How to Desolder IC from PCB Safely and Easil

Estimated reading time: 12 minutes

Have you ever tried to fix a broken electronic device? Maybe your old game console stopped working, or a car key fob failed. Often, the problem is just one small black chip. This chip is called an Integrated Circuit, or IC. To fix the device, you have to take the bad IC off and put a new one on.

This process is called desoldering. For many beginners, learning how to desolder IC from PCB feels scary. They worry about burning the green board. They worry about ripping off the copper pads. These are real risks. But, if you use the right methods, it is actually quite safe.

You do not need to be an engineer to do this. You just need patience and a few simple tools. In this guide, we will teach you everything. We will start with the basics. Then, we will show you different ways to remove different chips. We will use simple words and explain why we do things, not just how.

So, get your tools ready. Let’s learn how to save your electronics.

Understanding the Challenge

Before we start, we need to understand the material we are working with. Solder is a fusible metal alloy, typically composed of tin and other elements, used to form a permanent, electrically conductive bond between component leads (such as IC legs) and the copper pads on the Printed Circuit Board (PCB).

To remove the IC, you must melt the solder on all the legs. If one leg is still solid, the chip will not move. If you pull it while it is solid, you will rip the copper pad off the board. Once the pad is gone, the board is very hard to fix.

The Two Main Enemies

1. Oxidation: Old solder is dirty and gray. It does not melt easily. It forms a skin that blocks the heat.
2. Thermal Mass: Some parts of the board are thick. They absorb heat very fast. This makes the solder get cold quickly.

We will show you how to beat these enemies.

Know Your Chips (DIP vs. SMD)

You need to look at your board. What kind of chip are you removing? There are two main families.

Through-Hole Technology (DIP)

These are the older style chips. They look like bugs with long legs. The legs go through holes in the board to the other side. You usually solder them from the bottom.

• Common name: DIP (Dual In-line Package).
• Difficulty: Medium. You have to clean the hole completely.

Surface Mount Technology (SMD)

These are modern chips. They sit flat on top of the board. The legs do not go through holes. They are soldered to pads on the surface.

• Common names: SOIC, QFP, SOP.
• Difficulty: Harder for beginners because pins are small. But easier if you have hot air.

We will cover methods for both types.

The Toolkit for PCB Repair

You cannot build a house with just a hammer. And you cannot desolder an IC with just a cheap iron. Here is the list of tools you need.

Essential Tools

1. Soldering Iron: You need an iron with temperature control. It should get to at least 400°C. A wide tip (chisel tip) is better than a pointy tip. A wide tip holds more heat.
2. Solder Sucker (Desoldering Pump): This tool uses a spring and a vacuum to suck up hot solder. It makes a “click” sound. It is great for Through-Hole parts.
3. Solder Wick (Desoldering Braid): This is a copper rope. It acts like a sponge for liquid metal. It cleans the pads very well.
4. Flux: This is the most important thing. Flux is a chemical cleaner. It removes the oxide skin from the metal. It makes the solder flow like water. Without flux, desoldering is a nightmare.
5. Hot Air Rework Station: This is a gun that blows very hot air. It is the best tool for SMD components. It heats all the legs at the same time.

specialized Tools (Nice to have)

1. Low Melt Solder (alloy): Brands like Chip Quik make this. It stays liquid for a long time at low temperatures. It is like magic for big chips.
2. Kapton Tape: This is yellow tape that resists high heat. You put it on plastic parts near the IC so you don’t melt them.
3. Tweezers: You need fine, curved tweezers to lift the hot chip.

Safety First

Solder is hot (350°C+). The smoke is bad for you.

• Air: Open a window. Or use a fume extractor fan. Do not breathe the white smoke directly.
• Eyes: Wear glasses. Sometimes, the solder sucker can spit hot solder out.
• Lead: Old boards have lead. Wash your hands after you touch them. Do not eat while working.

Preparation Steps

Do not just turn on the iron and attack the board. You need to prep.

