Questions tagged [reflow]

Reflow soldering is a type of soldering where solder paste is applied to the pads, after which the components are placed on top and then it is baked in an oven.

Filter by
Sorted by
Tagged with
2
votes
2answers
44 views

Going over IC max temp in reflow oven?

I'm a beginner-ish in PCB making and I want my workflow to be faster by using an oven instead of doing all the solder by hand. I searched for few hours without answer to my question. A low temperature ...
0
votes
0answers
9 views

Pick Up Area / Centroid for surface mount connector

I'm about to use an SMD connector on a PCB that will be machine assembled. It is a right angle connector (datasheet). I can't find where the centroid should be for its package. (I have previously ...
1
vote
0answers
104 views

Repairing an SSD using a soldering iron vs oven reflow?

I'm trying to recover data from a cheap kingspec ssd that stopped working some months ago. It is not recognized by the computer at all. I get some messages saying the computer is trying to connect to ...
2
votes
1answer
99 views

BGA VCC and VSS shorted after desoldering

I am really confused with working with BGA chips. I am new to this but have been following other guides so I thought I should give it a try. I am using a DIY pre heater that has a 800watt IR bottom ...
0
votes
1answer
37 views

Do I need to Reduce the Width of a Power Trace for Thermal Relief When it's Passing Through a Pin on the Chip?

I'm routing a PCB. Currently, all power traces are 20 mils. A QFP chip on the board requires multiple voltage rails to operate, I found the easiest solution is passing a power trace through a pin on ...
1
vote
0answers
27 views

Practical Issues with Surface Mount Heatsinks?

I'm considering using surface mount heat sinks for D2PAK devices on a PCB. These heat sinks are bent sheet metal frames with tin/lead plating in tape/reel packaging which are suitable for soldering ...
0
votes
2answers
77 views

Desoldering SMT components with a reflow oven

I'm wondering if it's possible to desolder all smd components on a PCB using a reflow oven? My plan is to hang the PCB upside down over a piece of aluminum foil, use a standard reflow profile and let ...
0
votes
1answer
62 views

SMD reflow oven baseplate material

I’m (for fun and hobby projects) making a DIY reflow oven (box, not conveyor) based on resisting heating elements and convection. I initially used a base to hold PCB made of steel wire, but that ...
1
vote
1answer
65 views

Should I apply soldermask over SMT thermal pads?

On page 8 and 9 of the following datasheet, there's a description of thermal pads for this MOSFET: https://www.vishay.com/docs/63302/si2342ds.pdf What I am wondering is: I will design the footprint ...
4
votes
1answer
106 views

How to solder large smd components on a PCB with 2oz copper

I’ve got a large inductor that needs to be soldered to my board. The pads are hidden underneath the component so hand soldering is not an option. The data sheet says to reflow at 260c for 40 seconds ...
0
votes
2answers
483 views

Reflow Soldering at home

I’m trying to solder my TSSOP-16 chip to the DIP adapter. I’m planning to apply solder paste to the adapter’s pads, put the chip on the adapter and then use my kitchen oven to melt solder paste and ...
9
votes
8answers
2k views

Assembly of PCBs containing a mix of SMT and thru-hole parts?

I have a batch of beta PCBs which we have to assemble in our lab. We have an APS manual pick-and-place machine and a tabletop reflow oven so I thought assembly tomorrow would be easy and straight ...
0
votes
2answers
232 views

Solder bridging when reflowing QFP

Today I attempted to reflow solder a board using a solder paste mask and a hot air station but for a QFP chip, I got a of solder bridging. This has generally been my experience with trying to solder ...
4
votes
1answer
94 views

Small DFN chips come out twisted from the oven

This is a 2 x 2 mm chip with 12 no lead contact points. Half of the time I get it out of the reflow oven, it's twisted like in the image below. I am using a stencil in order to lay the paste down and ...
2
votes
1answer
82 views

Can a castellated PCB/module have electrolytic capacitors in it?

We're designing a small module (3in x 3in) that will have castellations on the edges for connection. I just watched a video on castellation PCB design. The video talked about the module going thru ...
0
votes
1answer
121 views

Causes of burning solder paste

I’ve recently acquired a modified T962A reflow oven and have been experimenting with profiles. I’ve had to really ramp up the peak temperature and time at peak temperature to even have any chance at ...
1
vote
2answers
85 views

Reflow soldering, pin longer than pad?

