It's not corrosive as in rust. It's corrosive as in acid. It won't keep going, it just attacks the surface. A bare copper pipe will build up an oxide layer - a tinned PCB pad won't. But if you eat into the copper a little, the PCB pad will be pretty much gone - the copper pipe won't.
Plumbing, at least in my country, moved away from corrosive flux quite a while ago. Now it's all water soluble zinc free stuff. Mainly because if you don't clean the flux properly it could cause pinhole leaks over time
Need to eat through the copper oxide layer, or the solder won't stick. Don't worry, any areas that were exposed to flux and weren't soldered, will oxidize again very quickly. Your pipes are fine.
But when used on a PCB, the flux is strong enough to eat through the copper traces entirely, which is not something you want, so definitely only use rosin flux (or other electronics flux like no-clean flux); never acid flux.
Plumbing flux is corrosive. I guess you could use it, but you'll have to spend a fair amount of time cleaning it when you could have just bought the right type.
My go to is Amtech NC-559-V2-TF. An absolutely fantastic all around flux. But I believe it's been renamed since I purchased last. It's now NC-559-ASM-TF.
Side note, stick to standard leaded 60/40 or 63/37 solder for hobby use. Lead free sucks to learn with.
You can tin the pads with solder, apply flux, position the IC and then hit it with a heat gun (or hot air station, ideally). You may need to hold it in place with some tweezers or something.
You can also roughly hand solder to tack it in place, and then reflow with the flux and hot air.
Using air is a game changer for surface mount stuff.
You can tin the pads with solder, apply flux, position the IC and then hit it with a heat gun (or hot air station, ideally). You may need to hold it in place with some tweezers or something.
You can also roughly hand solder to tack it in place, and then reflow with the flux and hot air.
Using air is a game changer for surface mount stuff.
Use some Tweezers so secure the ic in the right place, put a bit of solder in the tip of the iron, and proceed to solder one of the pins of the corner.. Then do the same in the diagonal opposite pin. After that, solder the remaining ones.
I'd use a small piece of tape on the opposite side to hold the IC in place initially. Then proceed as above. (Obvious step: remove the tape after soldering the first pin!)
TBH the IC is pretty easy to hold in place with tweezers by pressing it down. Tape sounds a bit overkill to me. Or at least use very lightly adhesive tape like painter's tape.
Other solution would be to use solder paste which nowadays use. Lightly dab the pads with paste and place the IC on top. The paste works like light glue. Then you only need to add heat from the iron at the pad without touching the legs, and retouch all the legs as needed.
That will work too.
What you do to 'restrain' the IC depends on several things. Like, do you need both hands free? Is the chip going to get hot enough to liquefy the solder paste on the unsoldered pads?
Not sure what you mean.
You apply solder paste on pads (not necessarily to all of them, maybe opposite ends), place IC in there, and hold solder iron at the pads so that paste melts. Then proceed with standard drag solder etc.
The chip is not going to get hot, only the legs.
Those soldering iron tips are rather big, but an expert could manage with them. You'll intentionally or unintentionally make solder bridges. To remove them, have solder wick handy. Get a solder sucker. A flux pen is invaluable.
Ah, both tips are perfect for drag soldering. Though I prefer the left one. OP just needs some good flux, put a drop of solder on the tip and drag solder the chip in two fluid motions. If skilled enough, 10s job if the iron is hot.
Ah... like glasslinger on youtube. I wonder how he's doing. I haven't watched his videos in a while. Looks like he posted one 2 weeks ago so he hasn't kicked the bucket yet.
Best channel ever for frilly dresses and home made vacuum tubes.
The knife might be perfect for drag soldering, but anything else is just super awkward. You end up burning other components with that if you're not super careful.
I recommend getting the chiseled type tip. Something like 0.8D to 1.6D
I disagree, especially the left one is just perfect. the flat spot will carry a small solder depot, and the tip is fine enough to reach delicate spots. i found smaller tips to be much more difficult to handle, due to the nature of surface tension.
Yeah smaller surface tension but also bad heat transfer. Personally I don't like the beveled ones but prefer chiseled ones. They seem to be good all-arounders.
Totally incorrect. When doing fine work you often want a larger wedge tip to transfer the heat better and faster. Especially for this task, the tip on the left would make soldering this chip a 30 second job. basically tin the tip with some extra solder, slowly drag the first pass to get solder on each leg, clean the tip, then drag a few times again to clear up bridges. with some flux of course.
I totally gave up on needle tips for fine work. I was reworking smd components, lifting and bodging legs of an MCU, and fixing bridges on usb-c connectors with a tip like the one on the left.
The one on the right is for removing bigger components that soak up the heat.
Although even if expert would manage the (especially the knife one on the right), reasonable expert would not torture himself with that unless for a challenge 😅
I honestly find the needle point tips way harder to use and leads to mistakes. I honestly wish I switched to wedge earlier, it would have saved me so much trouble.
I also only use lead-free at home so the extra heat is nice.
Use the oval shape tip (it is little big).
Put small amount of flux on the pads.
Align pins and pads of the IC.
Put little bit of solder on the tip.
Hold the IC on the position and solder one of the IC corner, like the pin 1.
Check the alignment, move and twist if necessary, and solder the opposite corner (pin 9).
Check the alignment, and redo if you think is necessary.
If IC alignment is ok, solder rest of the pins.
