Power PCB internal electrical layer division and copper laying

A Power PCB layer and protel similarities and differences

Many of our designs use more than one software. Because protel is easy to get started, many friends learn protel first and then Power. Of course, many of them learn Power directly, and some use two software together. Since the two software have some differences in layer Settings, beginners can easily get confused, so let’s compare them side by side. Those who study power directly can also take a look at it to have a reference.


First look at the classification structure of the inner layer

Software name Attribute Layer name usage

PROTEL: Positive MIDLAYER Pure line layer

MIDLAYER Hybrid electrical layer (including wiring, large copper skin)

Pure negative (without division, e.g. GND)

INTERNAL Strip INTERNAL division (most common multi-power situation)

POWER: positive NO PLANE Pure line layer

NO PLANE Mixed electrical layer (use the method of COPPER POUR)

SPLIT/MIXED electrical layer (inner layer SPLIT layer method)

Pure negative film (without partition, e.g. GND)

As can be seen from the figure above, the electrical layers of POWER and PROTEL can be divided into positive and negative properties, but the layer types contained in these two layer attributes are different.

1.PROTEL has only two layer types, corresponding to positive and negative attributes respectively. However, POWER is different. Positive films in POWER are divided into two types, NO PLANE and SPLIT/MIXED

2. Negative films in PROTEL can be segmented by internal electric layer, while negative films in POWER can only be pure negative films (internal electric layer cannot be segmented, which is inferior to PROTEL). Inner segmentation must be done using positive. With SPLIT/MIXED layer, you can also use normal positive (NO PLANE)+ copper.

That is to say, in POWER PCB, whether used for POWER inner layer segmentation or MIXED electrical layer, must use positive, and ordinary positive (NO PLANE) and special MIXED electrical layer (SPLIT/MIXED) the only difference is the way of laying copper is not the same! A negative can only be a single negative. (It is not recommended to use 2D LINE to divide negative films because it is prone to errors due to the lack of network connection and design rules.)

These are the main differences between layer Settings and inner splits.

The difference between SPLIT/MIXED layer inner layer SPLIT and NO PLANE layer lay copper

1.SPLIT/MIXED: the PLACE AREA command must be used, which can automatically remove the inner independent pad and can be used for wiring. Other networks can be easily segmented on the large copper skin.

2.NO PLANEC layer: COPPER POUR must be used, which is the same as the outer line. Independent pads will not be automatically removed. That is to say, the phenomenon of large copper skin surrounding small copper skin cannot occur.

POWER PCB layer setting and inner layer segmentation method

After looking at the structure diagram above, you should have a good idea of the layer structure of POWER. Now that you have decided what layer to use to complete the design, the next step is to add an electrical layer.

Take a four-layer board as an example:

First, create a new design, import the netlist, complete the basic layout, and then add the LAYER setup-Layer DEFINITION. In the ELECTRICAL LAYER area, click MODIFY, and enter 4, OK, OK in the popup window. Now you have two new electrical layers between TOP and BOT. Name the two layers and set the layer type.

INNER LAYER2 name it GND and set it to CAM PLANE. Then click on the right side of ASSIGN network. This layer is the entire copper skin of the negative film, so ASSIGN one GND.

Name INNER LAYER3 POWER and set it to SPLIT/MIXED(because there are multiple POWER supply groups, so INNER SPLIT will be used), click ASSIGN and ASSIGN the POWER network that needs to go through the INNER layer to the ASSOCIATED window on the right (assuming three POWER supply networks are allocated).

The next step for wiring, the outer line in addition to the power supply outside all go. POWER network is directly connected to the inner layer of the hole can be automatically connected (small skills, first temporarily define the type of POWER layer CAM PLANE, so that all allocated to the inner layer of the POWER network and the hole line system will think that has been connected, and automatically cancel the rat line). After all wiring is completed, the inner layer can be divided.

The first step is to color the network to distinguish the locations of the contacts. Press CTRL+SHIFT+N to specify the network color (omitted).

Then change the layer property of the POWER layer back to SPLIT/MIXED, click DRAFTING-PLACE AREA, next draw the copper of the first POWER network.

Network 1 (yellow) : The first network should cover the entire board and be designated as the network with the largest connection area and the largest number of connections.

Network # 2 (green) : Now for the second network, note that since this network is located in the middle of the board, we will cut out a new network on the large copper surface that has already been laid. Or click on PLACE AREA, and then follow the instructions of the color rendering of cutting AREA, when double click finish cutting, the system will automatically appear cut by a current network (1) and (2) the AREA of the current network isolation line (because it is made cutting feature pave the way of copper, so can’t like cutting negative with a positive line to complete large copper surface segmentation). Assign the network name as well.

Network 3 (red) : the third network below, since this network is closer to the board edge, we can also use another command to do it. Click professional -AUTO PLANE SEPARATE, draw drawing from the board edge, cover the required contacts and then go back to the board edge, double click to complete. The isolation belt will also automatically appear and a network allocation window will pop up. Note that this window requires two networks to be allocated consecutively, one for the network you just cut and one for the remaining area (highlighted).

At this point, the whole wiring work has been basically completed. Finally, POUR manager-plane CONNECT is used to fill copper, and the effect can be seen.