Surface Mount Components - Page 1
Forum section: electronics / projects

author: Harb
author_rank: Regular Contributor
timestamp: May 30, 2017, 10:46:24 am
content: I mainly put things together by hand, under the microscope.I find myself using mostly 0402 , 0603 , 0805 and the odd 1206 components......... what do you guys mainly use.........just wondering really

author: tautech
author_rank: Super Contributor
timestamp: May 30, 2017, 11:05:36 am
content: 0805 because even with old eyes I only need a magnifying headset.

author: Harb
author_rank: Regular Contributor
timestamp: May 30, 2017, 11:13:24 am
content: Yeah, I am only 54 and I am amazed at how my eyes have gone down hill in low light........I am sure the cops think I am growing weed in my lab lol........I think it can be seen from space on a cloudy night

author: GreyWoolfe
author_rank: Unknown
timestamp: May 30, 2017, 11:52:49 am
content: Quote from: Harb on May 30, 2017, 11:13:24 amRight there with you on the lighting. I have an 8 foot workbench with 2 4 foot, 6 bulb LED light fixtures that put out 12,000 Lumens each. Definitely daylight on my workbench. My bench is an evening waypoint for the local commuter airport that's about a 1/2 mile away.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 30, 2017, 12:49:01 pm
content: Quote from: tautech on May 30, 2017, 11:05:36 amI like 0603. So much cheaper than 0805.

author: schmitt trigger
author_rank: Super Contributor
timestamp: May 30, 2017, 01:17:31 pm
content: I'm 61 years old, and for that reason I exclusively use 0805 and SOICs.I've made projects employing 0603 and even the occasional 0402, but they are so difficult (for me at least) that I don't enjoy building them.What other posters have mentioned is correct: You need plenty of light and a good magnifying glass. If you can afford it, an USB microscope will allow to find any soldering errors later.

author: fourtytwo42
author_rank: Super Contributor
timestamp: May 30, 2017, 01:26:22 pm
content: I try very hard not to use SMT at all BUT it's getting more and more difficult to get through hole parts as many chips are only produced in SMT so I kinda design them out! Two reasons, one is simple tools and even simpler eyesight but the other is the necessity for pcb's, these make a project very expensive so I only use them when forced. Two recent examples an audio processor where the DSP was only in SMT and there I used 0603 minimum for de-couplers and an SMPS where a pcb was essential for the high voltage but the control logic is in through-hole on stripboard as a plug in module.

author: robotix3
author_rank: Regular Contributor
timestamp: May 30, 2017, 03:55:59 pm
content: I only go bigger than 0402 when I have to. I've never needed to use magnification. I've soldered a few 1mmx1mm ICs, not fun.EDIT: I have to look at a board under a microscope sometimes if I have a bad joint, of course.

author: m98
author_rank: Frequent Contributor
timestamp: May 30, 2017, 04:05:37 pm
content: I use 0805 passives for my self-etched boards because then I can still easily fit at least one trace between the pads. They're also much easier to solder with a soldering iron than the smaller sizes. For professionally manufactured boards I mostly use 0402.

author: KL27x
author_rank: Super Contributor
timestamp: May 30, 2017, 07:14:25 pm
content: 0603, because1. I'm cheap2. it is smallest that is still easy for me to handle with pickup tool.3. the savings cost of 0402 is offset by the number I will lose... that end up in my soldering iron brass wool... and wherever missing socks go. And the power rating is much lower. And the reel size is often twice as large, so the cost savings are really just not there unless for volume machine production purposes.4. 0603 is large enough gap between leads, I can build power resistor or custom resistance by stacking them ad infinitum.They're all easy to solder, if you can see them. The problem with the smaller ones is the handling.... getting them on the board to begin with, and the sticking on the side of the tweezers, playing hide and seek.QuoteI have done this... can do with 0603, but I will use 0805 pads. On toner transfer board with no mask, I will lift the resistor off the board with an air gap, just to be sure.I have supply of 1206 and 0805 zero ohm resistors for larger jumpers, though.

author: ehughes
author_rank: Frequent Contributor
timestamp: May 30, 2017, 07:34:41 pm
content: Coming from someone who has had to make things in volume....Always use the *biggest* you can get away with. There is no reason to use super small unless there is actual packing need or there is an electrical requirement (say RF)Your yields will always be better.

author: DaJMasta
author_rank: Super Contributor
timestamp: May 30, 2017, 07:42:46 pm
content: 0603 seem to be about the right size for me. I can do the soldering by hand without having to get a special grip on the tweezers or something (easy to stay away from the solder pads), and while I do inspect with a loupe, you can see the fillets well enough. It's also about the smallest you can get before a nearby sneeze or shake of the board doesn't send everything flying. Then they're still pretty cheap, have a little extra power dissipation tolerance so you don't have to think too much about packaging in the design, and they're small enough to fit around most devices without blocking too many pins or traces. They're also pretty easy to use in bodging things, and they bridge regular SOIC leads quite easilyIt's also the case that a lot of decoupling caps or filter caps are also 0603, and it simplifies things a bit when you're basically using one main footprint for your passives except where you need bulk capacitance or extra power dissipation or whatnot.

author: Zero999
author_rank: Super Contributor
timestamp: May 30, 2017, 07:57:34 pm
content: One thing to bear in mind, when using small package sizes for capacitors, is you're less likely to getting a good dielectric with a high voltage rating. Small package capacitors are more likely to have a crappy dielectric which reduces the capacitance, as the bias voltage is increased. For decoupling capacitors, go for one in a relatively large package, 100nF, 805 or bigger, for bulk energy storage and another in a small package, 1nF, 603 or smaller, which will have better high frequency response, than the big capacitor.