I've recently been soldering ball-grid-array parts to boards. This is relatively new to me, and there has been a few mishaps with my technique. I was just wondering how does the community perform BGA soldering? What techniques/equipment do you use to make this process more efficient and less error prone?  My technique involves using a Hakko FR-830 Preheater to do the work. I use an old board holder to hold my board in place, and then I apply some solder to the board using a syringe (ChipQuik SMD291AX). My part is a 6x6 BGA array, with the pads 1mm apart from each other in a square grid. Once I place the solder onto the pads, I slowly put the part onto the pads, aligned as close as possible. Then, once it's ready, I turn on the preheater through its temperatures from 150-300 degrees Celcius at 50 degree intervals for about a minute and a half at each temperature. The apparatus is not enclosed, so I put a piece of metal over my board holder so that the top of my PCB board is not exposed to open air.   My process is not exactly ideal, but thus far, it works alright. However, I noticed that the solder doesn't seem like it really 'melted'. I think that this might be because of my methods, and running a hot air gun on the sides doesn't really help much. Any tips or suggestions? This is all done in-house, and I have to do this by myself, so learning how to do it better would be helpful.
122175
BGA seems to be somewhat of a showstopper for the diy community, especially with the newer more powerful parts being almost exclusively bga.  I know it can be done with the skillet/toaster oven method, but it seems like there is no way of inspecting for defects without an x-ray machine except   for maybe this method .  So is reflowing using these methods relatively high yielding or is this just not worth doing at home?
120945
I would like to manufacture DIY PCB. I am planning to make a UV box like on , then I wonder how I can determine the best UV exposure time?   or if I use the Sun as the UV source, how I can determine the exposure time as the strength of sun light varies over the time?   What happened if the board exposed the UV light longer than it supposed to?
82060
I'm quite blank when it comes to electronics, but am trying to learn...   So I bought a  from Banggood to get some solder practice.   As you can see from , the leds will change color and turn on and off in different patterns.    question already establish that two pin RGB leds most likely contains some kind of micro chip, but it doesn't say anything about how they can be controlled.  The chip on the board is a STC15F204AE, and I guess that's the one responsible for creating the patterns. But again - how?  Is it just a fixed sequence pattern in the LED, and then the chip ensures that each LED receives power right after the previous, or is the LEDs addressable some how?
69807
I have imported a schematic in PCB and placed components. But one thing is missing, its not showing pads names as they are appearing in schematic. It can only show Designator and Comments of component in PCB but not the pads name.   How can I make them appear ?  Thank you  Added screenshot, how to do like this. Like 1 appearing next to pin 1, 2 appearing next to pin 2. But when I add a header, nothing appears, only the entire component designator appears.
30982
I found the  at Digikey.  The datasheet says the device is rated for 400A @ 25C, 1200A @ 25C for 1ms, with a voltage rating of 300V and PD of 1000W.  Really?  This TO-264 package can control 400A of current all day long?  I can short out my TIG welder with it in DC mode?  How do those leads even carry 400A of current?
92843
Some ICs have their pins labelled only with numerical values and some use alphanumeric labels. I want to know what is the correct naming term for these cases.  Is it ok to call all the chips with alphanumeric labels BGA (ball grid array)?  And for chips with only numeric pin labels the chip should be called DIL (dual in line)?
62156
I'm working on a 4 layer PCB with internal 2 layers being power and GND... 2 outside layers are signal. Is it better to have a pour on the outside layers or just leave them empty except for the signals?
90226
I am creating a custom box that will contain 3 * 400 watt metal halide bulbs (1200 watt total). The box will remain closed for 60 minutes, open for the next 60 minutes, then closed, then open and so on.. for a period of 10 hours. The box will open/close from the the front panel (the "door") using Arduino and Servo motors.   Since the bulbs will be generating a lot of heat I will attach a Duct Fan at 240 CFM on top of the box (is the top the best place to put it?). Something like this:   The box itself will be made out of wood so I will coat it with a heat resistant spray from the inside so it doesn't catch on fire. Something like this:   When the box is open I will need the box to emit as much light as possible. Therefore, I will coat the inside with a reflective substance (something like this: ) so all light rays are dispersed from the box..  What do you think?  Thanks
8155
Hey I want to connect the bottom loop with the top loop so that it forms a solid.  I have tried selecting multiple vertices and pressing F but that just creates a large face which I do not want. I have tried using grid fill bu that doesn't work either. The solution that seems to work is by selecting four vertices and pressing F and then selecting the next 4 and pressing F and on and on. That just takes too long.