I was designing the footprint for this FPC connector: Datasheet The recommended land pattern is shown here: The issue I encountered is that the pins on one side protrude outside of the pad: I ...
4
votes
1answer
129 views

When I rework an SMD capacitor or resistor, it will sometimes stick to the soldering tip. Does this high temp then destroy it?

When I rework 0402 capacitors, then often stick to the tip of the soldering iron. My iron is set at 350. I then discard the cap because I am worried the sustained temp for a few seconds has destroyed ...
5
votes
1answer
875 views

Do SMD resistors have to be reflowed black side up, or is black side down okay?

I reflow my own boards in a toaster oven. When I drop my resistors off the paper tape, I always flip them over to black side up before I place them. Should I bother if it doesn't really matter?
1
vote
2answers
540 views

Burned PCB with reflow soldering

I made a homemade reflow oven and used it for the first time to solder a board. As you can see in the image below, I botched the job and burned the solder connections (not surprisingly, the board does ...
0
votes
2answers
80 views

reflow oven issues with RO4003 PCB

Im trying to reflow some RF pcbs in a legit reflow oven. The PCBs material is "Rogers RO4003 305 Um" and 3 layer. (Its a very thin pcb) If temperature is high enough to reflow the paste, the pcb ...
0
votes
3answers
132 views

Makeshift SMT Station. Any suggestions? [closed]

I am trying to do some surface mount soldering for my project and have hit a few snags. My hot air gun works perfectly fine for most of the PCBs I am making but one type in particular is problematic....
0
votes
1answer
81 views

How to prevent a low duty cycle load from flickering lights

This is a follow up question to this: Alternatives to Large Transformer or PSU for Driving DC Heater I've hooked up 120v AC to a zero crossing SSR and a 3.2 ohm resistive load. To get my desired ...
0
votes
2answers
58 views

Alternatives to Large Transformer or PSU for Driving DC Heater

I have a 3D printer heated bed, instead of 3d printing I want to use it for reflow soldering. The bed is intended to operate at 70c, using 12v or 24v. It can be wired in series or parallel depending ...
1
vote
1answer
140 views

Transitioning to lead-free reflow and soldering

I have recently been thinking about moving to a lead-free process for my production and though I've been reading up, I was hoping someone more knowledgable than me would be able to point me in the ...
6
votes
1answer
548 views

Rule of thumb for surface tension when placing components on the secondary side of a board

I've been working on my first multi-layer PCB design, and have been placing a variety of components on the secondary side of the board (mostly decoupling capacitors and QFN ICs). However, some of ...
3
votes
3answers
184 views

SMD solder failure due to probing? How to solve it?

I was visually inspecting a board that had functional problems, and I have noticed a strange pattern in the pads surrounding the IC. Upon electrical inspection, there are two pads that are shorted ...
3
votes
1answer
133 views

LEDs lighting up while being baked inside a reflow oven

This is a board with 80 3535 LEDs on it just after completing the reflow cycle in my home-made reflow oven. Why are the bottom corner LEDs lit up? Rather, how is this happening?
0
votes
1answer
136 views

exploding cartridge heater

I bought this cartridge heater for my reflow oven. Since this was rated for 220VAC I connected it to my mains through an SSR which is in turn controlled by the reflow oven firmware. The firmware goes ...
2
votes
1answer
1k views

Should I spray some flux on my board before putting it in the reflow oven?

I am using Tin-Lead solderpaste to make my prototype circuits. This is the exact solder paste: ALPHA OM-5100 (https://alphaassembly.com/Products/Solder-Paste/OM-5100)     ...
10
votes
1answer
587 views

Can you program a surface mount IC with flash memory and then reflow solder them?

I know that many chips, such as the ATMEGA328P-AU list flash storage lifetimes at certain temperatures, but they usually cap out at 100° C. I know that, ideally, one should include leads on their ...
2
votes
2answers
530 views

Baking SMD integrated circuits for prolong time

I recieved samples of AD7175-2 and AD5684R with an instruction: If these samples are to be subjected to solder reflow or high temperature process, they must be baked for 24 hours at 125°C prior ...
1
vote
0answers
448 views

FR-4 discoloring in reflow oven

Is it normal for exposed (no solder mask) FR-4 to blacken during reflow? We're using a fairly ordinary profile with a max at 233C, about 5 minutes total and only about 60 seconds above 200C. I ...
4
votes
5answers
8k views