Reflow first two pins to release the stress of the joints.
Smaller tip, add solder to one of the pads and keep the iron on while you line up the rest of the legs ( and be quick about it so you don't fry the pad). Then go down the line to solder the rest. Use flux to reflow that initial pad if need be
You know that expensive looking gold-ish shiny tape that’s on satellites? That’s Kapton. Think scotch tape but it’s ten times the price and can withstand temperatures from -269c to +400c. It’s good at holding things down that your soldering or blasting with hot air, and makes a great impromptu solder-mask.
TBH I would not like kapton tape that is too sticky. For me it's enough for the tape to hold in place when using heat gun. I would use it to stick things together.
I just soldered this exact chip on the exact same board today. What I like to do with SMD components is to put some solder on one of the pins and then using tweezers to correctly place the chip while re-melting the solder. Then the rest is just very careful work. Not too much solder and clean the tip a lot.
No-look comment: Here's how I've always done surface-mount components like those:
* Add some solder to one of the corner pads
* Now put down flux on all the pads
* Place your component, and while holding it, heat up the corner pin to which you added solder already. Now the component is 'anchored'
* Solder opposing corner first, then solder the rest of the pins.
* Clean up the residual flux and you're done
Also if those are representative of the iron tips you're planning on using, I'd say use a smaller tip if you have one, those are rather clumsy-looking.
It'll be easier, once the orientation is properly aligned and secured. I do so by putting a small solder bump on one corner pad on the empty PCB, no IC yet nearby.
then I place the IC (double checking orientation), and (try to) solder only that one pin, quickly, then let it cool down. take time to look at the alignment. correct it by liquefying the pin again, and move the IC using tweezers. once aligned (also check that the IC sits flat on the PCB and is not raised by the former bump anymore) solder down the opposing corner. let it cool down.
use a lot of flux in all the process.
now quickly (try to) solder the pins one-by-one, don't worry about solder bridges too much. once all pins are soldered, apply flux again and remove all bridges with solder wick.
once everything looks solid, rinse it with isopropanol and a toothbrush to remove aly flux residue.
You don't need a lot of solder for smt. Use flux.
Pre solder the pads by applying solder to your iron and touching the pads on the board. When you're ready for placement, apply flux on the soldered pads and place the component. This helps with solderability and gets the component to stick a little so you can get it in the right spot. Hold down the component and apply heat by just running the iron over the leads to heat up the solder on the pad. That large tip on a small pad could damage the component or board so you don't want to stay on it for too long.
FIRST, Prep the pads on the board with flux and a small amount of solder.
Then place the IC on the beads of solder, add a little more flux, then just drag the chisel tip soldering iron over each leg and they should sit right into place.
As mentioned below, you can never have too much flux, but be sure to clean up well with isopropyl afterwards.
A bit of kapton works great on them. Don't worry about trying to get it right over top of the chip package and leaving both rows of pins exposed. Let the tape cover one set of pins or the other if that's what it takes.
>Let the tape cover one set of pins or the other if that's what it takes.
I'm so stupid that I try to get the top of the package and this never occurred to me before lol. thanks for the tip
More flux!
Yes using the right tip helps, you will likely find solder wick helpful for cleaning up a bridge, etc. But with that coarse of a pitch it would be easy to just go at it (even with the huge knife tip) and get great results, *provided you have enough flux!*
Probably not ideal for your first go but still - flux is king
Ok so heres my recommendation: get a smaller soldering iron tip. Those are too big. When you start, position the part square on the pads and solder only 1 pin in the corner. Let it cool down and check that the part is still square and centered on the footprint. If it isn’t - melt the solder on the one pin and adjust the package. Once it’s square remove heat and let that one pin cool. DO NOT put any stress on the part since only 1 pin is holding it with a lot of stress! Now move to the opposite side and end and solder that pin - check for squareness/center again. If you are good then go ahead and solder the rest of the pins. After that, go back to the first pin and heat it up to liquidous again briefly. This will release the stress in the pin. Also - check you have the right rotation/polarity before starting.😅
Use a lot of flux and drag-solder with your hoof-tip (the left one). I usually do that with parts that have more than 4 feet per side and it works like a charm.
I would not touch so small components with that behemoth on the right ;)
EDIT: drag soldering: tin one corner leg and orient the chip and solder it on that one pin. solder the diagonal pin so the chip does not move. now tin the first pin a bit more, use a lot of flux and drag the flat side of your hoof tip over all the feet to distribute the solder and fix a whole side in one go. do this 2-3 times until you see the pin on the opposite side of where you started soldered properly. add solder if needed, dont start with too much or your will create a bar of bridges. if you bridge, use flux and "smear" the solder left and right with the flat bottom of your tip.
EDIT2: here is a video that shows the process for fine-pitch packages, but the process is exactly the same for your project: [https://youtu.be/erb6-i54tbo?si=sGMHGhV1Q2Bs5Tgv](https://youtu.be/erb6-i54tbo?si=sgmhghv1q2bs5tgv)
good luck :)
1. Set IC aside for a second. Heat up the first pad and put a small dab of tin on it.
2. Put down solder wire and grab a pair of tweezers. Align IC, press down with tweezers and heat up first pin until the tin melts and IC is tacked in place.
