Which soldering iron is best for soldering microcircuits? — Machine tools, welding, metalworking
Choosing a soldering iron for radio amateurs is a very important point, since it is a key device for every radio amateur. However, all soldering irons or soldering stations have differences and are selected by radio amateurs individually, depending on the type of intended work and personal preferences. We also recommend reading the article about soldering basics.
Soldering iron designs
By design they are:
- Traditional (straight rod design).
- Guns (design of a soldering iron in the shape of a gun on which the working part is located at an angle).
- Soldering stations (complex equipment with a working part and a control unit).
How to choose a soldering iron for soldering microcircuits
Before choosing a soldering iron, let's figure out what they are.
Gas ones are more often used for soldering during installation work, for example, soldering in distribution boxes. They are convenient because they can work autonomously, but during operation they emit harmful substances and working with them for a long time is harmful to the health of both you and others. But for soldering microcircuits or other radio components, it would not be wise to choose such a soldering iron. It is extremely difficult to solder any board with it.
Electric ones, in turn, are the most common. Depending on the type of heater they are divided into:
- Spiral (nichrome)
- Ceramic
- Pulse
- Induction
Spiral is the most common of all electric heaters. The spiral heater provides reliable and durable operation at an inexpensive price, but has one drawback - a long heating time.
Ceramic is more expensive and quite fragile, however, it needs less time to heat up.
Pulse, with its rather high price, will be the best option. It heats up quickly and will not become unusable from a small impact.
If you are going to take up soldering seriously, and the range of proposed work will increase, pay attention to soldering stations. Induction heats up due to the inductor coil. This soldering iron does not need a thermostat, but you will have to select the desired temperature by searching through the set of tips.
Selecting the power of the soldering iron
There are soldering irons of different capacities:
- Low-power (from 3 to 10 W.)
- Medium power (20-40 W)
- High power (60-100 W)
- Industrial (more than 100 W)
Depending on the power, the purpose of the soldering iron changes. Soldering irons with a power of more than 100 W are used for soldering large metal products such as radiators, pots, and pipes. Soldering irons with a power of 60-100 W are designed for soldering really thick wires.
Soldering irons up to 10 W are designed mainly for soldering simple microcircuits, SMD elements and other miniature radio components.
So, answering the question of how to choose a soldering iron for soldering radio components and microcircuits, a good option would be to choose a low-power soldering iron to avoid overheating of miniature radio components and SMD elements. However, if you are an experienced radio installer, the best option would be a 20-40 W pulse soldering iron, which in skillful hands can be used for quick work with miniature radio components and other work around the house.
Soldering iron for microcircuits: how to choose a tip?
Of course, an important factor when choosing any soldering iron is the tip. However, the choice of sting is purely an individual preference. Choose depending on which tip you are comfortable working with; there are only a few recommendations for choosing. It is not recommended to use a tip larger than 3 mm. It is advisable to use a copper tip, as it is easy to clean and process.
The copper tip with a layer of aluminum is not processed, but is slightly subject to burning. There are both regular and heat-resistant stings. Heat-resistant ones can more easily withstand long-term work and exposure to high temperatures. If you are a beginner, then a straight sting is the best option.
Moreover, an advantage to the soldering iron will be a set of tips of different shapes, the ability to replace the tip and adjust its length.
A good soldering iron for microcircuits should have a flexible power cord and double insulation. Also pay attention to the handle. It must be well protected from possible overheating, therefore, unlike ebonite and plastic, wooden handles are recommended.
They are less susceptible to heating, unlike plastic ones, and lighter than ebonite ones, that is, they are more suitable for long-term work. Also an important indicator will be the function of constant temperature support and a thermostat, so as not to burn out the components when soldering.
Soldering iron equipment will make the work and maintenance of the soldering iron easier: a soldering iron stand, a sponge for cleaning the tip.
conclusions
If you have not decided which soldering iron to buy for soldering microcircuits, to summarize, we will emphasize the main recommendations and requirements so that you understand which soldering iron is better for soldering microcircuits and other components when looking at stands and shop windows for radio amateurs.
For inexperienced radio amateurs, it is advisable to use low-power soldering irons from 3 to 10 W. It is possible to use soldering irons with average power of 20-40 W to work with microcircuits and radio components, but there is a high probability of damaging the component during installation or dismantling. The wire must be flexible, long and double insulated. The tip is selected individually depending on preferences and type of work.
It is advisable to buy a soldering iron with a wooden handle. The type of soldering iron heater depends on the funds allocated for the purchase and the type of intended work.
