interference, and be easier to layout.

Figure 2. Example of good component placement in a cell phone.

Signal Routing
When considering noise and distortion on the audio output, signal routing typically has limited impact. There are, nonetheless, some steps to ensure that performance is not compromised.

Loudspeaker amplifiers typically are powered directly from the main system voltage and require relatively high current. Resistance in the trace will result in voltage drops that reduce the supply voltage of the amplifier and waste power in the system. The trace resistance also causes the normal fluctuations in supply current to convert to fluctuations in voltage. To maximize performance, use short wide traces for all amplifier power supplies.

Differential signaling is an advantage that should be exploited whenever possible. Differential inputs provide noise immunity by rejecting any signal that is common to the positive and negative signal lines. There are several considerations to ensure that the differential amplifier is effective. Specifically, it is important that the differential signal pairs have the same length and the same impedance. The signal pairs should be routed as close to each other as possible to ensure that they pick up the same noise. Differential inputs on amplifiers are particularly effective in reducing noise from the digital circuits in the system.

Grounding
Grounding plays the single, most significant role in determining whether the device's potential is achieved by the system. A poorly grounded system will likely have high distortion, noise, crosstalk, and RF susceptibility. Although one can question how much time should be devoted to system grounding, a carefully designed grounding scheme prevents a large number of problems from ever occurring.

The ground in any system must serve two purposes. First, it is the return path for all currents flowing to a device. Second, it is the reference voltage for both digital and analog circuits. Grounding would be a simple exercise if the voltage at all points of the ground could be the same. In reality, this is not possible. All wires and traces have a finite resistance. This means that whenever there is current flowing through the ground, there will be a corresponding voltage drop. Any loop of wire also forms an inductor. This means that whenever current flows from the battery to a load, and back to the battery, the current path has some inductance. The inductance increases the ground impedance at high frequencies.

While designing the best ground system for a particular application is no simple task, some general guidelines do apply to all systems.
Establish a Continuous Ground Plane for Digital Circuits
Digital current in the ground plane tends to follow the same route that the original signal took. This path creates the smallest loop area for the current, thus minimizing antenna effects and inductance. The best way to ensure that all digital signal traces have a corresponding ground path is to establish a continuous ground plane on the layer immediately adjacent to the signal layer. This layer should cover the same area as the digital signal trace and have as few interruptions in its continuity as possible. All interruptions in the ground plane, including vias, cause the ground current to flow in a larger loop than is ideal, thereby increasing radiation and noise.
Keep Ground Currents Separate
The ground currents for digital and analog circuits must be separated to prevent digital currents from adding noise to the analog circuits. The best way to accomplish this is through correct component placement. If all the analog and digital circuits are placed on separate parts of the PCB , the ground currents will naturally be isolated. For this to work well, the analog section must contain only analog circuits on all layers of the PCB.
Use the Star Grounding Technique for Analog Circuits
Star grounding uses a single point on the PCB as the official ground point. This point, and only this point, can be considered to be at ground potential. In a cell phone the battery ground terminal is a logical choice for the star point. Do not think of currents as flowing into the ground plane and disappearing; rather consider all ground currents as flowing back to this ground point.