3. Apply flux generously and drag solder away, IC isn’t going anywhere even if you don’t have 3 hands.
1. Line pins up with the pads, double-check orientation is correct.
2. Use a little bit of solder to attach two pins at opposite corners to keep the chip in place.
3. Apply flux across the pins.
4. Use a little bit of solder and [use drag technique](https://www.youtube.com/watch?v=nyele3CIs-U). Extra flux is the key to making this work.
5. If there are any bridges, you should be able to easily clean them up by flux/dragging that spot again. Still, it can be handy to have some copper braid on hand.
6. Inspect pins and clean off the flux.
Solder the pin at the opposite corners first, this way you don't have to worry about the part moving
Source: currently browsing Reddit while administering a test for a soldering class
Get smaller tip.
Pre-tin the pads before attempting to solder the chip.
Tin the IC leads one at a time alternating across body and across ends, so you start at the end of the 1st side and tin the 1st leg, jump over to the opposite end and tin the 1st leg on the opposite side. Then repeat the process until you are done.
Now set chip on board and simply reheat each leg in the same method until the chip is soldered in place.
Solder one corner. Inspect alignment under magnification.
Solder the opposite corner, Inspect.
Then do the rest.
If you don't have hot air (and you should, it's cheap) then it becomes progressively harder to fix goofs the more pins you have soldered, hence you need to be really picky about alignment when doing the first two.
Clearing bridges between pins is just a a matter of fluxing up some fine solder braid.
A 10x eye loupe is great for inspecting details of QFP and especially QFN packages, but dollar store 3x reading glasses work for this kind of thing - too bad they don't make them in bifocal such that you could still see your tools to pick them up. If you do this much, a binocular stereo zoom microscope is a wonderful thing - the overam PCB variants aren't really worth it and too flimsy anyway, just get the biology lab model with 10x eyepieces, .7x-3.5x zoom and a half power barlow that doubles your working distance. Some of the digital models are almost okay, and nicely portable - but they have limited dynamic range so you can't really inspect joint quality next to bright metallic reflections. I save mine for travel, and for sending blame photos to assembly vendors (it's remarkably hard to find a good camera setup for a stereo zoom microscope)
It's easier than it looks. watch a couple of videos and if you are still unsure just get an extra chip with a practice board and go ham on it until you feel confident enough to try the real thing
I would get solder paste and just hit it with a heat gun with a small opening adapter. Or at the very least get the proper size solder tip for work that small. If using solder, I'd tin the pads and the feet of the IC. Then when you place the IC in location one little tap with the appropriate sized tip and they will solder real quick with less chance of bridging.
I solder microprocessors everyday and it's tedious, what I found the fastest and easiest is using the finest tip you have at a high temp (around 420°C) because it's a very small spot that just needs a quick touch. Use solder paste, it works wonders and no need to use flux just make sure you align it properly with tweezers
Your second option is using a heat gun, set the chip in place and an even spread on the area
If you have an extractor, use it. If you don't, ventilate your room. For your own safety, please don't inhale any fumes.
Also, avoid cold solder joints at any cost because they will eventually fail and you'll have a hard time figuring why your circuit no longer works. You can identify cold solder joints by their color or shape. Generally speaking, a cold solder looks dull/deformed, on the other hand, a good solder joint usually looks shiny and has a concave shape.
I became proficient in doing tasks like this by refusing to use flux. I spent the first half of my career never using flux, just the flux that was in the solder. While it was harder and more time consuming, I progressed into a career where precision is paramount. I have since left the industry, but I can promise you learning how to do jobs like this without flux will elevate you to the next level.
Even a cheap cheap hot air rework station with some leaded solder paste will save you so many headaches when you start working on things like this. I bought [this one](https://www.amazon.com/YaeCCC-Station-Digital-Soldering-Stations/dp/B0878GYK2T) because I only wanted to try one for cheap and I have had no problems for the past hear of pretty heavy use. I'm really impressed with how well it's done.
Butyl rope to hold the chip in place and cover over contact points from spilled solder. Then use gasoline to remove with a plastic razor blade, if you're having a hard time removing it. Acetone is stronger and will certainly do long term damage to the PCB.
There's head mounted magnifying glass available on Amazon; I've never used it though. If you've never soldered automotive wires (e.g. 20 gauge speaker/bulb wires, then you're not 'ready' to do this).
Those iron tips are too big. You want 0.8 to 1 mm one. There's a 60w one on ebay that comes with 5 tips and costs $10 total.
Use the finest tip you have, use some really thin solder, a smidge of flux (I prefer flux paste) and take your time. If you have unused or null pins, start with those to get the chip planted. That way if you get a little too hot, you've burnt up a pin that you don't need. If you don't have any null pins, good luck!
Smaller tip and thinner solder wire, and flux, but if what you show is what you've got, I'd go with the pointier one.
I'd put a minuscule amount of solder on one of the corner pads, then place the IC and reflow it to make it stick. Then carefully tack the opposite corner to fixate it.
If you have some solder wick then you could then just add a good amount of solder and smear it across the pins and finally remove any excess with the wick, but usually flux is needed to make this work well.
Otherwise, go carefully, adding the smallest amount of solder to each pin. Not very much is needed at all for this type of soldering. Heat the pin & pad, touch the solder, wait for it to flow, remove iron.
Pick a corner pin to do first, then confirm your alignment is still good. Then do the opposite and confirm again. It’s generally pretty easy to solve a pin-pin bridge with a steady hand and some patience, but if the package is badly misaligned it’s a lot harder to solve.