Step 1: Clean the Board
Use 99% Isopropyl Alcohol (IPA) and an old toothbrush. Scrub the pins of the IC. Dust and grease make the solder sticky. Clean solder melts better.

Step 2: Add Fresh Solder
This sounds wrong, right? You want to remove solder, not add it. But, old solder is hard. When you add fresh solder, it mixes with the old stuff. This new mix melts much faster. So, before you desolder, add a little blob of new wire to every pin.

How to Remove Through-Hole ICs (DIP)

We will look at the two best ways to remove through-hole components.

Method A: The Solder Sucker (Pump) Method

This is the standard way. It is cheap and effective.

• Step 1: Prime the Pump. Push the plunger down until it locks into place. Hold it in your left hand.
• Step 2: Heat the Joint. Hold your iron in your right hand. Place the tip on the IC pin. Make sure it touches the pad and the pin.
• Step 3: Wait. Count to two. You want the heat to go all the way through the hole. You will see the solder bubble or turn shiny.
• Step 4: The Swap. This part requires speed. Keep the iron on the pin. Move the plastic tip of the sucker right next to the iron.
• Step 5: Suck. Quickly move the iron away and immediately cover the pin with the sucker tip. Press the button. CLACK! The vacuum pulls the solder out of the hole.
• Step 6: Check. Look at the hole. can you see daylight through it? Take a screwdriver and push the pin gently. Is it loose? If yes, move to the next pin. If no, add more fresh solder and try again.

Method B: The Stainless Steel Needle Method

This is an old trick. It is very safe. You need a hollow stainless steel needle. Solder does not stick to stainless steel.

How to Desolder Surface Mount ICs (SMD)

SMD chips are tricky because you cannot easily access the legs individually. You usually need to heat the whole chip.

Method A: The Hot Air Gun Method (Best for Most Chips)

This is the professional way to desolder surface mount IC.

• Step 1: Shield. Put Kapton tape on nearby plastic connectors. Hot air kills plastic.
• Step 2: Flux. Put a lot of flux gel on all the pins.
• Step 3: Settings. Set your air to 350°C – 380°C. Set the airflow to medium (about 50%). If the air is too fast, you might blow small resistors off the board.
• Step 4: Pre-heat. Don’t aim directly at the chip yet. Warm up the area around it for 10 seconds. This prevents thermal shock.
• Step 5: Heat. Now, aim at the chip. Hold the nozzle 2cm away. Move the hand. Do not stay in one spot. Move in circles around the edges of the IC. You want all legs to reach melting temperature at the same time.
• Step 6: Test. Use tweezers to gently nudge the chip. Does it move? Do not force it.
• Step 7: Lift. When the chip slides easily, grab it with tweezers and lift it straight up.

Method B: The “Flood and Drag” Method (Using Soldering Iron)

If you don’t have hot air, you can use this method for chips with legs on two sides (like SOP-8).

• Step 1: Flood. Put a giant blob of solder on your iron tip.
• Step 2: Bridge. Run the iron along one side of the chip. Connect all the pins together with one big line of molten solder. Do the same on the other side.
• Step 3: Seesaw. Quickly switch your iron back and forth between side A and side B. You are trying to keep both sides hot.
• Step 4: Push. When the solder on both sides is liquid, simply push the chip off the pad with the side of your iron.

Method C: The Chip Quik Method (Low Melt Alloy)

This is the safest method for expensive boards or very large chips with pins on four sides (QFP).

• Step 1: Flux. Apply flux to all pins.
• Step 2: Apply Alloy. This special solder melts at only 60°C. Melt it onto all the pins. Mix it with the old solder.
• Step 3: Wait. Because the melting point is so low, the solder stays liquid for a long time. It does not turn hard immediately.
• Step 4: Remove. Now that all pins are wet and liquid, you can simply wipe the chip off the board with your iron tip or lift it with tweezers. You have plenty of time.
• Step 5: Clean. You must clean this alloy off the pads completely before putting a new chip on.

Cleaning the Pads (The Finish Line)

You got the chip off! Great job. But the board looks messy. The pads are bumpy and dirty. You cannot put a new IC on this. You need to clean the pads.

