Standard of industrial control board and pcb design layout

The industrial control board is an important part of the industrial control computer. To measure a PLC industrial control board, it needs to be determined from its chipset, planning and layout, and work and materials. How to select a suitable PLC industrial control board? Next, we will talk about how to express the quality of the IPC mainboard from two aspects: the wiring planning and layout of the IPC mainboard and the materials used for the IPC mainboard.

The PLC industrial control board is an important part of the industrial control computer. To measure a PLC industrial control board, it needs to be determined from its chipset, planning and layout, and work and materials. How to select a suitable PLC industrial control board? Next, we will talk about how to express the quality of the IPC mainboard from two aspects: the wiring planning and layout of the IPC mainboard and the materials used for the IPC mainboard.

Industrial control panel

PCB layout of PLC industrial control board

In terms of layout, PLC is mainly represented by the organization of various components and the routing of lines. In Zechuang Weiye's view, a good PLC industrial control board is a fine work of art. The chipset supplier will provide the chipset planning guide (CHIPSET DESIGN GUIDE) when shipping to the main board manufacturer of the industrial personal computer. Generally, there will also be a template according to the specification, which is called the engineering board.

PLC industrial control board

European and American manufacturers often follow the planning of the specification board, and will do very well in line with the standards provided by the official chipset. This practice ensures functions, but the price is difficult to control. In order to balance the cost, manufacturers in Taiwan often make contributions to the structure and layout of the IPC mainboard, often incorporating some common planning.

Structure and material of PLC industrial control board

(1) Now, in order to save costs and reduce prices, some manufacturers of IPC mainboards can stand firm in the market. They not only do not use the public version planning for the number of board types, but also make corresponding adjustments on the materials and accessories of IPC mainboards. They are only satisfied with the basic functional requirements of chipsets. This cost reduction is a test of the manufacturers' ability to plan and layout of IPC mainboards.

Put the same number of expansion bits in a smaller space, and also maintain stability and limit interference. In this way, the rationality of the main board structure organization planning of the industrial personal computer is particularly important. A little unreasonable planning will lead to a crash. In this regard, the weak businessmen simply make mistakes in these places. The instability and poor function of the main board are caused by this. So, if there are no special requirements, It is still better to choose the IPC mainboard of the public version plan. How to distinguish whether it is a public version plan depends on the user's mastery of the chipset.

(2) The orientation of the interface components on the main board of the IPC is generally fixed and cannot be changed at will. This is the case for expansion slots such as PICMG and interfaces such as keyboard, mouse and USB. They need to cooperate with the holes on the chassis to maintain relative orientation. However, in some cases, new chassis baffles will be provided to replace the built-in baffles of the chassis to complete the new interface layout.

(3) For the layout of CPU and chipset, because the circuit connecting CPU and CHIPSETS is important, chipset has special planning requirements, and chipset manufacturers also have very clear requirements for the planning of CPU, chipset and its surrounding areas, so they almost choose the public version for layout planning.

(4) Except for the expansion slot, CPU and CHIPSETS, other components can be easily organized. For example, the ATX power interface socket should be planned to be far away from the CPU fan, so that the chassis can have better heat dissipation.

(5) The layout of the main board of the industrial personal computer is reasonable. Some planning of the main board of the industrial personal computer is not very comprehensive. If you choose to purchase, you need to pay attention to some details, such as some capacitors near the CPU interface of the main board of the industrial personal computer will affect the device of the fan. These are all operations that you should pay attention to when you choose to purchase.

PCB design

Wiring planning of IPC mainboard

(1) Before talking about the wiring planning, Zechuang Weiye first told us the concept that the gap between the Beiqiao chip and the CPU and the memory is the basic requirement of the main board planning of the IPC, that is, the so-called "equal length of clock lines". We know that the Beiqiao chip, as the bridge between CPU and memory, is very sophisticated in layout. At present, some industrial computer mainboard manufacturers with research and development strength choose the wonderful plan of rotating 45 degrees in the organization and layout of Beiqiao chips, which not only shortens the routing length between Beiqiao and CPU, memory slot, AGP slot, but also makes the clock line equal in length.

(2) The wiring planning on the main board of the IPC is a relatively professional knowledge, which requires different planning methods depending on different circuit characteristics. The "serpentine wiring" selected on the main board of the IPC is very sophisticated. Some people think that the more serpentine wiring, the higher the planning level. This concept is wrong.

There are two reasons for choosing serpentine wiring: one is to ensure that the wiring lines are of equal length. As the clock line from the CPU to the North Bridge chip is different from the lines on ordinary electrical appliances, the signals running at a high speed at a frequency of about 100MHz on these lines are very sensitive to the length of the line. Unequal length clock wiring will cause the signals to be out of sync and thus form an unstable system, so some lines need to be routed in a zigzag way, To adjust the length;

Another common reason for using serpentine wiring is to minimize the impact of electromagnetic radiation (EMI) on other parts of the motherboard and the human body. High speed and monotonous digital signals will greatly interfere with the operation of imitation equipment on the motherboard. A simple way to suppress EMI is to plan serpentine cabling to absorb as much radiation as possible.

The use of serpentine wiring has the above advantages. It does not mean that the more serpentine pcb wiring is used in the wiring planning of the main board of the industrial computer, the better. Because too much and too dense main board wiring will cause uneven density of the main board layout of the industrial computer, which will have a certain impact on the quality of the main board of the industrial computer. Good wiring should make the density of each part of the line on the main board of the IPC slightly different, and should be evenly distributed as far as possible, otherwise it is very simple to form the instability of the main board of the IPC. How to choose a suitable PLC industrial control board is introduced here today, hoping to help us.