Audio power amplifiers tend to draw relatively large currents that can adversely affect both their own and other ground references in the system. To prevent this problem, provide dedicated return paths for bridged-amplifier power grounds and headphone-jack ground returns. Isolation allows these currents to flow back to the battery without affecting the voltage of other parts of the ground plane. Remember that these dedicated return paths should not be routed under digital signal traces because they could block the digital return currents.
Maximize the Effectiveness of Bypass Capacitors
Nearly all devices require bypass capacitors to provide instantaneous current. To minimize the inductance between the capacitor and the device supply pin, locate these capacitors as close as possible to the supply pin which they are bypassing. Any inductance reduces the effectiveness of the bypass capacitor. Similarly, the capacitor must be provided a low-impedance connection to ground to minimize the capacitor's high-frequency impedance. Directly connect the ground side of the capacitor to the ground plane, rather than routing it through a trace.
Flood All Unused PCB Area with Ground
Whenever two pieces of copper run near each other, a small capacitive coupling is formed between them. By running ground flood near signal traces, unwanted high-frequency energy in the signal lines can be shunted to ground through the capacitive coupling.
Example Grounding
Figure 3 shows an example of a well-grounded system. Note, first, that the PCB is partitioned into a digital section at the bottom and an analog section at the top. The only signals crossing the partition boundary are I2C control signals, and these have a direct return path following the signal trace. This layout ensures that digital signals will remain in the digital section of the board and that no digital ground currents will be blocked by the splits in the ground plane. Also note that most of the ground plane is uninterrupted. Even in the digital section where there are interruptions, they are far enough apart to allow currents to flow freely.

For this example the star point is in the upper left corner of the PCB. The breaks in the analog portion of the ground plane allow the Class D and charge-pump currents to return to the star point without interfering with the general analog ground plane. Also note that the headphone jack has a dedicated trace returning the headphone ground current to the star point.

Figure 3. Example of a silkscreen and ground layer of a well-grounded design.

Conclusion
Although creating a well-designed PCB can be time-consuming and challenging, the investment is well worth the time spent. The end result is a system with less noise, higher immunity to RF signals, and less distortion. The PCB will also have better EMI performance and may require less shielding.

Ultimately, if the PCB is not carefully designed, preventable problems will be discovered when the product is in test. These problems are much more difficult to fix once the layout is complete, and often demand significant time to correct. All too often the fixes require additional components that add to the total system cost and complexity.

An abbreviated version of this application note appeared in the July 16, 2007 issue of EE Times, a CMP publication.Advanced PCB design and layout for EMC. Part 1

part1

Advanced PCB design and layout for EMC. Part 1 ??
8§C Saving time and cost overall
By Eur Ing Keith Armstrong C.Eng MIEE MIEEE, Cherry Clough Consultants
This is the first in a series of eight articles on good-practice EMC design techniques for printed circuit board (PCB) design and layout. This series is intended for the designers of any electronic circuits that are to be constructed on PCBs, and of course for the PCB designers themselves. All applications areas are covered, from household appliances, commercial and industrial equipment, through automotive to aerospace and military.

These PCB techniques are helpful when it is desired to-

Save cost by reducing (or eliminating) enclosure-level shielding
Reduce time to market and compliance costs by reducing the number of design iterations
Improve the range of co-located wireless datacomms (GSM, DECT, Bluetooth, IEEE 802.11, etc.)
Use very high-speed devices, or high power digital signal processing (DSP)
Use the latest IC technologies (130nm or 90nm processes, chip scale??
8￥?
packages, etc.)
The topics to be covered in this series are:

Saving time and cost overall
Segregation and interface suppression
PCB-chassis bonding
Reference planes for 0V and power
3.2 Shrinking packaging
3.3 Shrinking supply voltages
3.4 PCBs are becoming as important as hardware and software
3.5 EMC testing trends
4 Designing to reduce project risk
4.1 Guidelines, maths formulae, and field solvers
4.2 Virtual design
4.3 Experimental verification
5 References

1 Reasons for using these EMC techniques
Most professional circuit and PCB designers would love to employ all of the good EMC techniques described in [1] - [4] and this series, but are often prevented from doing so by project managers and other managers who only see these techniques as wasted time and added cost.

Sometimes it is the manager of the PCB layout department who prevents the use of good EMC techniques, usually claiming that the product cost-to-make will increase, but often really because they have become familiar with their existing PCB design rules and bare-board manufacturers and don??
8￥?
t want to make the effort to change.

This section will show that such management approaches are completely the opposite of what is really required these days for success in the design and manufacture of electronic products of any type, in any volume.