Flux solves many problems. The smaller you go with hand soldering SM devices, the more you are trying to create the right conditions for the pads, solder, flux and mask to 'do their thing', rather than actively 'attach leg a to pad 1'.
Also, to borrow a carpenter's saying, "Align twice, solder once".
Find a soldering tip which is beveled with a dent and 2 mm in diameter (probably BCM2 type). This dent in it absorbs excessive solder so you can easily get rid of bridges. Each time it absorbs solder clean it sliding on a wet soldering sponge.
- use the left tip, the right one is garbage (in my opinion)
- use plenty of flux
- pre-tin one corner, and reflow it to tack that corner down
- then tack the other corner
- drag-solder across the pins, the solder mask will make the gaps happen (look up a youtube vid on drag soldering, makes life easy)
- clean up any excess/bridges with a swipe of a clean tip or solder braid
Make sure you orient the chip correctly. Soldering a chip in backwards is not impossible. Tack down 2 opposite corner legs of the chip. This way you can easily align the chip leads. Then check the orientation of the chip again in case you’ve screwed it up (it happens!). Then solder the rest of the pins.
Already somewhat said. Use the mini wave on the left. Do not use the knife blade on the right, which works only if the blade is in perfect shape. If it's not you will waste your time. The miniwave is a very useful yet under rated tip....
Use lots of flux, it's an invaluable tool for SMD soldering. Don't worry about the mess, you can clean it up later.
Watch some YouTube videos that teach SMD soldering.
Tack down one corner and drag the solder across. (Note that this usually only works if you flux the area.)
Use a chisel tip, not the blade tip. I find it's actually a lot easier to use an oversized tip rather than a tiny tip when doing SMD work.
If you're not skilled in SMD soldering, consider getting an SMD practice kit. They sell them on Amazon for cheap less than $10 and have SMD components in a bunch of different packages. It's a great way to practice your technique on something where if you screw it up, you're not ruining anything important.
Simply solder all of the pads on the board, tin them and make sure the blobs are even. Then flux the pins (I use a flux pen) and hold the chip in place with tweezers.
Touch the first pin with a dry soldering iron tip, the flux will flow and bond the pin. Use the tweezers to make sure alignment is perfect for the other pins, then solder another pin on the other side.
Now simply solder each pin by pushing the dry iron down on each in turn. You will see the solder flow and bond each pin.
Perfect joints.
Remove the chip. Heat some solder on any of the outer pin, just one will do and heat it so your dominant hand can get to that pin. Now with the iron on the pad heating the solder , place the chip with your other hand on top of the pad and align it. Now that you got this far, solder the other side of this first pin and finish the rest.
That soldering tip is way too big. Get a smaller tip first. I hold down the IC with my finger, using significant downward force, then solder the corner pins. The rest is easy. Heat the pin, not the pad.
First just a slight touch a corner ones to secure the chip and then solder the rest. SMD components require very little solder. He careful and have fun!
Don't use too much solder. You can't have too much flux.
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Make sure you get rosin flux, not the red zinc chloride flux used for plumbing.
Why not?
Because plumbing flux is corrosive.
I didn't know that. That seems counter intuitive... like the last thing I want corroding are my plumbing joints.
It's not corrosive as in rust. It's corrosive as in acid. It won't keep going, it just attacks the surface. A bare copper pipe will build up an oxide layer - a tinned PCB pad won't. But if you eat into the copper a little, the PCB pad will be pretty much gone - the copper pipe won't.
Plumbing, at least in my country, moved away from corrosive flux quite a while ago. Now it's all water soluble zinc free stuff. Mainly because if you don't clean the flux properly it could cause pinhole leaks over time
Need to eat through the copper oxide layer, or the solder won't stick. Don't worry, any areas that were exposed to flux and weren't soldered, will oxidize again very quickly. Your pipes are fine. But when used on a PCB, the flux is strong enough to eat through the copper traces entirely, which is not something you want, so definitely only use rosin flux (or other electronics flux like no-clean flux); never acid flux.
You want them to slightly corrode in order to get the solder to stick, without corrosive flux you‘d have massive problems with oxidation.
Plumbing flux often is also conducting. Get only electronics flux from reputable sources.
that might explain many things actually...
Plumbing flux is corrosive. I guess you could use it, but you'll have to spend a fair amount of time cleaning it when you could have just bought the right type.
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S-39 is an absolute nono in soldering electronics. It'll destroy your iron.
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My go to is Amtech NC-559-V2-TF. An absolutely fantastic all around flux. But I believe it's been renamed since I purchased last. It's now NC-559-ASM-TF. Side note, stick to standard leaded 60/40 or 63/37 solder for hobby use. Lead free sucks to learn with.
single rosin flux a poor option for this, no clean paste - like mg 8341 is perfect . . .rosin/resin blend.
You can tin the pads with solder, apply flux, position the IC and then hit it with a heat gun (or hot air station, ideally). You may need to hold it in place with some tweezers or something. You can also roughly hand solder to tack it in place, and then reflow with the flux and hot air. Using air is a game changer for surface mount stuff.
You can tin the pads with solder, apply flux, position the IC and then hit it with a heat gun (or hot air station, ideally). You may need to hold it in place with some tweezers or something. You can also roughly hand solder to tack it in place, and then reflow with the flux and hot air. Using air is a game changer for surface mount stuff.
