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.
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Baking a Raspberry Pi Pico W before reflow soldering?
JLCPCB is trying to tell me that the RPi Pico W needs to be baked to reduce moisture before putting it through reflow soldering. They're saying that "It is moisture-sensitive according to the ...
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Solder bridges on 0.5mm pitch connector after reflow
I am trying to solder this 100 pads SMD connector (LSHM-150-04.0-L-DV-A-S-K-TR), and no matter what I do, the pins are always bridging here and there. First, I tried to solder it normally with paste ...
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W5500 Chip Intermittent Act/CRS light on custom PCB
I have built a custom Arduino-like board with the W5500 and atmega328pb. I am reaching out to see if anyone has had a similar experience when working with the W5500 chip:
The current board I am ...
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X-Ray inspection criteria
We are seeing board problems when testing a new batch of boards at high temperatures (70°C). This is using leaded solder (and OEM leaded BGA balls) and the component is rated to 100°C.
We believe one ...
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What is the best solution to keeping heavier components on a double-sided PCB while going through second pass reflow?
I am trying to do some research as I have many customers who face this issue with their parts falling off the board during the second pass. What has worked for you? Many applications are different ...
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Is there flux that doesn't brown under heat?
Adding flux (MG8341) to rework a component is resulting in ugly brown stains as shown in the picture below; this is a flexible circuit board with white cover-lay. The flux started to turn brown add ...
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Soldering with SAC on a glass PCB
I’m having trouble getting the solder paste to wet my glass PCBs.
I am using SAC305 solder.
Funny that it works fine on FR-4 but with glass it just balls up.
Maybe it is because glass conducts heat ...
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Cheap vs. expensive reflow oven
I am trying to build my capacity to solder SMD onto two-sided boards. As far as I understand, for example from this post, a reflow oven is better than a hotplate for reasons of uniformity in ...
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Reflow oven control technique
I am developing a DIY reflow oven using a 10L common electric oven with quartz heating elements.
Below is a graph that represents the oven's step response (open loop response):
In blue: oven's step ...
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Should I throw these boards with soldering issues out?
I've just baked some boards. The first two looked normal, but upon closer inspection I noticed that paste did not melt under one chip with exposed pad package. I used a slightly different profile with ...
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PCB warping during Reflow
I have design a PCB size about 100x60mm it reflow very nice on the hot plate but If I convert my PCB to a panelization 2x3 quantities size became 200x180, the edges began to lift up due to expansion ...
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Reflow soldering with decreased footprint size fully within pad
So the original footprint is first, followed is the edited footprint to allow for inner pads to be accessed.
As you will notice the extended pad footprint is smaller than the pad. Will this cause ...
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Solder SMT/SMD with a rework preheater?
Is it possible to solder SMT/SMD chips using a rework preheater (e.g. a Model 5040-XR3)? What "gotchas" go with this method of SMT/SMD soldering?
I know it's best to use a real reflow oven, ...
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Disobeying recommended pad size of 0603 LED
I need to pack a cluster of 0603 LEDs (https://docs.rs-online.com/c349/0900766b81180479.pdf) as close together as possible on a PCB. The datasheet recommends a pad-to-pad width of 2.3mm.
As the board ...
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What glue to use for edge bonds on a laptop NB
I'm trying to reball the northbrige of my HP Pavilion DV4-1212LA because it stopped working from one day to the other. I've checked, and all of the voltages are present. The laptop itself posts the ...
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