In the PCB layout, designers will consider different situations and use different design tools. The main factors to consider are:
User interface (UI)
Large component library
The printed circuit board design is based on the circuit schematic diagram to realize the functions required by the circuit designer. The online PCB design mainly refers to layout design, which needs to consider various factors such as the layout of external connections, the optimal layout of internal electronic components, the optimal layout of metal wiring and through holes, electromagnetic protection, heat dissipation, and so on. Excellent layout design can save production costs and achieve good circuit performance and heat dissipation performance. Simple layout design can be implemented manually, and complex layout design needs to be implemented with the aid of computer-aided design (CAD).
An automated software program establishes a convenient method in PCB design that can be easily converted to a physical PCB. Listed below are some popular design tools such as Altium Designer, Eagle, and OrCAD.
Altium Designer is more commonly used in China. This software is relatively simple and the design is more casual. It is not very good to use this software for complex PCBs.
Cadence SPB, the ORCAD schematic design is an international standard; PCB design and simulation are very complete, which is more complicated to use than protel, mainly because the requirements and settings are complicated; Protel is obviously powerful.
Mentor. The current MentorEE version is Mentor EE 7.9. It belongs to the same level of PCB design software as Cadence SPB. It is inferior to cadence SPB in some places. Its strengths are pulling wire and flying wire. It is called a flying wire king.
EAGLE Layout This is the most widely used PCB design software in Europe.
The PCB online design software mentioned above is used a lot, and Cadence SPB and MentorEE are well-deserved kings.
Zuken's CADSTAR PCB design software provides a complete design environment. CADSTAR provides design capabilities throughout the PCB design process, from schematic to layout, routing, signal integrity simulation, power integrity analysis, and 3D mechanical integration.
SPEEDAPCB's senior designers with rich design experience will provide one-to-one PCB design service for you, we can handle many different kinds of PCB circuit design, including high-frequency PCB design. And we will strive to satisfy customers. Reduce the number of R & D and the costs for you.
Design delivery period and capability
|Quantity||Delivery Time(working day)|
|The highest layer of HDI||20 layers|
|Highest level HDI||HDI any level of 24|
|The highest layer of design||52 layers|
|Min line width||2.5mil|
|Min line spacing||2.5mil|
|Min hole size||6mil（4mil laser drilling）|
|Min BGA spacing||0.35mm|
|Highest speed signal||28GBPS|
PCB Design Process
PCB Design Tools
There are many PCB design software, including Cadence, Altium Designer, PADS and so on. Currently the most commonly used is Altium Designer. Interface is relatively easy to get started, more scientific, in addition to gerber generation and netlist import is also more user-friendly, is generally preferred.
The choice of components in inverter PCB Design
The same chip resistor, there may be different packages, you need to pay attention to his package when choosing a resistor, in general, the larger the package, the greater the power rating, the higher the withstand voltage, however, the more space occupied. So you need to choose carefully in inverter PCB design. In addition, there are different types of chip resistors, such as thick film, wire wound, thin film, metal film, etc., the former is the most common, for most applications is also sufficient, but usually large parasitic parameters, wire wound is usually high-power resistors, 2W-10W, etc., parasitic sense is very large. The latter two are generally not large power, but the parasitic parameters are small.
The choice of alignment width in inverter PCB design
Alignment can not be too narrow. It is very easy to understand that the same thickness of copper, the greater the width, parasitic resistance, the smaller the inductance, at the same time, the greater the rated current. But it is not that the wider the better, for the signal, too wide instead of easy and other lines coupled, which leads to the introduction of EMI noise.
The decoupling capacitor is very important in inverter PCB design, usually added to the power supply side, usually used to regulate the voltage, filter out the current ripple, increase the output stability. For example, between the positive and negative pins of the op-amp power supply, a few microfarads of capacitance should be added. The decoupling capacitor needs to be as close to the chip as possible, and the decoupling capacitor should be selected with a small ESL, such as MLCC. We generally use more than one decoupling capacitor in inverter PCB design, for example, 4.7uF + 0.1 uF + 10 nF combination, used for different frequency band noise. Because the high frequency noise corresponds to a small decoupling capacitor, so we need to paste the 10 nF closer and place the 4.7 uF at the far end, which can effectively reduce the noise interference for the chip.
The driver board needs to be as close as possible to the semiconductor power devices in the whole inverter PCB design, such as IGBTs, MOSFETs, etc. The reason is that long distance loops can cause large parasitic parameters and therefore introduce large gate-level oscillations, which eventually lead to straight-through problems. It is best to use the Kelvin connection method in inverter PCB design, which is to distinguish the source of the power from the source of the drive loop.
This step according to the board has been determined the plane size and each mechanical positioning, in the inverter PCB design environment to draw the PCB board surface, and according to the positioning requirements of the required connectors, keys / switches, digital tubes, indicators, inputs, outputs, screw holes, assembly holes, etc.. And fully consider and determine the wiring area and non-wiring area (such as how much around the screw hole belongs to the non-wiring area).
Special attention needs to be paid to the placement of components in inverter PCB design, we must consider the actual size of the components (the area and height occupied), the relative position between the components - space size, device placement surface to ensure the electrical performance of the board and the feasibility and convenience of production and installation at the same time, should ensure that the above principles can be reflected in the premise of appropriate modifications to the placement of the device, so that it is neat and beautiful. Make it neat and beautiful, such as the same device to be placed neatly and in the same direction.