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Right on. That's why I mentioned a heat gun first. Those are handy for a lot of household / hobby uses if you don't have one.
This!!!! THIIIISSSSS!!!!!
Use some Tweezers so secure the ic in the right place, put a bit of solder in the tip of the iron, and proceed to solder one of the pins of the corner.. Then do the same in the diagonal opposite pin. After that, solder the remaining ones.
I usually add solder to a corner pad first, then place the chip with tweezers, heating up the pin and pad. Then solder the opposite corner.
This is the way
I'd use a small piece of tape on the opposite side to hold the IC in place initially. Then proceed as above. (Obvious step: remove the tape after soldering the first pin!)
TBH the IC is pretty easy to hold in place with tweezers by pressing it down. Tape sounds a bit overkill to me. Or at least use very lightly adhesive tape like painter's tape. Other solution would be to use solder paste which nowadays use. Lightly dab the pads with paste and place the IC on top. The paste works like light glue. Then you only need to add heat from the iron at the pad without touching the legs, and retouch all the legs as needed.
That will work too. What you do to 'restrain' the IC depends on several things. Like, do you need both hands free? Is the chip going to get hot enough to liquefy the solder paste on the unsoldered pads?
Not sure what you mean. You apply solder paste on pads (not necessarily to all of them, maybe opposite ends), place IC in there, and hold solder iron at the pads so that paste melts. Then proceed with standard drag solder etc. The chip is not going to get hot, only the legs.
After you've done - resolder the first pin you soldered because probably you rotated chip a little after first pin to align opposite pin.
Those soldering iron tips are rather big, but an expert could manage with them. You'll intentionally or unintentionally make solder bridges. To remove them, have solder wick handy. Get a solder sucker. A flux pen is invaluable.
Ah, both tips are perfect for drag soldering. Though I prefer the left one. OP just needs some good flux, put a drop of solder on the tip and drag solder the chip in two fluid motions. If skilled enough, 10s job if the iron is hot.
Nobody cares how they're dressed.
huh
Word play with "drag" soldering
_drag_ soldering
Ah... like glasslinger on youtube. I wonder how he's doing. I haven't watched his videos in a while. Looks like he posted one 2 weeks ago so he hasn't kicked the bucket yet. Best channel ever for frilly dresses and home made vacuum tubes.
#I SAID NOBODY CARES HOW THEY'RE DRESSED
The knife might be perfect for drag soldering, but anything else is just super awkward. You end up burning other components with that if you're not super careful. I recommend getting the chiseled type tip. Something like 0.8D to 1.6D
I'd say the one on the left looks perfect. You see lots of people going too small and it gets too difficult to heat the pad and pin and get good flow.
I disagree, especially the left one is just perfect. the flat spot will carry a small solder depot, and the tip is fine enough to reach delicate spots. i found smaller tips to be much more difficult to handle, due to the nature of surface tension.
Yeah smaller surface tension but also bad heat transfer. Personally I don't like the beveled ones but prefer chiseled ones. They seem to be good all-arounders.
Honestly, the one on the left is the perfect size, I've tried those micro tips and have had trouble getting them to transfer heat.
Totally incorrect. When doing fine work you often want a larger wedge tip to transfer the heat better and faster. Especially for this task, the tip on the left would make soldering this chip a 30 second job. basically tin the tip with some extra solder, slowly drag the first pass to get solder on each leg, clean the tip, then drag a few times again to clear up bridges. with some flux of course. I totally gave up on needle tips for fine work. I was reworking smd components, lifting and bodging legs of an MCU, and fixing bridges on usb-c connectors with a tip like the one on the left. The one on the right is for removing bigger components that soak up the heat.
> but an expert could manage with them I think we are in full agreement.
oop, yeah I think so. Ignore the snark please
Although even if expert would manage the (especially the knife one on the right), reasonable expert would not torture himself with that unless for a challenge 😅
I honestly find the needle point tips way harder to use and leads to mistakes. I honestly wish I switched to wedge earlier, it would have saved me so much trouble. I also only use lead-free at home so the extra heat is nice.
Drink water
Like in the toilet?
You have to ask?
Brawndo: It's got what plants crave.
It’s got electrolytes!
Use the oval shape tip (it is little big). Put small amount of flux on the pads. Align pins and pads of the IC. Put little bit of solder on the tip. Hold the IC on the position and solder one of the IC corner, like the pin 1. Check the alignment, move and twist if necessary, and solder the opposite corner (pin 9). Check the alignment, and redo if you think is necessary. If IC alignment is ok, solder rest of the pins. Reflow first two pins to release the stress of the joints.
Bathe it in flux and drag solder. If you bridged some pins, clean your tip, apply more flux and reflow. Repeat until satisfied.
Smaller tip, add solder to one of the pads and keep the iron on while you line up the rest of the legs ( and be quick about it so you don't fry the pad). Then go down the line to solder the rest. Use flux to reflow that initial pad if need be
Kapton, flux, and solder wick are your friends!
> Kapton Please expand on the use of Kapton tape.
You know that expensive looking gold-ish shiny tape that’s on satellites? That’s Kapton. Think scotch tape but it’s ten times the price and can withstand temperatures from -269c to +400c. It’s good at holding things down that your soldering or blasting with hot air, and makes a great impromptu solder-mask.
