Reflow Soldering

Reflow soldering is the modern mechanism for assembling most printed circuit boards today. It enables mass production at a very rapid rate by allowing placement of the components to be separated from the actual soldering process. This process is somewhat different from how somebody would solder by hand. When you’re hand soldering you’re treating one component individually and applying heat to each component at a time so the technique has to be a little bit different.

Reflow soldering is the most common method of attaching surface mount components to a circuit board, although it can also be used for through-hole components by filling the holes with solder paste and inserting the component leads through the paste. Because wave soldering can be simpler and cheaper, reflow is not generally used on pure through-hole boards. When used on boards containing a mix of SMT and THT components, through-hole reflow allows the wave soldering step to be eliminated from the assembly process, potentially reducing assembly costs.

The goal of the reflow process is to melt the solder and heat the adjoining surfaces, without overheating and damaging the electrical components. In the conventional reflow soldering process, there are usually four stages, called "zones", each having a distinct thermal profile: preheat, thermal soak, reflow, and cooling.

Soldering Irons

Soldering irons, a simple iron and a temperature-controlled one, need different wattages while working.

A 30-watt simple soldering iron is okay for modest electronics. Soldering ordinary through hole electronic components and thin wire, even the thin metal legs on direct current power plugs and sockets, should be fine.

While a temperature-controlled soldering iron needs much higher power than a simple iron, for example 80W or more. This allows it to maintain a relatively constant soldering temperature even it is being used at the same time, and heat parts with larger thermal conduction or capacity. It won't slow down an operator, and is a bit more flexible on what it can be used for than a simple iron. That is very important on a production line, or where a lot of soldering joints need to be made relatively rapidly. However, a simple iron is likely to drop too far below adequate soldering temperature, and slow the operator down which will cause boss much loss. 

PCB Design

With the rapid development of the latest technologies, it no doubt that in every few months, you can see a new “product for future” launched and it can really revolutionize how we live our lives. With advances in technology for consumer products, especially in the transportation and communications fields, we are now able to do more than we ever thought possible even a few years ago. As more and more products use printed circuit boards to get the job done, expands its capabilities and continues to grow in order to manufacture the top PCBs for your products and projects. Rather than being limited by the hardware available, you will be limited by just your imagination in the design process. Don’t worry about that, designers in EPCB can give you the most suitable suggestion for your design. 

Electronic Board Types

The term for an electronic board is a circuit board. There are three main types of circuit boards: printed circuit boards, stripboards and breadboards.

A printed circuit board functions by connecting various electronic parts in an electric device and providing them with mechanical support. It does this through conductive tracks, pads and laminated copper components. The printed circuit board is the most popular type of electronic board, and it can be found in most common electronic devices, including cell phones, radios and televisions.

A stripboard circuit contains a grid of holes bored into a plastic board and aligned copper strips on the other side of the board plastic. Circuit connections created on a stripboard are permanent. To create a system of connections on the board, the engineer therefore needs to manually solder in the copper strips that form the circuit. Stripboards are more ideal for smaller electronic connection needs.

A breadboard is a perforated plastic board with layers of metal alloy clips underneath the perforated plastic. It is quick and simple to construct. Unlike a stripboard, it is reusable, as a breadboard circuit can be adjusted by linking wires and leads to different holes each time a new circuit system is required.

Soldering Components on a Stripboard

A stripboard is a circuit board with holes and printed strips of metal. These boards are a good way of connecting simple to medium complicated circuits. Beginners are highly recommended to use stripboards in the beginning because you can control your connections and relatively easy to fix errors.

Soldering components on a stripboard: On the back side of the stripboard you can see several strips of metal which connect the holes either vertically or horizontally. Firstly, place all the components on the stripboard according to the schematic. Try to use the connections already on the stripboard as much as possible. Always think through where you want to place the components before you start soldering. After placing a component, bend its leads to make it stay in place when you turn the stripboard around to solder. Solder all the components to the stripboard and make sure you have good solder joints all over.

You can build all kinds of circuits! But a circuit with many connections can become a real hassle when you are trying to figure out which wire goes to where. You can first make sure all the connections are correct on your computer, then do it as per your schematic.

How to Use a Breadboard

A breadboard is a really simple way to put together a circuit. You don’t have to solder, just plug in the components. The breadboard has connections between its holes. Some are vertical connections and some horizontal connections. 

It’s common to use the vertical columns on the left and right for connecting the power supply. Each of these columns is connected vertically. So, if you connect 5 volts on the top hole of one of the side columns, you will have 5 volts in all the holes of this column. Some larger breadboards are split into two, so that the upper half of the left and right columns is connected and the lower half is connected. This is indicated by the vertical blue and red lines.

Breadboards are often used to build a prototype or to test a circuit, or a part of a circuit that you are unsure about. It is a better way to use breadboards for testing out new circuits. For example, suppose you want to build a microcontroller circuit that controlled relays with the output pins from the microcontroller. Then you would want a little driver on the output. If you are unsure about this circuit, you could throw it together on a breadboard quickly to make sure it works before you put it into your final design. It is really useful.

Soldering Tools That Make Your Life Easier

The soldering tools you need to get started with soldering are a soldering iron and some solder wire. But there are some other tools that will make your soldering much easier. Aside from the soldering iron and the solder wire, here are a few other useful tools that EPCB would recommend to have when soldering electronics.

Wet Sponge: A wet sponge is very useful for cleaning the tip of the soldering iron. The tip is hot so that it will oxidize very fast and get dirty. A clean tip transfers heat faster and makes your soldering easier. A sponge is so cheap, so you should always keep one together with your other soldering tools.

Tweezers: Tweezers are some very handy soldering tools. You use them to keep components in their place and to avoid burning your fingers when soldering. You can also use them for placing small surface mount components.

Solder sucker: The solder sucker is a mechanical vacuum pump that sucks the solder away from the solder joint when it is melted.

Solder wick: The solder wick is a tool you use for de-soldering. It is made up of copper threads that will “suck” the solder from the solder joint. The solder wick is used for removing small amounts of solder.