It is desirable that the purchased soldering iron has a function of constant temperature control, a temperature regulator, a set of tips, an adjustment of the length of the tip, the ability to replace the tip and an addition, such as a stand for the soldering iron, a storage case, a cleaning sponge, etc.
You can buy a soldering iron on the well-known site - Aliexpress; we have made a selection of popular models in a separate article.
Source: https://stanki-info.com/kakim-payalnikom-luchshe-payat-mikroshemy/
How to desolder a microcircuit
The need to dismantle radio elements arises in several cases:
- Dismantling the faulty element;
- Incorrect installation of the radio component;
- Soldering from the donor board due to the lack of a new microcircuit.
In all these cases, except for the first, the main conditions are maintaining the integrity and working condition of the soldered part and the integrity of the printed circuit board.
Dismantled microcircuits
To carry out this work, it is necessary to observe accuracy and simple rules that were developed back when most of the range of radio components was in short supply. The urgent question was how to remove an expensive microcircuit from the board without damaging it.
Chip types
The wide variety of microcircuit packages has led to the fact that soldering techniques began to differ. Previously, the most widespread were microcircuits with pin pins for mounting into holes on a printed circuit board. Subsequently, with an increase in the degree of integration and the widespread use of automated soldering lines, surface mount elements with flat or ball leads began to be used.
ICs (integrated circuits) with solder pins are typically DIP and SIP packages with two and one row of pins, respectively.
Surface mounting ( SMD ) allows installation of ICs with pins of the following types:
- Flat leads brought outside the housing - SOIC, SOP, QFP (square housing);
- Flat legs, bent inward, under the body - SOJ, PLCC, QFJ;
- Ball terminals - BGA.
Each variety has several subspecies. The total number of housing types is in the dozens.
Safe work with semiconductor radio components
Before you unsolder a part from the board with a soldering iron, you need to know the following. Semiconductor elements are extremely sensitive to overheating. Also, tracks on a printed circuit board at high temperatures or when the soldering time is exceeded can peel off from the substrate or break, which is even worse.
Temperature conditions
Soldering station - operating principle and types
The temperature of the soldering iron tip should be 200-250⁰С. At higher temperatures, peeling of the printed tracks and overheating of the microcircuit may occur. The same goals are set for the soldering time of one leg - no more than 3 seconds.
Note! Some sites advise for dismantling to focus not on the temperature, but on the power of the soldering iron. It is not right. Their temperatures are the same, it’s just that a less powerful one may not be able to cope with melting the solder at the pin due to intense heat removal, and a too powerful one can easily overheat the pins and the board. The best option is a 40 W soldering iron.
Many microcircuits are sensitive to static electricity. It is necessary to work with an electrostatic wrist strap on and a grounded tool.
Electrostatic bracelet
Board design
DIY soldering station
Printed circuit boards differ in the number of printed layers and the method of installing radio components:
- Single layer;
- Double layer;
- Multilayer;
- For DIP elements;
- For SMD components.
One board can contain both DIP and SMD elements on one or both sides. Multilayer printed circuit boards, in addition to outer layers, have internal ones, which usually serve for general shielding or wiring of power circuits. Thus, the motherboards of modern computers or mobile phones have up to seven layers.
Multilayer PCB
Dismantling techniques
The method of soldering microcircuits depends mainly on the type of pins, although there are universal methods.
Dismantling the microcircuit with a soldering iron
How to test a zener diode with a multimeter
This is the most time-consuming and unreliable method. It is used only when the number of microcircuit legs is minimal. Before soldering microcircuits with a soldering iron, the tip of the tip is carefully tinned and cleaned of solder residues so that it remains only in the form of a thin film. The molten solder that surrounds the IC leg is transferred to the tip under the action of tension. By repeating the procedure several times, the leads are completely released.
Important! Before each touch of the board, the tip is cleared of solder. The touch time should not be more than three seconds. If the leg is not completely freed, you can only work on it after some time has cooled down. At this time, you can make the following conclusions.
Removing the chip using a razor blade
When working with planar elements, an ordinary razor blade will come to the rescue. For convenience, the razor blade is broken in half lengthwise. Leaning the blade close to the border of the terminal and the board, heat the scion until it melts. By inserting a blade between the leg and the board, they are separated. The blade is made of stainless steel, so solder does not stick to it.
Using dismantling braid
The special dismantling braid works thanks to the capillary effect, drawing in the molten material. You can use braided shielded cable with the same effect. The braid must be clean, without traces of oxidation. In order to improve the spreading of the melt, the braid is moistened with liquid flux.
Dismantling microcircuits using a desoldering pump
The desalination pump is a special piston that, when moving, draws in the melt, releasing the outlet. This method is suitable for working with DIP and SIP components.