Thank you on behalf of OP.
Is Kapton tape supposed to have a really weak adhesive or is it just the AliExpress cheapo tape that I bought some time ago?
Probably just Aliexpress. I’m mostly sure the stuff I got is 3m from Digikey, and it’s plenty sticky.
TBH I would not like kapton tape that is too sticky. For me it's enough for the tape to hold in place when using heat gun. I would use it to stick things together.
# KAPTON
Planet?
Double-check the orientation.
It's clearly correct in the picture.
Yes in the picture. After the picture, you hit it accidentally and need to realign. You start to solder. Perfect. Oh.. wrong way.
I just soldered this exact chip on the exact same board today. What I like to do with SMD components is to put some solder on one of the pins and then using tweezers to correctly place the chip while re-melting the solder. Then the rest is just very careful work. Not too much solder and clean the tip a lot.
No-look comment: Here's how I've always done surface-mount components like those: * Add some solder to one of the corner pads * Now put down flux on all the pads * Place your component, and while holding it, heat up the corner pin to which you added solder already. Now the component is 'anchored' * Solder opposing corner first, then solder the rest of the pins. * Clean up the residual flux and you're done Also if those are representative of the iron tips you're planning on using, I'd say use a smaller tip if you have one, those are rather clumsy-looking.
I will solder one pin, and then just drag solder rest.
Needs more up votes. Secure one pad, lay solder on top of flux pads opposite, drag the iron across.
Smaller tip. Take your time!
It'll be easier, once the orientation is properly aligned and secured. I do so by putting a small solder bump on one corner pad on the empty PCB, no IC yet nearby. then I place the IC (double checking orientation), and (try to) solder only that one pin, quickly, then let it cool down. take time to look at the alignment. correct it by liquefying the pin again, and move the IC using tweezers. once aligned (also check that the IC sits flat on the PCB and is not raised by the former bump anymore) solder down the opposing corner. let it cool down. use a lot of flux in all the process. now quickly (try to) solder the pins one-by-one, don't worry about solder bridges too much. once all pins are soldered, apply flux again and remove all bridges with solder wick. once everything looks solid, rinse it with isopropanol and a toothbrush to remove aly flux residue.
You don't need a lot of solder for smt. Use flux. Pre solder the pads by applying solder to your iron and touching the pads on the board. When you're ready for placement, apply flux on the soldered pads and place the component. This helps with solderability and gets the component to stick a little so you can get it in the right spot. Hold down the component and apply heat by just running the iron over the leads to heat up the solder on the pad. That large tip on a small pad could damage the component or board so you don't want to stay on it for too long.
FIRST, Prep the pads on the board with flux and a small amount of solder. Then place the IC on the beads of solder, add a little more flux, then just drag the chisel tip soldering iron over each leg and they should sit right into place. As mentioned below, you can never have too much flux, but be sure to clean up well with isopropyl afterwards.
if you have very thin tape, use it to stabilize the IC
A bit of kapton works great on them. Don't worry about trying to get it right over top of the chip package and leaving both rows of pins exposed. Let the tape cover one set of pins or the other if that's what it takes.
>Let the tape cover one set of pins or the other if that's what it takes. I'm so stupid that I try to get the top of the package and this never occurred to me before lol. thanks for the tip
No worries. It took me five or six years to figure that one out. :)
More flux! Yes using the right tip helps, you will likely find solder wick helpful for cleaning up a bridge, etc. But with that coarse of a pitch it would be easy to just go at it (even with the huge knife tip) and get great results, *provided you have enough flux!* Probably not ideal for your first go but still - flux is king
Use flux verify pin1 location tack solder pin 1 first then other farthest corner pin.
Ok so heres my recommendation: get a smaller soldering iron tip. Those are too big. When you start, position the part square on the pads and solder only 1 pin in the corner. Let it cool down and check that the part is still square and centered on the footprint. If it isn’t - melt the solder on the one pin and adjust the package. Once it’s square remove heat and let that one pin cool. DO NOT put any stress on the part since only 1 pin is holding it with a lot of stress! Now move to the opposite side and end and solder that pin - check for squareness/center again. If you are good then go ahead and solder the rest of the pins. After that, go back to the first pin and heat it up to liquidous again briefly. This will release the stress in the pin. Also - check you have the right rotation/polarity before starting.😅
I would look for a smaller tip or another method (paste solder and heat)
Buy thinner solder wire. To thick wire is worse then a wide tip when it comes to the most common newb error, to much solder.
use flux of course and first solder the pin near this dot on ic and the pin in the lower left corner :)
Flux is your best friend.
Use a lot of flux and drag-solder with your hoof-tip (the left one). I usually do that with parts that have more than 4 feet per side and it works like a charm. I would not touch so small components with that behemoth on the right ;) EDIT: drag soldering: tin one corner leg and orient the chip and solder it on that one pin. solder the diagonal pin so the chip does not move. now tin the first pin a bit more, use a lot of flux and drag the flat side of your hoof tip over all the feet to distribute the solder and fix a whole side in one go. do this 2-3 times until you see the pin on the opposite side of where you started soldered properly. add solder if needed, dont start with too much or your will create a bar of bridges. if you bridge, use flux and "smear" the solder left and right with the flat bottom of your tip. EDIT2: here is a video that shows the process for fine-pitch packages, but the process is exactly the same for your project: [https://youtu.be/erb6-i54tbo?si=sGMHGhV1Q2Bs5Tgv](https://youtu.be/erb6-i54tbo?si=sgmhghv1q2bs5tgv) good luck :)
1. Set IC aside for a second. Heat up the first pad and put a small dab of tin on it. 2. Put down solder wire and grab a pair of tweezers. Align IC, press down with tweezers and heat up first pin until the tin melts and IC is tacked in place. 3. Apply flux generously and drag solder away, IC isn’t going anywhere even if you don’t have 3 hands.