PCBs have continually been getting more high-tech and costly ever since they were first invented, and they will continue along this path for ever. In a few years time microvia PCBs with more than 8 layers and embedded capacitance will be the norm. It is a tough commercial world for everyone these days, and companies that don??
8￥?
t keep up with PCB technology will be left in the dust of those that do.

1.1 Development ??
8§C reducing costs and getting to market on time
Even if a PCB has no nearby wireless datacommunications antennas, and even if it does not use high-speed devices or signals, these PCB techniques can save time and money by reducing the number of iterations it takes to get the circuit working with its full performance specification. This is because many EMC techniques are also signal integrity techniques. In fact, good PCB design for EMC goes beyond the requirements for signal integrity; so a PCB that is designed using good EMC techniques generally has excellent signal integrity.

The author originally developed the PCB design techniques described in [1] - [4] over ten years and three companies in the 1980s to enable powerful digital processing, sensitive high-specification analogue circuits, and switch-mode power converters to share the same enclosure, even the same PCB, without compromising the analogue performance at all. Projects that used to require 10 or more design iterations could use these techniques to meet their performance specifications on the first PCB prototype. During the 1990s it was found that these techniques also achieved excellent compliance with EMC Directive test standards, without requiring high-specification enclosure shielding, sometimes without any shielding at all.

Good EMC design techniques are good signal integrity techniques, for both analogue and digital circuits. This means more predictable project timescales with fewer three-cornered arguments between the circuit, PCB and software designers as to whose fault it is that the performance falls short of its specification.

However, there are still very many companies that do not employ the techniques described in [1] - [4], never mind the advanced PCB techniques described here. This appears to be because they don??
8￥?
t realise that the true cost of a design modification increases rapidly as a project progresses. People only tend to see the obvious costs of the modification (the hours spent, the cost of another prototype PCB, etc.) which are the same whatever stage the project is at, but Figure 1A gives an idea of how the real cost of a modification varies during the project timescale.

Of course, once a design iteration causes a delay in the market introduction the true costs of that modification can be astronomical. This issue is much more important than it was even ten years ago, due to the very short product lifetimes now being experienced for almost every application area. Some cellphone and computer industries already have product lifetimes of 90 days or less, but it is increasingly likely that for even quite ordinary products and equipment, being 6 months late to market can mean no market at all ??
8§C with the consequent loss of all the investment in the project. For some debt-financed companies, the loss of investor confidence caused by a late market introduction can lead to the loss of the company.

So it is not too exaggerated a claim to say that good PCB design and layout techniques are a valuable financial tool and competitive weapon. The section below on trends??
8￥?
should make this claim even more clear.

1.2 Reducing unit manufacturing costs
1.1 above dealt with project costs, but unit manufacturing costs also benefit from the use of good EMC techniques at the level of PCB design and layout.

A general rule of thumb is that the true costs, in manufacture, of controlling EMC increases tenfold for each higher level of assembly. So the lowest-cost place to control EMC is in the design of the ICs and semiconductors. Achieving the same EMC performance at PCB level costs about ten times more than if it could be done in the IC. And if implemented at product enclosure level the true costs of achieving the same EMC performance are ten times higher again, as shown by figure 1B.

Few designers have as much control over the EMC characteristics of their ICs as they would like. Most are stuck with using commodity ICs with no EMC controls at all (in fact, some of them seem to have been designed to maximise EMC problems). FPGA designers, and especially ASIC designers, have a greater degree of control of the EMC characteristics of their devices ??
8§C but even so there are limits to what current technology can achieve.

However, as subsequent parts of this series will show, it is possible to completely control all aspects of EMC (except for direct lightning strike) at the level of the PCB, the lowest-possible-cost solution after IC design techniques.

A common project management perception in too many companies is the idea that the product made with the lowest-cost components will be the most profitable. So designers are constrained to achieving the lowest possible BOM cost??
8￥?
(BOM = Bill Of Materials) for their circuits and PCBs, which means that numerous good EMC design techniques (such as PCBs with at least 8 layers) are not permitted because the designers cannot prove that they are essential. (This was the very management technique that led directly to the demise of the Challenger space shuttle, because the engineers could not prove to their managers that the booster O-ring seals would malfunction at the low temperatures present at the launch site).