Desoldering pump
Using medical needles
This method has proven to work best when dismantling ICs, especially for single-sided printed material. Double sided PCB can also be used to remove needles from syringes. When choosing a needle, you need to ensure that its inner diameter allows the leg of the microcircuit to fit freely, and its outer diameter allows it to fit into the hole on the printed circuit board. The tip of the needle is ground with a file until a smooth surface is obtained.
The needle is placed on the tip of the leg and the terminal is heated with a soldering iron. After the solder has melted, the needle is inserted into the hole of the board and smoothly rotated around the axis until the tin solidifies. After this, the needle is removed from the stem, which is now completely free. The needle material (stainless steel) is not tinned, so rotation around the stem is only necessary to make it easier to remove it from the hole.
Use of alloy rose
Using a rose alloy, you can desolder all the terminals of the IC at the same time, due to the fact that the low-melting alloy spreads between the terminals and evenly and simultaneously transfers heat to all of them from the heated soldering iron tip. After complete heating, the part is carefully removed from the board using tweezers.
This method has one disadvantage - after dismantling, it will not be possible to collect the remaining rose alloy, since it will be clogged with excess tin and lead, which will change its composition and melting point.
How to desolder a microcircuit from a board with a hairdryer
When working with SOJ, PLCC, QFJ and BGA packages, a soldering station or hair dryer with temperature control is required. Using the station, the entire section of the board is heated until the microcircuit is released, and using a hair dryer with a nozzle, a stream of hot air is directed to the terminals of the IC until they are released.
Radioelements must be desoldered at a temperature of 250⁰C. To prevent overheating, adjacent elements should be covered with aluminum foil.
How to remove capacitors from a motherboard
To desolder capacitors or other two-terminal elements, there is no need to use a special soldering tool. During the dismantling process, one of the terminals of the capacitor is heated, while simultaneously tilting the element so that the leg comes out of the hole. Next, repeat the same with the second leg, tilting the part in the opposite direction. To avoid tearing, do not press hard on the capacitor. By warming up both terminals in turn, they are gradually released.
Source: https://amperof.ru/sovety-elektrika/kak-vypayat-mikrosxemu.html
What temperature to solder microcircuits at?
Details Category: Beginners
It was said earlier about how to solder correctly - “How to solder correctly with a soldering iron.” But sooner or later the moment comes when you start soldering microcircuits.
Every person who understands little about microcircuits has asked the question: “How to solder microcircuits if there is a very small distance between them?” Let us remind you that there are two types of microcircuits. In this article I will explain to you how microcircuits are soldered, in which all the pins are located around the perimeter of the microcircuit.
Every electronics engineer has his own secrets on how to solder microcircuits. Some use solder paste, others solder each part separately, and some modify it for “wave soldering” (and make a small depression in the soldering iron tip, generously lubricate it with flux and apply it all over the micro-piece).
To be honest, I have not used this method, but I can try it. But most of all, I and other electronics engineers like another method. So let's get started.
Remember the original position
Each microcircuit has a kind of “key”. This is the mark from which the conclusions are read. In the circuits, the terminals are counted not as usual, but counterclockwise. It happens that even on the most ordinary board it is shown how the mikruha should be positioned correctly. Before unsoldering the microcircuit, remember how it stood initially, or better yet, sketch it.
Next, lubricate all the tracks with flux. For example, Flux Plus.
Dismantling the microcircuit
Let's set the temperature of the hair dryer to 350-380 degrees, and begin to solder our mikrukha around the perimeter in a circular motion. Perhaps in your kit you will have such a thing, I call it a “chip lifter”. If you have it, you are very lucky. As soon as you see that the solder is slowly melting, take the mikrukha by the edge and lift it up. If it rises partially, then you need to warm it up with a hairdryer.
If we lift the microchip with tweezers, then we have a lot of chances to tear out the contact tracks. Thanks to the antennae, the chip is unsoldered from the board when the solder is completely melted. The main thing in this work is not to skimp on flux.
Removing solder residues
It is necessary to remove old solder in order to level the surface. This will simplify the process of installing the chip in the future. In order to remove solder residues, copper braid and a soldering iron are used. To avoid soldering the tracks, you need to use our beloved Flux Plus.
At this stage, the main thing is not to overheat the tracks. Beginner radio amateurs make this mistake quite often. Overheating of the tracks can cause them to begin to peel off from the PCB.
Installing the chip
Some kind of mounds will appear on which you need to plant the mikruha. Using a cotton swab soaked in Flux Off, clean the surface of carbon deposits. At the end, lubricate it with flux again.
