EEVblog® Electronics Community Forum
EEVblog => EEVblog Specific => Topic started by: bmwm3edward on October 19, 2009, 10:20:07 pm
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First: Hat's off to David. You're out of control, and I agree with everything you've said thus far.
I'm really getting into this EE stuff.
But I am having a little bit of a challenge with these high density chip packaging (SOIC, SSOP, etc).
I'd love to see some tutorials, even a video blog on how to get your SOIC chip onto a breadboard. Soldering tips for this, or whatever. Do I need special flux/solder? Breakout boards? I've seen some breakout boards that look better than others (eg, have solder in channels, already, etc). Special temperature settings, considerations?
Best regards,
Edward
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Did you google for SMD/SMT soldering tutorials?
This site has pretty good one and they have videos.
http://curiousinventor.com/guides/Surface_Mount_Soldering
http://curiousinventor.com/guides/Surface_Mount_Soldering/101
This guy also has very nice videos. Drag soldering is cool.
https://www.youtube.com/user/jkgamm041
Additional flux when soldering SMT components is almost necessary.
SOIC to DIP adapters are available pretty much everywhere. You will also need male goldpins. It all comes to how much you want to pay. But I never had bad adapters, even cheapest I could find from china.
If you don't have soldering station you really dont have to get anything expensive. But you can't save on tips.
I have AOYUE 908 rework with hot air, but you can get 936 which is basically the same without hot air. The secret is that they are copies of old Hakko models. If you get Hakko tips (not "for hakko" but genuine "hakko", with logo on plastic wrap, each tip is wrapped individually) you'll have very good equipment at the lowest possible price. AOYUE tips coming with stations are useless.
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Great articles & videos. Very helpful. Thank you.
I have a XYTRONIC AUTO-TEMP 379, but not sure if my tips are right for the small stuff (first try will be a SOIC, which isn't nearly as tight as those extreme density SMCs). My soldering station works great, but if I'll have to see if my tips are adequate. I'll have to go get a loupe and some flux and see how it goes!!
With my past experience with heat I just cringe watching those guys drag their iron SLOWLY across those pins, but ... they must be designed for that!
Thank you for the info... I'm sure this will be helpful to others too.
Cheers,
Edward
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With my past experience with heat I just cringe watching those guys drag their iron SLOWLY across those pins, but ... they must be designed for that!
Drag soldering? That is done with standard stuff. It is simple. A temperature controlled normal soldering station, and a chisel soldering tip do. A hoof tip would be slightly better, but is really not essential. I wouldn't be surprised to see drag soldering with an unregulated $5 AC soldering iron, but I never did it with one of these.
What you do when drag soldering is that you essentially role a ball of melted solder over the pins with the help of the soldering iron. A little bit of the solder keeps sticking at the pins and pads, and also melts the existing tin on the pins and pads (if they are pre-tinned). That little (really not much) what "sticks" and solidifies makes the solder joint. The key is not the iron or the tip, but flux, flux and flux.
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as said drag soder with a chisel tip, takes a little bit of practice, good solder flux and an iron that'll give a consistent temperature and its not that bad at all, bit of copper braid to rmove bridges.
check out http://www.schmartboard.com/ too.
i saw a neat one yesterday that took some verobard in which that tracks were cut in half lengthways for a soic-8
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An easy method for soldering SMD chips is to totally slather all the pins and pads in solder (so that they are totally shortcircuited as a big glob of solder) and then just use solderwick, it sucks all the excess solder away and leaves solder between the pads and the pins, works really well and is FAST.
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Good info. I'll be giving this my first go shortly. My 30x stereo microscope is coming soon (probably overkill, but for $120, seems like a good idea, per the video someone mentioned above!).
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Got a link for the microscope? sounds pretty cheap!
x30 might be a bit much for general soldering, i used to use x10 at an old job for SMD's
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Request to group-- please provide product-specific recommendations for a stereo-boom microscope... Ideally something that's 'serious' hobby-grade but not that $10,000 Nikon with scanning-tunneling capability. What would you actually get for $120? I'm using a 3x Jeweler's loop now, but the Col. Klink-look just doesn't work for me.
TIA!
-Trent
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Here's how I found the one I ordered:
http://shop.ebay.com/i.html?_trkparms=65%253A12%257C66%253A2%257C39%253A1%257C72%253A2533&_nkw=stereo+microscope+30x&_sticky=1&_trksid=p3286.c0.m14&_sop=15&_sc=1
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same old story :) cheap ebay old used one can be better than a new one. I definitely regret getting the non boom type, but you can change the mount, they're somewhat standard between some models.
http://www.absoluteclarity.com/buy&avoid.htm
this list used to have an avoid, but it seems to have gone, so i guess its just everything else
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Here's how I found the one I ordered:
http://shop.ebay.com/i.html?_trkparms=65%253A12%257C66%253A2%257C39%253A1%257C72%253A2533&_nkw=stereo+microscope+30x&_sticky=1&_trksid=p3286.c0.m14&_sop=15&_sc=1
I'm actually getting a page full of items from this link.
BmwM3Edward, I would sincerely appreciate it if you could do a mini write-up, once you spent some time with your new scope. Its more about the [dead] space [a crappy Mscope would occupy] than the money for me, but don't get me wrong-- the money part is still very important!
Thanks,
-Trent
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The microscope arrived today and I've given it a quick test drive. I bought one like this:
http://cgi.ebay.com/NEW-BINOCULAR-STEREO-MICROSCOPE-20X-30X-40X-60X_W0QQitemZ400082000032QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5d26bed8a0 (http://cgi.ebay.com/NEW-BINOCULAR-STEREO-MICROSCOPE-20X-30X-40X-60X_W0QQitemZ400082000032QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5d26bed8a0)
If you don't want to read my entire post, my first impressions of this microscope are very good and I recommend it. Great bang for buck.
The difference between the 30x and th 60x is the extra objective lenses that it comes with. The scope came with two sets: a 10x and a 15x set. Then, there's the primary lens that sits just above the object you're viewing - which can rotate allowing two modes - 2x and 4x. This gives you combinations of 20x,30x,40x and 60x. The big difference between the high magnification modes and lower modes is light gathering and depth of field. The higher the magnification, the less the depth of field and the less light.
This scope has a light that is quite bright (and hot if you accidentally touch it) that gives plenty of warm white light. This scope also has a 2nd light that illuminate the box from underneath for viewing transluscent things/slides, etc. The amount of light loss and depth of field loss does not present a problem, but is noticable.
The first thing I inspected was my iPhone. I was astonished that I could actually peer into the scratches (the 3D effect is amazing - something you don't get in a monoscoping loupe). It's like looking down at your feet and seeing a small ditch. And when you move the focus from the screen, you can "drop down" through the screen surface into the LCD elements on the screen (the screen surface becomes out of focus when the screen's matrix comes into focus). I could see very clear color rectangles that resembled an old Sony triniton tube up close. That kind of 3D depth of field is amazing. The next thing I did was pull a couple hairs out of my head and take a peek. Was akin to looking at a pencit at 12" away from your face, you could actually see the texture of the hair and its sheen.
Very sharp, good feel, good light. Good bargain. Fast shipping. No frills.
What I would expect in more expensive models would be an even focus field across the viewfinder. That is, when the center is in focus, the outsides sometimes aren't, but since you're always tooling with the focus, it's just something you adjust as you look around. For this money, a minor moan.