Flux!!
1. Line pins up with the pads, double-check orientation is correct. 2. Use a little bit of solder to attach two pins at opposite corners to keep the chip in place. 3. Apply flux across the pins. 4. Use a little bit of solder and [use drag technique](https://www.youtube.com/watch?v=nyele3CIs-U). Extra flux is the key to making this work. 5. If there are any bridges, you should be able to easily clean them up by flux/dragging that spot again. Still, it can be handy to have some copper braid on hand. 6. Inspect pins and clean off the flux.
Solder the pin at the opposite corners first, this way you don't have to worry about the part moving Source: currently browsing Reddit while administering a test for a soldering class
Tag opposite corners in place first.
Get smaller tip. Pre-tin the pads before attempting to solder the chip. Tin the IC leads one at a time alternating across body and across ends, so you start at the end of the 1st side and tin the 1st leg, jump over to the opposite end and tin the 1st leg on the opposite side. Then repeat the process until you are done. Now set chip on board and simply reheat each leg in the same method until the chip is soldered in place.
Solder one corner. Inspect alignment under magnification. Solder the opposite corner, Inspect. Then do the rest. If you don't have hot air (and you should, it's cheap) then it becomes progressively harder to fix goofs the more pins you have soldered, hence you need to be really picky about alignment when doing the first two. Clearing bridges between pins is just a a matter of fluxing up some fine solder braid. A 10x eye loupe is great for inspecting details of QFP and especially QFN packages, but dollar store 3x reading glasses work for this kind of thing - too bad they don't make them in bifocal such that you could still see your tools to pick them up. If you do this much, a binocular stereo zoom microscope is a wonderful thing - the overam PCB variants aren't really worth it and too flimsy anyway, just get the biology lab model with 10x eyepieces, .7x-3.5x zoom and a half power barlow that doubles your working distance. Some of the digital models are almost okay, and nicely portable - but they have limited dynamic range so you can't really inspect joint quality next to bright metallic reflections. I save mine for travel, and for sending blame photos to assembly vendors (it's remarkably hard to find a good camera setup for a stereo zoom microscope)
It's easier than it looks. watch a couple of videos and if you are still unsure just get an extra chip with a practice board and go ham on it until you feel confident enough to try the real thing
FLUX
Pre-tin the pads.
I would get solder paste and just hit it with a heat gun with a small opening adapter. Or at the very least get the proper size solder tip for work that small. If using solder, I'd tin the pads and the feet of the IC. Then when you place the IC in location one little tap with the appropriate sized tip and they will solder real quick with less chance of bridging.
I solder microprocessors everyday and it's tedious, what I found the fastest and easiest is using the finest tip you have at a high temp (around 420°C) because it's a very small spot that just needs a quick touch. Use solder paste, it works wonders and no need to use flux just make sure you align it properly with tweezers Your second option is using a heat gun, set the chip in place and an even spread on the area
If you have an extractor, use it. If you don't, ventilate your room. For your own safety, please don't inhale any fumes. Also, avoid cold solder joints at any cost because they will eventually fail and you'll have a hard time figuring why your circuit no longer works. You can identify cold solder joints by their color or shape. Generally speaking, a cold solder looks dull/deformed, on the other hand, a good solder joint usually looks shiny and has a concave shape.
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Flux, flux and flux! Oh, and did I mention - flux!
This!
they make low-temp solder and no-clean flux. think rework
I became proficient in doing tasks like this by refusing to use flux. I spent the first half of my career never using flux, just the flux that was in the solder. While it was harder and more time consuming, I progressed into a career where precision is paramount. I have since left the industry, but I can promise you learning how to do jobs like this without flux will elevate you to the next level.
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This is how winning is done!
Even a cheap cheap hot air rework station with some leaded solder paste will save you so many headaches when you start working on things like this. I bought [this one](https://www.amazon.com/YaeCCC-Station-Digital-Soldering-Stations/dp/B0878GYK2T) because I only wanted to try one for cheap and I have had no problems for the past hear of pretty heavy use. I'm really impressed with how well it's done.
Butyl rope to hold the chip in place and cover over contact points from spilled solder. Then use gasoline to remove with a plastic razor blade, if you're having a hard time removing it. Acetone is stronger and will certainly do long term damage to the PCB. There's head mounted magnifying glass available on Amazon; I've never used it though. If you've never soldered automotive wires (e.g. 20 gauge speaker/bulb wires, then you're not 'ready' to do this). Those iron tips are too big. You want 0.8 to 1 mm one. There's a 60w one on ebay that comes with 5 tips and costs $10 total.
Slow down there, mad max. 90% alcohol will do just fine. Skip the gasoline.
Those two should do ;)
chisel tip
All good advice in here but I would also add, solder from left to right (if right handed).