This management philosophy leads to the idea that EMC measures are best bolted on??
8￥?
at the end of a project, once it is known what is really required. But these EMC measures will have a unit manufacturing cost of around 10 times what they would have cost if implemented at PCB level (see figure 1B). And since almost all modern circuits of all types now suffer from EMC problems, whether emissions or immunity (and all future ones will, see later) the typical result of the lowest-possible BOM cost??
8￥?
approach is that the unit manufacturing costs of the products are actually increased by considerably more than they need be.

Also, implementing EMC measures near the end of a project suffers greatly from the very high cost of modifications at this stage, see 1.1 and figure 1A, and it is not at all unusual for market introduction to be delayed by one or more months due to problems with achieving EMC compliance. Late market introduction is a very serious commercial and financial issue these days, much more so than it was even 10 years ago.

This article is not the place to discuss product costing issues. But it is worth mentioning here that, except for a very few types of products (high-performance PC motherboards and graphics cards, some specialist instruments, etc.), the profitable selling price of a product bears no relationship at all to the total cost of its components. Apart from some special application areas, anyone who thinks there is a direct relationship between a product??
8￥?
s BOM cost and its selling price really needs to understand his or her business a lot better.

It is not at all an exaggerated claim to say that although using good EMC techniques in PCB design and layout usually increases the BOM cost for the PCB assemblies in a product, the unit manufacturing cost will usually be reduced, making more profitable products. The section below on trends

1.3 Enabling wireless datacommunications
Company: [TW] Feng Cheih Precision Machinery Corporation
Product: hydraulic machine, shoe-making machinery, conveyor, hyeraulic foam moulding machine, rubber machine, hydraulic cutting machine, SMC moulding machine, PCB multi-layer laminating machine, shoes, material, oil packing, oil seal, melamin foam machine, c

4.
Company: [TW]Tairuey Electrical Industry Co.,Ltd.
Product: OEM, OEM for PCB board, Assembly for PCB

5.
Company: [TW]Ho Chiang Co., Ltd.
Product: CNC, PCBASE, DSP, NC, CONTROLLER

6.
Company: [TW]Kingley Technology Co., Ltd.
Product: membrane switches, keypad assemblages, electro luminescence, single-sided PCBs, metal dome, mylar dome, panels and membrane circuits of biochips, FPC

7.
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Product: Computer Cable, Din & Mini Din Cable, USB Series(Universe Serial Bus), Extension Cable, Joystick Cable, Special Design Cable, Coaxial & Ethernet & Wiring Harn

8.
Company: [TW]GetSweet Incorporation
Product: PCB, pcb, pcbs

9.
Company: [TW]Shang Yu Electronics Co., Ltd.
Product: electronical products, PCB program designing, mechanical automatic control, light remote contrller, electronical water level controller

10.
Company: [IN]Vin Electronics
Product: pcb, pcba, component, solder, prototype, ems, box assembling, final inspection, led, rohs, pcb design, pcb fabication, production, electronic, electrical, pcb manufacturing, pcb assembling, export, import, computer

11.
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Product: ks, kst, terminals, connectors, electrical terminals, lighting system, fine ceramic, titanium, insulated copper terminals, quick disconnectors, cord end, wiring accessory, butt splice, tools, cable tie, pc cables, injections parts, stamping parts,ba

12.
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Product: connectors,wiring terminal,housing inlet,wafers,plug,socket,cord-end nut,Harnesses parts,cable assembly

13.
Company: []Jyi Ta Fu International Co., Ltd.
Product: PCBs, Jyi Ta Fu International Co., Ltd. located in Taipei Taiwan. We are specializing in multilayer 2-16 PCBs Manufacture. According your enquiries! Our major products: Service: Single, Double Sided, Multilayer, Flex.-Rigid CBs Number of layers: 2-1