Step 1: Fresh Solder (Again)
If the old solder is dry and spiky, add a little fresh solder to the pads to make them wet.

Step 2: Use Solder Wick
This is where solder wick shines.

• Put the end of the copper braid on the pads.
• Put your iron on top of the braid.
• The heat goes through the braid. The solder will melt and get sucked up into the copper wires.
• Move the braid slowly across the pads. It acts like a broom.

Crucial Tip: When you are done, lift the iron and the braid at the same time. If you lift the iron first, the braid will cool down instantly. It will stick to the board. If you pull it then, you will rip the pad off. If it sticks, just heat it up again.

Step 3: Alcohol Wash
The board is now sticky from flux. Use Isopropyl Alcohol and a cotton swab or brush. Scrub it until it is shiny and clean.

Troubleshooting Common Problems

Even experts have bad days. Here is what goes wrong and how to fix it.

Problem 1: “The solder won’t melt!”

This is the most common complaint.

• Reason A: Your iron is too weak. You need more power (Watts), not just temperature.
• Reason B: The tip is dirty (oxidized). Solder cannot transfer heat through dirt. Clean your tip on a brass sponge and tin it.
• Reason C: Ground Plane. The pin is connected to a large area of copper inside the board. This copper sucks the heat away. Fix: Use hot air to warm up the whole board first, then use the iron.

Problem 2: “I ripped a pad off.”

This is sad. It happens when you pull the chip before the solder is 100% liquid.

• Fix: You have to repair the trace. You need to follow where the copper line goes. Use a thin wire (jumper wire) to connect the new IC leg to that point. It is ugly, but it works.

Problem 3: “The hole is still clogged.”

You removed the DIP chip, but the hole is full of solder. You cannot put the new chip in.

• Fix: Add more fresh solder to the hole. Try the pump again.
• Fix: Use a stainless steel needle to poke through it while heating.
• Fix: Use a drill? No! Never drill the hole. You will destroy the plating inside the hole. The two sides of the board will lose connection.

Advanced Tips for Professionals

If you want to get really good at PCB repair, try these tips.

Tip 1: Gravity is your friend.
When using hot air or a heater, hold the board upside down (if possible). When the solder melts, gravity helps the chip fall off. This prevents you from pulling too hard.

Tip 2: Listen to the Solder.
That sounds amazing!, but molten flux makes a sizzling sound. When the sizzling stops, the flux is gone. You need to add more flux. Also, molten solder looks like a mirror. Solid solder looks like fog. Watch for the shine.

Tip 3: Pre-heaters.
If you work on motherboards, they are very thick. A small iron is not enough. Pros use a “pre-heater” plate. This warms the whole board to 100°C from the bottom. Then, your top tool only needs to do a little bit of work. This is much safer for the board.

Choosing the Right Temperature

People always ask: “What temperature should I set?”

There is no single answer. It depends on the solder type.

• Leaded Solder (Old): Melts at 183°C. Set iron to 350°C.
• Lead-Free Solder (New/RoHS): Melts at 217°C. Set iron to 380°C or 400°C.

If you are not sure, start at 350°C. If it takes longer than 3 seconds to melt, go up to 375°C. Do not go above 450°C unless you are very fast, or you will burn the glue holding the pads.

Conclusion

Learning how to desolder IC from PCB is like learning to ride a bike. You will wobble at first. You might fall. You might ruin a practice board or two. That is normal.

Do not start with your expensive Macbook. Go to a recycling center. Get an old broken router or radio. Practice removing every single chip on that board. Try the pump. Try the wick. Try the hot air. Learn how the solder flows.

Once you understand the feeling of the metal melting, you will gain confidence. You will realize that electronics are not magic black boxes. They are just parts connected by metal. And you have the power to change those parts.

Remember the golden rules:

1. Don’t force it.
2. Use flux.
3. Keep it clean.

Now, you are ready. Go fix something!

FAQ

Blog Recommendation