Advanced understanding of 2 Layer pcb manufacturing (Beginner’s Guide)2020-04-21
Learn to draw a double layer PCB board
2 Layer pcb manufacturing has become very popular among all electronic industries. PCB board is an important electronic part and the mother of all electronic components. Moreover, it has become more and more complicated from the beginning of the last century to the present.
From single-layer to double-layer, four-layer to multi-layer, the design difficulty is also constant increase. Because the double-layer board has wiring on both sides. It is very helpful for us to understand and master its wiring principles.
What is a pcb printed circuit board? (pcb board)
A PCB board has two sides, that is:
- the top layer and
- the bottom layer
During 2 Layer pcb manufacturing with PROTEL, in Top Layer draw wires to connect components. That is:
- Draw on the top layer
- Select BottomLayer
- Draw wires on the bottom layer to connect components
- The above is to draw a double-layer PCB, meaning on a PCB board Draw wires on the top and bottom layers.
- Click Design → Layer Stack manager to jump to the layer management.
- Similarly, at this time, you click the TopLayer selection on the left side of the figure, and
- Then click Add TopLayer in the upper right corner to add an intermediate signal between the Top Layer and Bottom
The layer of Mid-Layer, adding two times is the middle layer of two layers, plus the top layer and the bottom layer is 4 layers. Drawing wires on these 4 layers to connect components is to draw 4 layers of PCB.
Let’s take a look at the wiring principle of PCB double board.
What is 2 layer pcb?
The double-layer PCB is a PCB specification commonly used in the general electronics industry. In addition to the double-layer board, there are more layers of PCB boards such as 4, 8, 12 and so on. Depending on the needs, sometimes due to the volume relationship, the circuit structure is dense.
In the case where single-layer and double-layer may not be satisfied, you will need to use a multi-layer board. And the design skills will be different. Same is the case with 2 Layer pcb manufacturing.
But to know the double-layer board, basically already contains all the knowledge of PCB Layout. So, I propose to know the double-layer board as an introduction.
Definition of the number of layers-2 Layer pcb manufacturing
The definition of the number of PCB layers is to use the plane that can be routed as the definition of the number of layers. For example:
- for a single-layer board, only a single plane can be routed
- a double-layer board can be routed on both the front and back sides
- and a multi-layer board is like a sandwich Just like cookies, sandwich the other layers of the circuit.
What will there be in the 2 Layer pcb manufacturing?
The 2 Layer pcb manufacturing is actually the same as the single-layer board, with only one additional via (VIA). Usually on a single-sided PCB, we can see:
Used to mark part number, part appearance, or other notes.
Why does Layout draw the appearance of parts?
The reason is very simple, has the following two functions
- During layout, the layout engineer can check whether there is interference based on the outline of the parts drawn.
- When 2 Layer pcb manufacturerinserts the plug, he can see where the parts are and the direction of the parts. If the position and appearance of the parts are not marked, the whole board looks like only dense holes. And copper foil, it will become impossible produce.
b. Solder joint (PAD)
2 Layer pcb manufacturing companies use Solder joints to fix parts where tin is eaten. There are two main types of solder joints:
- one is DIP type solder joints, and
- the other is SMD type solder joints.
The difference is that DIP solder joints will have holes, while SMD Type solder joints are usually flat.
What is DIP? 2 Layer pcb manufacturing
DIP originally refers to the type of IC package. It is the component itself with pins, which will penetrate all the layers when installed on the PCB board. So, I don’t know what the reason is, as long as it has pins Components, they are called DIP components. When they pass through all the layers during installation, so the PAD of DIP must have holes.
What is SMD?
According to the 2 Layer pcb manufacturing companies SMD and SMT are both said to be one. One is the surface-adhesive component SMD and the other is the surface-adhesive technology SMT. As the name suggests, this type of component is adhered to the surface of the PCB board during installation. But there may be VIA).
Hole, irrigation hole (VIA)
The hole refers to the hole where the pin of the DIP component is to be inserted. And VIA refers to the hole connecting the upper layer and the lower layer on the line. Furthermore, the two holes are basically the same. Except that one will insert parts and the other will not insert parts.
Difference, so usually the hole for inserting parts will be larger, while the hole for VIA will be smaller.
In addition, as mentioned above, VIA is usually used to connect the upper and lower lines. But the same DIP plug hole also has the same function. Simultaneously, in the current manufacturing process, the through hole usually has copper plating. So, it also has the same function as VIA.
Copper foil in 2 Layer pcb manufacturing
In 2 Layer pcb manufacturing, copper foil is the circuit on the surface of the PCB board. It connects the components to each other according to the design of the circuit diagram. Moreover, on the PCB board, the copper foil will be thick and thin. Because the circuit characteristics are different.
The thinner the copper foil can carry the smaller the current. So, when the loop current is large, you must use the corresponding thickness of copper to work with foil, just like a water pipe. If the water flow is large, you need to use a large aperture. If the water flow is small, you can use a thin tube. In addition, Trace is not necessarily slender, it can also be a large area, called copper.
Anti-welding in 2 Layer pcb manufacturing
Solder-proof means that those places do not want to be welded. It is a blocking medium. Because the commonly used material on the PCB board uses copper as the material of the circuit. So, if there is no solder-proof treatment, in 2 Layer pcb manufacturing process it will cause tin to be eaten in places where you don’t want to eat tin. Furthermore, it will cause short circuit and other problems.
If bare copper is not solder-proofed, the copper will oxidize due to contact with air for a long time, causing it to be bad.
How to draw a double layer PCB board?2 Layer pcb manufacturing techniques
To draw a good PCB requires more practice, more reference and learning some skills of senior engineers. As a beginner, you must have the following good habits:
- ask more
- look more
- learn more
- practice more
- Similarly, communicate to understand the power of this circuit themodule and the sensitive information of each module
- Determine the general placement of the module circuit according to the learned module information and the location of the PCB shape interface and complete the layout;
- Talk about the reasonable placement of the relevant components of the corresponding function block.
According to the 2 Layer pcb manufacturing company, process the power ground signal line carefully. For example, determine the width of the trace according to the size of the current. Whether to do the same length processing according to the signal line requirements, etc.
The PCB Layout file has the concept of “layers”. Objects with different properties are sequentially stacked on a plate to form a PCB board. So basically 2 Layer pcb manufacturing will have the following layers:
- Top text
- Top line
- Upper most layer solder mask
- Bottom line
- The bottom solder mask
- Underlying text
- Drilling position
Precautions for 2 Layer pcb manufacturing
- A 2 Layer pcb manufacturingcompanyor an individual should maintain at least 6mil signal line, 20mil power supply, 13mil via diameter
- The important signals of components go to the top, the ground loop goes to the bottom
- Reasonable layout and traces are separated as much as possible
- Isolate the gap as short as possible and add a feedback path (reduce the long feedback path)
- The decoupling capacitor is as close as possible to the IC to reduce loop inductance
- Furthermore, as far as possible, assign a return circuit to each digital signal on the connector
7.Do not connect all power supplies to 10uf 0.1uf 1uf, you can consider using 22uf
8.Different power supplies are separated by 0R resistance or inductance
9.Add intuitive silk screen information