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I am not very experienced with soldering. I have a basic soldering iron with a new tip, and a third hand.

Last time I tried soldering wires to a ble chip that looked like this, I ruined two chips in the process and gave up. Those were not cheap.

Now I want to solder this QFN chip but I want to have the right tools and skills for the job.

Perhaps I don't even need to solder, all I want is to connect some of the pins of the chip to a bread board. If there is another way to do that without soldering, I would prefer that.

I am a novice in this area. Any help, guidelines or reference to tutorials for beginners would be much appreciated.

I just want to know what is the best way, that is relatively safe (so I won't destroy the chip), to get it on a bread board.

Thanks!

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    \$\begingroup\$ A QFN socket is possible, but extremely expensive. You need to get into reflow soldering. Buy a cheap reflow workstation (ATTEN-858D+ is good) and learn to use it. \$\endgroup\$
    – Majenko
    Dec 11, 2014 at 15:52
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    \$\begingroup\$ More importantly, don't waste your time putting a Wifi part on a breadboard. The parasitic capacitance will render it nearly, if not, unusable. It requires an antenna, and a controlled impedance trace to it. \$\endgroup\$
    – Matt Young
    Dec 11, 2014 at 15:53
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    \$\begingroup\$ Also, for that chip, you need to lay the PCB out properly. Best to buy a pre-built module (Adafruit sell them IIRC). \$\endgroup\$
    – Majenko
    Dec 11, 2014 at 15:53
  • \$\begingroup\$ Buy a Spark Core. Preorder a Photon. Neither is quite the same as that IC but both have advantages and the Photon is arguably superior and cheaper than you will pay. spark.io \$\endgroup\$
    – Russell McMahon ♦
    Dec 11, 2014 at 16:06
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    \$\begingroup\$ Agree with Majenko - Check out adafruit.com/product/1469. What I did with this board is remove the components I didn't need (level shifter and LEDs mainly) and then connect it to a breadboard (and then to a PIC micro). It's sitting beside me here! \$\endgroup\$
    – carveone
    Dec 11, 2014 at 16:21

4 Answers 4

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I would suggest to buy a QFN to DIP adapter, something like this.

enter image description here

Then, you can use air reflow or solder with an iron. I solder all 0.5mm pitch components, such as CPLDs or FPGAs with a good soldering iron using a small (thin) tip.

However, it might not fit well into your breadboard since there are two parallel rows on each side. What I usually do is solder DIP female pin headers

enter image description here

on this board and then use wires to connect it to the bread brad.

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    \$\begingroup\$ This solution is easy in terms of soldering, but you need to pay attention at the comments to your question above such as @mattyoung about layout and RF interference that might potentially make the board not usable. Depending on you budget, I would suggest designing your own PCB board or find one that will accommodate your circuit. \$\endgroup\$
    – Nazar
    Dec 11, 2014 at 16:59
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    \$\begingroup\$ How do these adapters help? The question was about how to solder the chip. Whether you solder to your own board or to this adapter, you still have the same problem. \$\endgroup\$
    – Olin Lathrop
    Dec 11, 2014 at 17:41
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    \$\begingroup\$ @Naz That's not just what you understood, that was literally his question. "I just want to know what is the best way, that is relatively safe (so I won't destroy the chip), to get it on a bread board." \$\endgroup\$
    – ACD
    Dec 11, 2014 at 18:43
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    \$\begingroup\$ But either way, he still has to solder the chip to a board. Whether that is a adapter board or his own board makes no difference to the difficulty or the procedure. The hard part here is soldering the chip onto a board, something that is out of reach if the only tool you have is a ordinary soldering iron. You make it sound a lot simpler than it is by glossing over the real problem. \$\endgroup\$
    – Olin Lathrop
    Dec 11, 2014 at 19:17
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    \$\begingroup\$ I've successfully soldered these packages with just a thin tip. You do need a magnifying glass if you don't have good vision, and a steady hand. I place a solder pillow on one corner, hold the iron on the pad until it flows, align the chip with tweezers and then remove heat. Now the chip is aligned and stuck there. Then you dump a lot of flux onto each pad, touch the iron to the outside of each pad and then use thin solder to touch the pad as close as you can to the IC and you'll attach each pin. Tedious and unreliable, but possible. \$\endgroup\$
    – ACD
    Dec 11, 2014 at 22:05
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Short answer: You can't with your equipment.

That's a .5 mm (20 mil) QFN. Trying to solder that with a soldering iron will only make a mess. Ideally you use solder paste, a stencil, accurate automated placement, and a reflow oven.

I have soldered similar chips with a hot air station and some care. Use a soldering iron to put a bead of solder on all the pads. You want the amount of solder on each pad to be as even as possible, but there should be a clear "bulge" of solder on each pad.

Then liberally apply paste flux and very carefully place the chip correctly over the pads. Use a magifying light or similar to make sure the chip is aligned close to right. It doesn't have to be exact, but you don't want any part of a pin over a adjacent pad. This step is tricky, especially since it's hard to move the chip the tiny amounts required for final alignment.

Next apply hot air. I usually use around 700°F, but only the minimum air flow you need. Try to heat the chip as evenly as possible. After a few seconds, you will see the solder melt, at least on one side, then hopefully all sides a second or two later. At that point the surface tension of the molten solder will align the chip nicely. You will probably see it move. Leave heat on for another few seconds just to make sure everything is really melted, then remove heat and let cool. This whole step should take maybe 10 seconds, 20 tops.

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    \$\begingroup\$ Preheating board underside with hot air can help - depending on what else is being done. \$\endgroup\$
    – Russell McMahon ♦
    Dec 11, 2014 at 16:04
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The CC3200 is available as a module too, with integrated crystal and all the support components. I highly, highly recommend that you use that. It's not easier to solder, but it will have a booster pack available which you can just plug into your main PCBA.

Or even easier, just buy the CC3200 Launchpad and use it for the basis of your product.

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Check out this product from Schmartboard. It is a special breakout board made for your specific IC package, and all it takes is a fine-tipped soldering iron to make the connections.

Basically, it has troughs preloaded with solder. You place the chip, and then (with the soldering iron) you push the solder towards the IC, where it makes contact to the pads underneath.

I've used them before, and it's a little tricky at first. Expect to throw away the first IC you try, although you may not actually have to :)

However, as @MattYoung said in a comment, trying to get rf working through wires and a breadboard is bound to be frustrating.

Good luck!

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