We install the mikruh according to the key, and holding the hair dryer as perpendicular as possible, move it around the perimeter. We can lubricate it with flux one more time, it won’t hurt. This is one of the easiest sealing methods. Good luck to you.
Source: https://steelfactoryrus.com/kakoy-temperaturoy-payat-mikroshemy/
What kind of solder do you use to solder microcircuits?
Every modern electronic device operates using chips of varying sizes and complexity. No product can work forever. Microcircuits are repaired using soldering. Working with them is a rather complex and delicate task. Due to the large number of contacts located as close to each other, their soldering requires maximum care and attention.
A regular soldering iron is not suitable for soldering microcircuits; for this you need to purchase specialized equipment. Also, special attention is required in the selection of consumable filler material. In order to make the work as easy as possible, it is necessary to use solder with a relatively low melting point.
The quality of consumables plays a huge role in the final result of soldering. Naturally, its cost is quite high, but it is fully justified by its high quality.
It is also worth noting that soldering contacts in microcircuits does not require a large amount of solder, which will allow you to use one package of the substance for a long time.
There are a large number of different models of solders, which differ from each other in chemical composition, physical properties and, of course, quality. This is due to their wide range of uses. Solder for soldering microcircuits is used everywhere by both amateurs and private professionals, as well as in huge large-scale production.
The choice of filler material for working with microcircuits is quite different from the selection of material for conventional soldering. Here, first of all, you need to pay attention not to the strength property, but to resistance to high temperatures, the ability to conduct electric current, etc.
The most popular models of solders for soldering microcircuits
There are a lot of different models of solders from various manufacturers, the main purpose of which is to work with microcircuit contacts. We can separately highlight a couple of domestic models that are popular in our country. One of these is solder for POS 61 microcircuits. Its chemical composition is very diverse and looks like this (values are indicated as percentages):
- Sn – 61;
- Pb – 38.5;
- Fe – 0.02;
- Bi – 0.01;
- Sb – 0.05;
- Ni – 0.02;
- S – 0.02.
This set of elements in the chemical composition of the consumable filler material allows it to acquire the following physical properties and mechanical characteristics:
- the substance begins to undergo a melting process when it reaches a temperature of 189 degrees Celsius;
- the density of deposited solder per square centimeter is approximately eight and a half grams;
- the material is capable of elongating relative to itself by approximately 45-47%;
- The impact strength of the material is 3.9 kilograms per square centimeter of the area of the deposited substance.
As an alternative to the solder described above, you can use the POS 30 model. In terms of the overall quality level, it is quite inferior to the previous model, however, the low melting point allows you to create comfortable conditions for soldering microcircuits. Its chemical composition consists of only two components (percentage values):
This simple composition provides the solder with the following technical characteristics:
- the substance begins to melt when it reaches a temperature of 183 degrees Celsius;
- the density of deposited solder per cubic meter is ten kilograms;
- Solder is capable of elongating relative to itself by almost sixty percent.
How to choose?
Naturally, you should not limit yourself to the two models described above. For each specific case, it may be necessary to use a filler material of a certain chemical composition to ensure the desired physical properties and mechanical characteristics. You should choose one or another solder model based on the properties you need.
First of all, you need to pay attention to the conductivity of electric current. If the resistance it has is low enough, then its use in soldering complex microcircuits will be impossible. Of course, for small soldering jobs done at home, you can use the simplest and most inexpensive option. But if you have to carry out large-scale work, then it is best to buy solder, the chemical composition of which is based on silver.
Also a very important characteristic is the temperature at which the substance begins to melt. Since the operating activity of almost any microcircuit rarely occurs at temperatures exceeding one hundred degrees Celsius, it is better to use consumables with a low melting point.
It is worth paying attention to the shape of the material. It is best if it is implemented in the form of a tube or rod, since such forms can provide maximum comfort during operation. With their help, it is very easy to take the minimum required amount of substance with a soldering iron.
Features of soldering work with microcircuits
When purchasing a particular model of solder, it is worth considering that soldering microcircuits has some differences compared to working with larger products. To work with small contacts, you need to use a small soldering iron with a sharp, flat tip. In no case should the operating power exceed the melting point of the consumable material. To improve the quality of the final result of the work, it is imperative to use flux in large quantities.
The most important difference between soldering microcircuits and working with other products is that any microcircuit needs to be cleaned of excess consumables after the work is completed. This should be done in order to eliminate the chance of a possible short circuit during operation of the microcircuit. This process is carried out using copper braid, which is also one of the features that requires working at low temperatures.
Source: https://svarkagid.com/kakim-pripoem-pajat-mikroshemy-3/
