How is the PCB routed at the power plane?

By default, no other signal lines can be placed on the power plane and ground plane

The power layer generally does not lay signal lines, usually need to divide the power layer into different power supply areas, wiring represents the division boundary, just use line.

1. AC input and DC output should have a clear layout distinction, and the best way is to be able to isolate each other.

2. The wiring distance between the input and output terminals (including DC DC conversion primary and secondary) should be at least 5 mm.

3. The control circuit and the main power circuit should have a clear layout distinction.

4. Try to avoid the parallel wiring of high-current and high-voltage wiring, measurement line and control line.

5. Try to apply copper on the blank board surface.

6. In the wiring connection of high current and high voltage, try to avoid long-distance connection with wires in space, and the interference caused by it is difficult to deal with.

7. If the cost allows, multi-layer board wiring can be used, and there is a special auxiliary power layer and stratum, which will greatly reduce the impact of EMC.

8. The working place is the most susceptible to interference, so try to adopt a large-area copper wiring method.

9. The wiring of the shield ground cannot form an obvious loop, which will form an antenna effect and easily introduce interference.

10. It is best to have a neat layout of high-power devices, which is convenient for the installation of radiators and the design of heat dissipation air ducts.

Reasonable layout of the power cord:

One of the keys to designing a high-speed PCB is to minimize the noise introduced by the voltage drop caused by the line impedance and the conversion of high-frequency electromagnetic fields. There are usually two ways to solve the above problems. One is power bus, and the other is to use a separate power plane for power supply.

The latter alleviates the problems of voltage drop and noise to a large extent, but considering the complex process, expensive expenses and long production cycle of multilayer PCBs, general designers prefer to use the former.

The power bus technology is adopted, each component is suspended on the power bus, so it is also called the suspended bus, the width of the power bus is usually wider than the ordinary signal line, after the use of bus technology, although the voltage drop and noise problems can be reduced, but they still exist.

First of all, let's look at the voltage drop problem, assuming that the power supply voltage is 0A, AB, BC, CD, BE, AF and the resistance of each section of the wire is 200mA, and the fan-out or suck-in current of each component on the PCB board is 200mA, and two ideal assumptions are made: 1. The sudden change in voltage and current caused by the sudden corner of the power line at a, b, and c is not considered;

2. The boundary effect caused by the mutual conversion of electromagnetic fields of boundary elements (1,4,9,12) is not considered. Then the current in the wire OA is, the current in the wire AB is, the current in the wire BC and CD is, and the voltage on the last element 9 is: .

3. Due to the voltage drop generated by the impedance of the line, the deviation is almost 10, which is quite large for a voltage, and with the development of the IC in the direction of low voltage, there is already a lot of work in the IC or even lower, so such a large voltage drop will be very fatal. At the same time, under this power bus, noise is also a big problem, and the noise generated by each device will be coupled to the element 13 through the power supply, which means that the device 13 superimposes the noise of 13 elements, which will easily cause the device 13 to not work properly.

The top and bottom wiring of a PCB (Printed Circuit Board) refers to two different layers of copper foil on the PCB, which are located on the top and bottom of the PCB. The main difference between them is the devices and elements to which they are connected.

Top cabling is often used to connect devices, IC chips, or other important high-frequency signal components, which are sensitive to signal quality and EMI rejection. On the other hand, the underlying cabling is typically used to connect lower frequency components such as power, ground, and signal pins. Since signal quality is less sensitive when connecting lower frequency components, low-level cabling can be used to reduce costs and increase routing density.

When designing a PCB, you need to decide which routing method to use based on the connection needs between the components and the signal characteristics. At the same time, it is important to consider the impact of PCB cost, reliability, and EMI. In summary, understanding the difference between the top and bottom wiring of a PCB is important for designing a high-performance PCB.

1.Top Layer Routing: - Top layer routing is the top layer of the circuit board and is located on the top layer of the board.

Slow Decay - The top layer cabling is usually used to arrange more conventional signal lines, power lines, and some common component liquid ballasts, such as resistors, capacitors, transistors, etc. -Component pins connected to the top-level routing can be connected to the bottom layer via via, allowing signals to be transmitted between different routing layers.

2.Bottom Layer Routing: - The bottom layer is the bottom layer of the board and is located on the bottom layer of the board.

The underlying cabling is usually used to process more complex signals, such as high-speed signals, differential signals, etc. These signals require stricter wiring rules and special shielding to ensure signal integrity and suppress interference. - Similarly, the pins of the components connected to the underlying wiring can be connected to the top layer through a VIA to enable the transmission of signals between the different wiring layers.

In general, top-level cabling is mainly used for more conventional and simple signal cable arrangements, while low-level cabling is more suitable for complex and high-performance signal arrangements. With proper routing planning, it is possible to ensure that signals are transmitted and connected to each other between different routing layers, while improving the performance and reliability of the circuit board.

