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- October 24, 2022
- PCB knowledge
- (0)
- 06 mins
What are the different PCB components and their functions
In many ways, PCB components are core elements of a PCB. There is no functionality without them. If any parts of a PCB component fail to function properly, the whole PCB will be ruined. Understanding their appearance and how they work to prevent such problems is important.
What is a PCB component? What components are PCBs made of, and what are their functions?
A printed circuit board (PCB) is a flat board with electrical components to create an electronic circuit. The major PCB components are:
- Conductors: These are the wires that connect all the components. It can use copper or other types of metal, such as aluminum or gold. The conductors should be thick enough so as not to break easily and thin enough for proper insulation from other parts.
- Solder: A solder is a combination of metals (lead and tin) heated to melting point and used to connect PCB components by flowing through holes in the board and around conductors (wires).
- Resistors: Resistors have a fixed resistance value, and they change their resistance depending on the amount of current passing through them. They are used in circuits where it is necessary to reduce or increase current flow depending on the application needs (e.g., dimmer switches).
- Capacitors: Capacitors store energy in an electric field between two plates separated by an insulating material called dielectric material, which can be air or plastic film (polyester, polypropylene, etc.).
What are the features of PCB components?
PCB components are the essential building blocks of any PCB. They are small but very important pieces that make up the entire circuit.
The following are some features of PCB components:
High-quality materials: Since these are part of an electronic device, they should be made from high-quality materials. This means they should be durable and withstand harsh weather conditions such as high temperatures or moisture.
Copper or tin plating: A good PCB component has copper or tin plating to be soldered easily onto the circuit board.
Lead-free or leaded solderability: Some components have leaded solderability while others have lead-free solderability. The former contains lead, while the latter does not include this element. Leaded solderability allows for easier soldering, while lead-free solderability makes it more difficult to solder but assures that there will be no lead contamination in the device when used.
Stainless steel housing: Stainless steel housing is used for some types of PCB components because it helps protect them from damage caused by water or other liquids present in any environment where they will be used (like marine environments).
How to identify PCB components?
To identify the PCB components, designers need to know the following information:- The number of pins on each element.
- The size of each component.
- The type of each component (NPN, PNP, etc.).
- The value of each component’s resistance and capacitance (if applicable).
How do you layout PCB components?
There are several ways to layout PCB components:
- Layout the components manually, using a PCB layout software or an auto-router.
- Use PCB layout software to auto-route the board and manually edit the traces to add missing pads or fix mistakes.
- Use a PCB layout software with embedded auto-routing capabilities and manually edit the traces to add missing pads or fix mistakes.
The first method is not recommended because it is time-consuming. The second method is better but can still be frustrating if designers need to fix many errors by hand. The third method is the best because it will give the most control over the design while allowing a designer to use auto-routing if desired.
How to choose the right PCB components?
Choosing the right PCB components is an important part of designing a PCB. The wrong choice can make the design harder to manufacture and even damage the board during operation. Here are some considerations before choosing the right PCB components.
PCB design: The type of circuit and intended use determine the number of components used on a PCB. For instance, an audio amplifier requires few components, while a digital circuit requires a large number of them.
Consider component footprint: When choosing a component, look at its footprint (the outline of its shape). Ensure that it fits on the board and doesn’t overlap with other components.
Follow acceptable grounding practices: Some components require special grounding rules to work properly, so ensure to know them before placing them on board.
Required space component size: Some components have required spaces around them to work properly — things like heat sinks, fans, and chipsets all need space around them to operate correctly. Ensure a proper plan when designing the board layout so that nothing gets too crowded or overheats during use.
How to solder PCB components?
- Prepare the soldering iron, solder, and flux.
- Use a small flat-head screwdriver to remove any protective film on the pads of the component.
- Apply some solder to the pad and place the component in place. Ensure to align it properly with other components on the board. Also, ensure that no component pins are bent or broken off at this stage.
- Heat the soldering iron and apply some solder to its tip by touching it against a sponge or wet sponge (it is advisable to use a damp sponge as it will remove impurities from the end of the soldering iron)
- Place the tip of the soldering iron onto one side of the component pin that is sticking out from its socket or pad, and hold it there firmly until the solder melts and flows onto both sides of it; ensure not end up with too much solder on one side only (this can result in an electrical short between two parts).
How to prevent the aging of PCB components?
The most common way to prevent the aging of PCB components is to use a solder mask. The solder mask protects the copper layer from oxidation by covering it with a protective layer. It is usually made of green or blue ink and is applied to the desired areas on a PCB. The solder mask can also prevent components from oxidizing if exposed to high temperatures or humidity.
The second method involves using a conformal coating (also called “conformal coating”). A conformal coating is an organic or inorganic substance sprayed or brushed onto an electronic device before it is assembled. The purpose of this substance is to seal off electrical circuits, prevent corrosion, and keep out moisture and other contaminants.
Considerations when ordering PCB components
When companies order PCB components from a manufacturer, they generally have a specific set of considerations for the end product. The most common are:- Selection of a channel
- Recognize the manufacturer’s part number correctly (MPN)
- Size of the order
- Ensure consistency of parts
- Think about the anticipated cost issue.
Conclusion
PCB components are essential in the manufacturing of PCB boards. They permit the electrical circuit to do what it ought to be doing. Without them, there wouldn’t be a PCB board to speak of.
Learning about PCB components and their functions is the first step to understanding the various parts of a printed circuit board assembly. We’ve created a complete guide about PCB components and their functions. It will help better understand the use of PCB components and how to use them in the PCB design.
