SMD Soldering

Thread Starter

Hymie

Joined Mar 30, 2018
1,002
I recently posted a question seeking a surface-mount adapter board for an IC (to allow through-hole solder connection).

I’ve now received the adapter board and I’m seeking advice on soldering the surface mount IC to the board – which I’ve never done before.

The surface mount adapter board has the solder pads pre-tinned. I’m planning to glue the IC in position and then use a heat gun (with a fine nozzle) to apply sufficient heat to each pin to make the solder connection with the pre-tinned pads. To me this seems a better option than using a soldering iron which is likely to result in solder bridges between pins.

Any advice/tips on soldering the surface-mount IC to the board would be gratefully received.
 

Yaakov

Joined Jan 27, 2019
3,737
You are taking about “reflow” and you will need to put solder on the pads. Glue is not a good idea, hold the part with tweezers. You will also need flux.

There are many videos on YouTube which can give you an idea what to expect.
 

MrChips

Joined Oct 2, 2009
24,609
You can hand solder SMD using a soldering iron with a fine tip and fine diameter solder.

You don't need glue.

Create a tiny solder blob on one corner pad (better if it is away from the IC footprint itself.
Position the IC over the footprint. Apply heat from the soldering iron and allow the solder blob to melt and secure that pin.

Go around the IC and solder all the other pins. You don't need a lot of solder. Use a flux dispensing pen to help the solder to flow.

1625779236702.png
 

SamR

Joined Mar 19, 2019
3,606
Helps to tin the pad on the adaptor with a very light coat of solder. If too much use wick to remove excess. I like to use paste flux on the adaptor board pads. Paste the tinned pad and put the chip on the pad and the paste helps to hold it in place. Adjust as necessary. Then solder one corner leg only. The chip tends to move a bit and will need fine adjustment and pressing down if it kicks up when soldered. Then solder the opposing corner and wipe the iron down across the legs. Repeat on the other side and yer done. Check to make sure no solder bridged between legs and if it did a simple swipe of the hot iron tip between legs will open it. Clean with IPA as needed. Similar procedure for 3 leg transistor adaptors.
 

nsaspook

Joined Aug 27, 2009
8,898
Don't be afraid to sweep blob solder. Solder wick and flux are your friends. It's very easy to clean up solder bridges with a fine tip iron and wick. The trick to success is cleanliness of the tip, cleanliness of the wick, cleanliness of the PCB, cleanliness of the leads and cleanliness in general.

 
Top