14.
Company: [CN]Success Circuits International Co., Ltd
Product: PCB, PCBA, FPCB

16.
Company: [CN]Shenzhen Grande Electronic Co., Ltd.
Product: PCB, Single PCB, Double-sided PCB, Muti PCB, PCBA, MP4&Game Player, IP Camera

17.
Company: [KR]PK Diamond Inc.
Product: diamond saw blades/diamond wire saw/router bits/diamond segments/grinding cup wheels/polishing pads/polishing drums/diamond & cbn wheels/turbo rim blades/tuckpoint blades/ring saw blades/pcd pcbn inserts/endmills/reamers/cvd/dicing blades/micro b

18.
Company: [TW]Farman Machinery Industry Co., Ltd.
Product: CNC TOOL GRINDING MACHINE,TRUEING & DRESSING MACHINE,PCD & PCBN TOOL GRINDING MACHINE,CUTTER GRINDER,UNIVERSAL DRILL GRINDER

19.
Company: [TW]Zun Full Internation Co.,Ltd
Product: SAMPLE, PCB MP, PCBA, REAPIR

20.
Company: [IN]PCBindia.com
Product: Adaptors Audio Battery, Cables Circuit Breakers, Capacitor, Coils Crystals Fans, Filters ICs Lamps, Magnets Motors Rectifiers, Relays Resistor Sensors, Switches Transducers Varistor
computer hardware manufacturer is looking for talented professional to fill the following positions for our Shenzhen branch office:

(1) Electronic Engineer/Senior Electronic Engineer

Requirement
* Bachelor degree in electronics engineering
* 3 years experience in hardware development, preferably in the field of computer hardware/networking device
* Good understanding of digital circuit design and use of components
* In-depth skills in schematic capture, PCB layout and soldering
* Excellent troubleshooting and demonstrated problem solving skills
* Good command of English is a must
* Experience in IC layout and simulation tools is an added advantage
* RTOS and embedded Linux know-how is preferable
* Candidate with higher qualification will be offered the post of senior electronic engineer

Job description
* Work closely with product managers in development of PC hardware
* Participate in digital IC layout design and simulation projects
Nanometer design challenges
On-chip debug
Power estimation
Substrate modeling
Signal integrity, crosstalk
Structured ASICs and FPGAs
Yield analysis & reliability
3. Low-Power Design
Sample topics
EMI & resonance effects
Leakage power control
Low-power chip design
Noise characterization & containment
Power budgets
4. Chip and Package Co-Design
Sample topics
Buffer modeling
Ceramic vs. organic
Chip/package/board co-design
EMI shielding
High-speed signaling
Merging of chip design & package design
Package modeling & measurement
Power management
System-in-package (SiP vs. SoC)
Thermal management
Timing closure
5. PCB and Package Technologies
Sample topics
Advanced materials
Backdrilling methods and effects
Embedded passives
Fabrication: cost vs. performance
Halogen-free materials
Impact of lead-free materials & processes
Manufacturing impact on electrical properties
Materials modeling (non-homogeneous)
Microvias, RF vias & thermal vias
Power delivery
6. Chip and Board Interconnect Design
Sample topics
Characterization, compliance testing
Electrostatic discharge (ESD) protection
High-speed I/O interoperability
High-speed serial design
Integrated optical links
Loss & timing budgets
Physical modeling & simulation
SerDes design techniques
System interconnect architecture
7. High-Speed Cable Interconnect Design
Sample topics
Differential systems
Single-ended systems
ESD & EMC management
Interconnect signal conditioning
Modeling & measuring techniques
Signal/power integrity for interconnects
T-line behavior simulation & analysis
Transmission media & characterization
Waveform measurement uncertainty
8. High-Performance Backplane Interconnect Design
Sample topics
Backplane interconnect
Backplane signal conditioning
Backplane upgrades
Loss & timing budgets