SOT-363. Are they too small for hobby use? - Page 1
Forum section: electronics / beginners

author: wilfred
author_rank: Super Contributor
timestamp: February 22, 2014, 08:51:26 am
content: /.

author: bingo600
author_rank: Super Contributor
timestamp: February 22, 2014, 09:02:51 am
content: I also have a reel of Dual npn's in that size.Have never used any ....The size is scary for handsoldering even with a pcb./ Bingo

author: amyk
author_rank: Super Contributor
timestamp: February 22, 2014, 09:03:23 am
content: It depends on the individual.Some people can hand-solder 01005, others would be put off by an 0805.

author: AndyC_772
author_rank: Super Contributor
timestamp: February 22, 2014, 09:11:32 am
content: 0.65mm pitch? Achievable at a pinch, but why make life difficult for yourself? If you can get an equivalent transistor for pennies in a SOT23 package, why waste time on a device so tiny?

author: Monkeh
author_rank: Super Contributor
timestamp: February 22, 2014, 09:15:57 am
content: That's not terribly hard to do so long as you've got room around them.With hot air, it's a piece of cake.

author: Unknown
author_rank: Unknown
timestamp: February 22, 2014, 09:30:45 am
content: I just hand-soldered a couple myself the other day on a home-made board photoetched from a laser-printed mask on tracing paper; mostly 0.016" and 0.012" with a couple of 0.010" guard tracks (which were borderline). Yes they're bloody tiny, but not too bad if you lead in by soldering a TSOT-23 or two firstWouldn't want to do a board full of them though. My practical comfortable limit for passives is 0805's, but I can usually manage a few 0603's and the odd 0402.I don't think I've ever seen a 01005

author: tszaboo
author_rank: Super Contributor
timestamp: February 22, 2014, 10:08:07 am
content: I've soldered 0.2mm pitch leadless packages multiple times. Soldering is just the combination of the tool, the light, the magnification, the footprint design and most importantly the person holding the tool. Which part is not obtainable by a hobbyist?

author: lewis
author_rank: Frequent Contributor
timestamp: February 22, 2014, 10:24:18 am
content: Hand soldering SOT-363 is not a problem at all. I usually tin the pads with solder rather than solder paste, use about 300 gallons of flux, wait for it to dry, then place the part in location with some good quality tweezers. The tackiness of the flux is enough to stick it down. I use a decent hot air pencil to reflow, and Mantis Elite to check afterwards. If there's room on the board I use oversize pads to increase peel strength and prevent pad-lift during soldering.I make prototype PCBs in the workshop using the Mega Electronics PA310 tri-tank (bubble etch) and UV exposure unit I've had since I was about 16. It's taken me several years, but I can just about get 4 thou track and space. 8 thou is a piece of cake.

author: peter.mitchell
author_rank: Super Contributor
timestamp: February 22, 2014, 10:50:54 am
content: SOT-363 are fine, the technique i use is as follows;Have a footprint with slightly longer pads on one side.Tin one side of the footprint, and wick away most of the excess, clean used flux ect (step not needed for, HASL boards)Place the part, liberally apply flux.Tin the end of a small conical tip, then coming in from a near vertical angle, just tap the extended part of the pads with the tip - this should tack the part down.Add some more flux, and fresh solder to tip, drag solder the connections starting with the opposite side.Clean.Voilà.This way works pretty well if your shaky, because you don't touch the actual component until its tacked down, and you don't touch it when tacking it either.

author: CM800
author_rank: Frequent Contributor
timestamp: February 22, 2014, 10:55:03 am
content: Have a look at this guy, his soldering is amazing! he does tiny circuits built into components to make 'magic' like this:https://plus.google.com/+HenrykGasperowicz/posts

author: notsob
author_rank: Frequent Contributor
timestamp: February 22, 2014, 11:30:47 am
content: You can 'pin' the sot to the PCB with a tool made from coat hanger wire and solder it down easily, cannot remember who, but someone on this blog had a picture of a home made one that could be held down with a weight.

author: peter.mitchell
author_rank: Super Contributor
timestamp: February 22, 2014, 11:37:31 am
content: Either-or. Works on home made too. TBH it works better on home made because you don't need to worry about making the footprint bigger, you can just use the trace leading up to transfer the heat to "tack" the part. The surface tension, heat and flux will pull the excess solder off the pins.On real cheap chinese production boards there isn't much difference, on parts with a pitch of 0.6mm~ or less the soldermask between pads is fairly hit and miss, so you lose the advantages of being able to heat the pad without touching the component and smooth, flat pads but get the advantage of patchy soldermask between pads? Wooo....

author: free_electron
author_rank: Super Contributor
timestamp: February 22, 2014, 12:16:06 pm
content: No problemo.Things don't get iffy until you hit 0201.. 01005 is undoable. That is just flecks of dust.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 22, 2014, 05:59:03 pm
content: 0.65mm pitch, no problem. I've hand soldered TSSOP packages deadbug style, with flying leads connecting the pins. Tricky, but you just need a steady hand and some skill at soldering (if you're a beginner, maybe you should shelve them for a few years while practicing..?).Cutting traces on copper clad isn't terrifically hard: you only need to make one narrow trace, then an outline of cuts around the area (to form the four corner pads and cut the center trace loose) and one cut down the center (to split three pads into six). A sharp utility blade is the best way to go.If you're in the habit of getting PCBs fabbed (or making them yourself, if you can get the consistency and detail), no problem at all. Easiest way to install fine pitch: tack it down, flood with solder (relatively speaking), then wick out the excess. Just enough stays on the pads.If you wanted them for just 2N3904 sorts of purposes, that sounds like a lot more work than you need for just playing around (let alone breadboarding!). If they are RF transistors, working with RF is kind of a pain anyway, so it'd still be a good bargain.Tim

author: rfbroadband
author_rank: Unknown
timestamp: March 07, 2014, 04:07:29 am
content: SOT 363, is not that bad. You may have to practice a bit. I personally solder down to 0402 by hand and 0.5mm pitch is not a problem. Smaller than 0402 becomes more painful, but beyond 0201 ..no.

author: poorchava
author_rank: Super Contributor
timestamp: March 07, 2014, 01:01:00 pm
content: everything down to 0.5mm and 0603 is a piece of cake. 0402 is annoying but doable. Soldering 0.4mm pitch, 0201 and below passives is a bitch and should be avoided unless there is no other option.

author: tsmith35
author_rank: Frequent Contributor
timestamp: March 07, 2014, 01:37:03 pm
content: Wow, those suckers are tiny...

author: ktemkin
author_rank: Contributor
timestamp: March 07, 2014, 05:25:59 pm
content: Those are definitely hand-solderable; and they shouldn't be that difficult, assuming you have somewhat decent soldering equipment.I have a fairly significant number of students who have soldered components smaller than this pin pitch within a few weeks of their first time soldering. Sure, they've destroyed a few boards and parts along their way to being proficient-- but that's part of the learning process. The real trick is not to get frustrated and give up if you botch the first few solder jobs-- and flux works wonders, of course.

author: tsmith35
author_rank: Frequent Contributor
timestamp: March 07, 2014, 05:40:45 pm
content: Quote from: ktemkin on March 07, 2014, 05:25:59 pmI like to pull old motherboards and other such boards from the trash, then use them as practice boards. Lots of desolder & rework opportunities there.