Using a home oven for solder paste

I'm doing a project and I have a PCB which needs surface mount components attaching to it. One component has already been attached, and I have some 138deg solder paste in a syringe. This is possibly ...
1
vote
1answer
146 views

Second Reflow with BGA

For a DIY project BGA reflow soldering is really expensive to get it done by commercial means. I approached a university which allowed me to avail the help of their staff but they said they would only ...
0
votes
2answers
137 views

Probe testing LFCSP components with a multimeter

If I reflow a LFCSP IC such as an ADV7180 I probably won't be able to see any solder bridges or unsoldered pads because the pads are under the chip. Can I safely test for bridges by using a multimeter ...
4
votes
1answer
415 views

How to bake MSL components for DIY reflow?

I'm intending to reflow solder some components from Analog Devices. Since they are an LFCSP package, hand-soldering is not possible. They arrived with a warning that they are moisture sensitive (MSL3) ...
14
votes
3answers
5k views

Is it safe to repeat reflow soldering?

I have a board that is partially reflow soldered with a QFN and a couple of 0603 capacitors and resistors. I wanted to test functionality with this stage before I go ahead and place the other ...
0
votes
1answer
41 views

S-PFQP-G80 package

I am having some troubles soldering a S-PFQP-G80 package since I get solder bridges between pins after putting it into the reflow oven and I was wondering it would make sense to decrease the pad ...
0
votes
1answer
138 views

Solder paste for stencil

I'm going to solder a small pcb with reflow process and I'd like to use a stencil for that because the components are too tiny for hand soldering iron. The pcb has a QFN32 (0.5mm pitch and exposed pad)...
3
votes
1answer
3k views

PCB Reflow in oven, will solder melt before VRM's, caps etc get damaged?

From Wikipedia: Alloys commonly used for electrical soldering are 60/40 Sn-Pb, which melts at 188 °C (370 °F), and 63/37 Sn-Pb used principally in electrical/electronic work. 63/37 is a eutectic ...
1
vote
3answers
3k views

Reflow oven vs even hot plate

I've recently been searching for a simple, easy yet cheap way to reflow SMDs on a PCB board as I have never tried it before and always wanted to create a small and compact circuit. I then found a ...
0
votes
1answer
471 views

Do 0402 chip component need solder mask web between the pads?

In my board, all 0402 parts are using gang solder mask. The pad to pad distance is 10 mils. Is there any risk of solder short? Do I need to suggest applying solder mask web between the pads for all ...
8
votes
2answers
766 views

Why do the Sparkfun and Adafruit Eagle libraries use smaller footprints than the manufacturer's recommended land pattern?

I'm comparing two datasheets from Micron and Infineon to the Sparkfun and Adafruit footprints for TSSOP-28 Both the footprints use an SMD pad size of 1.0x0.3 mm, while the manufacturers recommend ...
-1
votes
1answer
455 views

What's the min space between exposed via pad to exposed component pad during reflow?

In my opinion, the solder will not run into the via as long as there is a reliable soldermask web between them. Is that right? As I know, PCB manufacturers change gerbers all the time to make the ...
2
votes
2answers
2k views

In order to avoid solder bridges during reflow, What is the minimum pad-to-pad spacing?

With regard to DFM, I am wondering if there is no risk of solder bridge during reflow as long as there is a soldermask web between the pads? Soldermask clearance(2 mils*2) + soldermask web(4 mils) = 8 ...
9
votes
3answers
3k views

Solder paste not wetting at all

I have an issue with solder paste, I would like to know its origin so I can fix the problem and solder by components properly. I use a lead free Sn42/Bi57.6/Ag0.4 solder paste, manufactured by ...
1
vote
2answers
142 views

What situation does it make sense to mod a toaster oven instead of just buying a reflow oven?

I have seen kits like this online http://whizoo.com/reflowoven to modify a toaster oven to use as a reflow oven, but they seem like a significant amount more work and lower quality than just buying ...
1
vote
1answer
112 views

Baking 0603 Components

I have a few 0603 LEDs that come with the instruction to bake them if they had the chance to draw moisture. What is the best way to do that? Can I leave them in the tape, so I don't lose the ...
0
votes
0answers
178 views

Vacuum dessication of MSL components?

The standard method of removing moisture from MSL-sensitive SMD components prior to reflow is to bake in an oven for 12 hours or more. Without baking, there is a possibility of popcorning, as the ...