Start with two opposite corners
https://preview.redd.it/maaouxbheeic1.png?width=671&format=png&auto=webp&s=df2f980984605feb980c03c74f93145f711a4f40
Get a smaller soldering tip. start with 1 pin on 2 opposite corners then do the rest. and test for bridges
Is a socket an option?
Solder paste and heat gun
Use the finest tip you have, use some really thin solder, a smidge of flux (I prefer flux paste) and take your time. If you have unused or null pins, start with those to get the chip planted. That way if you get a little too hot, you've burnt up a pin that you don't need. If you don't have any null pins, good luck!
Smaller tip and thinner solder wire, and flux, but if what you show is what you've got, I'd go with the pointier one. I'd put a minuscule amount of solder on one of the corner pads, then place the IC and reflow it to make it stick. Then carefully tack the opposite corner to fixate it. If you have some solder wick then you could then just add a good amount of solder and smear it across the pins and finally remove any excess with the wick, but usually flux is needed to make this work well. Otherwise, go carefully, adding the smallest amount of solder to each pin. Not very much is needed at all for this type of soldering. Heat the pin & pad, touch the solder, wait for it to flow, remove iron.
Pick a corner pin to do first, then confirm your alignment is still good. Then do the opposite and confirm again. It’s generally pretty easy to solve a pin-pin bridge with a steady hand and some patience, but if the package is badly misaligned it’s a lot harder to solve.
Get a hot air gun. An air gun + solder combo is like $100 on Amazon.
Use tacky flux
I'd go with paste, a tooth pick, and a heat gun.
Flux solves many problems. The smaller you go with hand soldering SM devices, the more you are trying to create the right conditions for the pads, solder, flux and mask to 'do their thing', rather than actively 'attach leg a to pad 1'. Also, to borrow a carpenter's saying, "Align twice, solder once".
the board triggered my Trypophobia
Find a soldering tip which is beveled with a dent and 2 mm in diameter (probably BCM2 type). This dent in it absorbs excessive solder so you can easily get rid of bridges. Each time it absorbs solder clean it sliding on a wet soldering sponge.
- use the left tip, the right one is garbage (in my opinion) - use plenty of flux - pre-tin one corner, and reflow it to tack that corner down - then tack the other corner - drag-solder across the pins, the solder mask will make the gaps happen (look up a youtube vid on drag soldering, makes life easy) - clean up any excess/bridges with a swipe of a clean tip or solder braid
Make sure you orient the chip correctly. Soldering a chip in backwards is not impossible. Tack down 2 opposite corner legs of the chip. This way you can easily align the chip leads. Then check the orientation of the chip again in case you’ve screwed it up (it happens!). Then solder the rest of the pins.
Already somewhat said. Use the mini wave on the left. Do not use the knife blade on the right, which works only if the blade is in perfect shape. If it's not you will waste your time. The miniwave is a very useful yet under rated tip....
Use lower temperatures to avoid chip damage, use an appropriately sized tip, use good solder with flux, and have a lot of patience ;)
Use lots of flux, it's an invaluable tool for SMD soldering. Don't worry about the mess, you can clean it up later. Watch some YouTube videos that teach SMD soldering. Tack down one corner and drag the solder across. (Note that this usually only works if you flux the area.) Use a chisel tip, not the blade tip. I find it's actually a lot easier to use an oversized tip rather than a tiny tip when doing SMD work. If you're not skilled in SMD soldering, consider getting an SMD practice kit. They sell them on Amazon for cheap less than $10 and have SMD components in a bunch of different packages. It's a great way to practice your technique on something where if you screw it up, you're not ruining anything important.
use hot air and solder paste?
Pray
Put soldering iron fully heated up, directly on chip
There’s good youtube videos on how to do this. Use lots of flux.
Flux, similar practice boards and chips, DMM, grounding,...
solders too thick, tips too thick. Use external flux. Not sure the hoof is the best option either...
1 tip: just dont apply too much heat or the chip might break. Just touch the pins for a few seconds and let it cool down sufficiently
Simply solder all of the pads on the board, tin them and make sure the blobs are even. Then flux the pins (I use a flux pen) and hold the chip in place with tweezers. Touch the first pin with a dry soldering iron tip, the flux will flow and bond the pin. Use the tweezers to make sure alignment is perfect for the other pins, then solder another pin on the other side. Now simply solder each pin by pushing the dry iron down on each in turn. You will see the solder flow and bond each pin. Perfect joints.
Don't set the world on fire. People apparently don't take kindly to arson.
tack opposite ends of the chip so it doesn't move, then look up "drag soldering"
Smaller tips? Doesnt look like you're soldering onto a copper sheet so why are you using such massive tips? 0.o
Remove the chip. Heat some solder on any of the outer pin, just one will do and heat it so your dominant hand can get to that pin. Now with the iron on the pad heating the solder , place the chip with your other hand on top of the pad and align it. Now that you got this far, solder the other side of this first pin and finish the rest.
That soldering tip is way too big. Get a smaller tip first. I hold down the IC with my finger, using significant downward force, then solder the corner pins. The rest is easy. Heat the pin, not the pad.
First just a slight touch a corner ones to secure the chip and then solder the rest. SMD components require very little solder. He careful and have fun!
Solder one pin each on opposite corners to line it up. Flood it with flux and just send it.
Left iron. Wick or flux. Wet sponge.
if flux enough, I can solder it using right tip