How to lay the ground wire and the power cord pro in PCB wiring! Hello, glad to answer for you. Ground wire and power line design rulesThe ground wire (layer) and power line (layer) design of digital circuits should generally follow the following principles:

a) The ground wire is generally composed of a dense ground network with a wide printed wire, and it is recommended to connect all unused copper surfaces to the ground, and the ground plane should be used if necessary; b) The power line should be close to the ground wire, for ECL and TTL circuits, it is recommended to use a wide printed wire ruler to form a dense power supply network, and the power plane should be used if necessary; c) The use of common ground and power lines for digital circuits (especially TIL circuits) and sensitive analog circuits should be strictly avoided; TTL circuits and ECL circuits generally should also have their own independent ground and power lines. The PCB wiring rules for the ground wire and the power cable are as follows: 1. Add a decoupling capacitor between the power supply and the ground wire.

2. Try to widen the width of the power cord and ground wire, preferably the ground wire is wider than the power cord. 3. The PCB of the digital circuit can be used to form a circuit with a wide ground wire, that is, to form a ground network to use, and the ground of the analog circuit cannot be used in this way. 4. Use a large area of copper as the ground wire, and connect the unused places with the ground on the printed board as the ground wire, or make a multi-layer board, and the power supply and the ground wire each occupy a layer.

Check the rules a) After the wiring design is completed, it is necessary to carefully check whether the wiring design group is in line with the rules formulated by the designer, and it is also necessary to confirm whether the rules formulated meet the needs of the printed board production process. b) Whether the distance between lines and lines, lines and component pads, lines and through holes, component pads and through holes, and through holes and through holes is reasonable and whether they meet the production requirements. c) Whether the width of the power cable and the ground wire is appropriate, whether the power supply and the ground wire are tightly coupled (low wave impedance), and whether there is still a place in the PCB where the ground wire can be widened.

d) Whether the best measures have been taken for the critical signal lines, such as the shortest length, the protection cables, and the input and output lines are clearly separated. e) Whether the analog circuit and the digital circuit part have their own independent ground wires. f) Whether the graphics (such as icons, annotations) added to the PCB will cause a short circuit in the signal.

g) Modifications to some ideal line shapes. h) Whether there is a process line on the PCB, whether the solder mask meets the requirements of the production process, whether the size of the solder mask is appropriate, whether the character mark is pressed on the device pad, etc. i) Whether the outer frame of the power supply stratum in the multi-layer board is reduced, such as the copper foil of the power stratum exposed outside the board is easy to cause a short circuit.

Hope mine can help you! Do you have any other questions?

Your question is too vague, is it PCB board wiring or something else? What software do you use? What do you want to achieve?

PCB Routing Rules & Tricks Hello Glad to answer for you. 1. When the input is a small signal, and the output is a relatively strong power signal that has been amplified, the input signal and the output signal should be avoided when the board is laid out, and the small signal and the power signal can not be flat when the last resort is necessary 2, the signal and the power supply are separated when the system is working, the composition of the power supply is not pure, in order to prevent interference, the signal line should be avoided from walking flat with the positive pole of the power supply, especially the high-frequency circuit powered by the switching power supply 3, High frequency and low frequency go separately This does not need to be explained, high-frequency signal radiation can also cause the stability and noise of the low-frequency part of the unbridled 4, reserve enough wire diameter and safety spacing The current PCB manufacturing technology is becoming more and more sophisticated, but we can not go to the limit, although now many manufacturers can do the wire diameter, spacing, in the actual product design, if the circuit is not particularly small, we are still at least greater than it is appropriate, so as to improve the reliability of PCB production, so as to avoid the phenomenon of PCB short circuit and open circuit 5, The hole is equal to greater than, too small when PCB processing is inconvenient, too small hole is easy to break the drill bit, the pad aperture of the plug-in components should be greater than the pin, especially the metallization hole of the double-sided panel, the diameter of the component pin is, the hole of the pad is also, after the metallization hole will be less than the diameter of the pin 6, avoid going 90 degrees at right angles when wiring, and it is strictly forbidden to avoid high-frequency signals to prevent the signal line from radiating outward before the signal line becomes cracked, and the diagonal line can also shorten the wiring distance.

1.Control the direction of the tracesWhen the PCB is routed, avoid forming the same direction of different signals in the adjacent layers, and the traces of the adjacent layers should be orthogonal to avoid unnecessary interlayer interference.

2.In order to avoid the antenna effect caused by wiring and reduce unnecessary interference, radiation and reception, it is generally not allowed to appear at one end of the floating wiring.

3.When controlling the length of the traces, the length of the traces should be as short as possible to reduce the interference caused by the length of the traces. When some systems have strict timing requirements, the length of the PCB traces needs to be adjusted.

4.Control the length of the trace branchesWhen the PCB is routed, try to control the length of the trace branches so that the branch length is as short as possible.