Onkyo A-SV610PRO, Service Manual

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Techniques for Replacing Surface Mount (SMD) IC’s
Every technician has had to replace a surface mount device (SMD) IC at one time or
another. How do you successfully remove and replace a surface mount IC? By successful
I mean removing the defective IC without damaging the delicate traces on the PC board
and aligning and soldering the replacement IC in place. Here are a few techniques you
can use to remove and replace a surface mount IC.
IC Removal
Desoldering Braid: Desoldering braid is a specially treated fine copper braid which
draws molten solder up into the braid where it solidifies. Desoldering braid is usually
sold on a small dispenser reel. The best way to use desoldering braid is to press the tip of
a hot iron onto a short length of braid that is placed over the joint to be de-soldered.
The iron will subsequently melt the solder, which will be drawn up into the braid. If the
desoldering braid is not drawing the solder but just seems to push it around the board add
a small amount of solder flux to the braid and try it again. After most of the solder has
been wicked use a dental pick or similar object and lift the IC pins while heating them
with a hot soldering iron.
Razor Knife Technique: Using a sharp razor knife, align the blade close to the body of
the IC and on the top of the row of pins. Applying a constant downward force cut the
pins away from the body of the IC. You will hear a distinct clicking sound as you severe
the pins.
Work your way down the row. Repeat this process for each row of pins until the body of
the IC is free from any pins and can be lifted away from the board. By cutting and
removing the body of the IC you are removing the “heat sink” that draws the heat from
the IC pins when you try to remove the IC with desoldering braid alone. Next, use
desoldering braid and a hot soldering iron to remove the remaining IC pins from the
board. This method allows you to remove the IC quickly and without damaging the PC