72975
I've made a couple of PCBs which need the odd few 10 mil tracks, but are mostly 20/30 mil. Unfortunately the etching process isn't fantastic and there are numerous breaks in the traces, most of them small.  I've managed to convince solder lumps to go over the top of the smaller gaps, and have used components legs to bridge some of the larger ones. The solder lumps don't feel particularly reliable though, and there are some gaps which are too small and awkward to get a piece of wire across but too big to be bridged with just the iron.  Are there any standard ways to reliably fix up broken traces?  Update: Thanks for the suggestions everyone!  I found and tried out a silver conductive pen. As a first time user I found it difficult to dispense, and obviously I didn't use enough of it or mix it properly because it didn't even end up being conductive.  It seems like the main problem was that I was trying to use pieces of wire which are too short. I found some small gauge tinned wire and used longer lengths, running it over significant lengths of good track on either side of the fault. That makes it much easier to position, and you can tack them down one end at a time.
119972
I've been to a couple introductory Altium trainings and everything goes fine and dandy. This is the actual first board I am working on by myself. I've been learning so much just by doing stuff myself but there is something that I can't seem to quite understand.   Whenever I transfer my schematic to the PCB is is placed inside this reddish box, I believe it is a Room. All the examples I saw during training didn't do this. And if I move the components outside the box they turn green (DRC error maybe?)  Does anyone know what this means?
120956
I was reading about tin alloys for electronics soldering and found it it has about 40% of lead in composition. Lead, everyone knows, it's very dangerous to breathe due to being a heavy metal. Also, I found some recommendations using the combination of an exhauster and a respirator when working with soldering. Is there any international regularization of which respirator type should I use? If not, which type do you recommend? Beyond this, is there any additional safety equipment recommended?  For economics reasons and for better soldering resistance, I've already discarded Pb free solder reflow.
83297
For the magnitude of nF or µF capacitors, I hope I can build them on a PCB board. The capacitor is like a two metal layer and something between them.   Is this possible?   Not buying the capacitor, just design the capacitor on the PCB board. Double metal layers on the PCB board.
41654
How do I share a single crystal (not a complete oscillator module) between two micros? Is it OK to just connect everything as normal for the first micro and also directly connect its XO to the XI of the second microcontroller? I expect to place the micros very close together on the board.
77967
I read that this processor is BGA. That would mean that it is soldered to the motherboard? Can an average laptop technician replace it?  This processor is very slow, it scores only 600 on the Passmark CPU Benchmark.
49861
So I've done this so far, and  know one of the components is a 50ohm resistor. However I dont know where to go from here. How do i decide if its an inductor or a capacitor? This is a past paper exam so im aware the other component is a 125nH inductor... but how do i get to that?
64721
Basic question here, but it's driving me insane!  The solder does not seem to stick to the tip of my soldering iron. After the iron heats up, the tip appears black (sometimes on all sides and sometimes on one side), then either it doesn't melt the solder at all, or it I fiddle around with it for a while; it melts the solder, but the solder rolls into itself into a ball and doesn't stick to the tip.  I've seen this many times while soldering before and usually it's solved by cleaning the tip on a soldering sponge or cooling it down and scraping the tip off with a blade, but I have scraped this particular one many times and still it's the same problem: it heats up and gets black, then the solder doesn't stick to it.  It doesn't help that this soldering iron has a very fine tip and I have to use it to solder very tiny chips and wires under a microscope (I'm just starting to learn soldering under microscopes).  Any ideas on what I can do?    PS: Is scraping the tip a bad idea? I have been doing it with my other bigger soldering irons and it seemed to work (at least in most cases) but I am not sure whether it is a good solution or not.