The PCB Editor of the Altium Designer Program uses the concept of Rules to define the requirements of a design. These rules collectively create a 'command set' for the PCB Editor to monitor. When drawing paths, you can adjust thicknesses, openings, plane link styles, orientation over styles, and so on. It covers every aspect of the design, such as, and most of the rules can be monitored in real time by the online Design Rule Checker (DRC).
Design rules target specific objects and are applied hierarchically. In other words, even the way the rules work varies in a certain order of priority.
Since PCB Editor is rules-based, taking the time to set the rules at the beginning of the design will allow you to continue the work of designing safely and effectively.
Basics of PCB Rules System
There are several features that distinguish the rules system built into Altium Designer's PCB Editor from other PCB design programs:
Rules are separate from objects
No rules are added as an attribute of an object. Instead, it is added to the global rule set, and then its scope is determined to apply to that object. This allows rules to be applied to multiple objects, modified, or applied to different objects; otherwise, if you have to change the rule attributes at the individual object level, it will be more laborious to do so.
Rules are targeted (scoped) by writing a query
Instead of using a set of fixed, predefined rule scopes, a flexible query system is used to identify objects to which a rule is applied. This gives you precise control over the goal of each design rule.
Rules for any design case
Of the same type, multiple rules can be defined and targeted to different sets of objects. This provides full control over the definition of board restrictions. For example, different width rules can be defined to route paths in different widths, different layers.
Every rule has a priority
Any design object can be targeted by multiple rules of the same type that address public and more specific situations. Rule priority is used to resolve any rule disputes. The system simply reviews the rules from highest to lowest, and the scope expressions select the first one that matches the controlled object(s).
There are two types of rules
Unary rules (rules that define the required behavior of an object) and binary rules (rules that define interaction between two objects).
Now we can slowly review alitum designer's PCB Rules section. At this point, we must bear in mind that there are rules here that we should pay attention to, perhaps tens, hundreds. We will tell you about a few examples that are important and are often used. Then all you have to do is shape this situation according to your needs.
Introduction to PCB Rules
First, we press the Rules tab from the Design section of our interface. Then we already have our first main interface.
The branching drillthrough system on the left lists different rule categories. Expand a category you want to view existing individual rule types. As you expand, you'll see values that are already set.
On the right side, all important details about the rules of the main title we have chosen on the left side are presented. In fact, that's what the whole system is all about. Let's see a few rules.
Creating a New Rule
When you want to create a new rule, all you have to do is press the New Rule tab. This allows you to create a rule under any heading you want. Let's reinforce this with an image.
When you press this button, your new rule will now be established. Then you can click on it and edit the rule as you like. For example:
If you select width from Routing. Then, if you set the max width to 1mm in the top layer section, no path thickness you draw will exceed 1mm when you switch to pcb design. Or if you say min width 0.250mm, the thickness will never be less than 0.250mm. So why do we need this situation?
There may be many reasons for this, but one of the most common ones is the limits set by our manufacturer. For example: if the min path thickness that can be drawn in a PCB production company X is 0.15mm, it is not possible to produce a PCB there with a thickness of 0.14mm. In these cases, this Rule part helps you so that you do not get into those troubles.
We can think of it as the same thing, it allows you to assign the rules set by our manufacturer there and make an error-clear design. In this way, we also save time.
In addition to this manual method, Altium Designer also includes the Rule Wizard. This helps you do it a little faster. Let's examine it with the images below.
In fact, as you can see, you can select the desired rule here and include it in your project. These rules can be many parameters such as road thickness, via sizing, distance of two paths with each other, min and max value of the angle of the path. It's entirely up to you to set them up.
In some cases, it is necessary to define the general rules that cover the requirements and then override them with certain rules in certain cases. For this to be possible, an object is targeted by multiple rules of the same type. Then, when we sort them according to a priority, we can achieve this situation.
For example, to specify the path thickness that is most commonly used on your card, you define a single rule that applies to each path on the card. This rule can then be overridden for a specific path by adding another rule of the same type but with a higher priority.
Let's see how this rule is prioritized.
In fact, the rules can be prioritized in such a simple way.
Let's see how to delete the rules we created last time. For this, we click the delete Rule button on the rules tab. Then we give the approval. It's actually as simple as that.
In fact, this is how the rules tab will be explained in Altium Designer. Now you can incorporate any rule you want into your project and make more accurate and professional designs in this way.