just note: always check your datasheet for thermal profile, some parts need to be preheated for a minute or so at lower than soldering temperature, so that they wont be damaged by thermal stress
this video is perfect., only remember that when your pcb is very cool it's recomended to use a preheater for this optimal results. , I think is a very very good video.
Can I just leave it their without soldering the sides? I mean those are just indicator right? I'm having difficulty soldering specially when pins are higher than 48
HowTo DIY homeMade Electronica do go with a reflow technique first preheat the pcb and then go to required temp for the solder you using. This will surely help prevent the discolouration of your pcb.
if you don't preheat the pcb, there is a big temp gradient loss from the IC to the board and you end up having to apply more heat at higher temperature, which leads to burning the fiber glass pcb. If you preheat you can reach liquid state at lower air pencil temperature because there is much less loss from IC to pcb.
Did I understand right when he said that he put a couple of vias down that he drilled new holes into the board? How can he tell that there are no tracks among the layers?
you can buy the right size square shield little tub with hollow on bottom and 4 tapered walls made by JBC that isolate the QFN from its surrounding, then you do apply the same thermal profile. First ramp, soak, then reflow with hot air pencil. The expensive hot air pencil have a vacuum suction head build inside the pencil head. But if you don't have that, I am guessing, i could be wrong that once you reach eutectic liquidness, you can just shove the IC away, then clean remaining solder with a hot solder removal vacuum tool.
No concerns of thermal shock from direct top heating of the IC to the point that solder melts on the leads? No concerns of cold solder joints from moving the component while cooling? No concerns with inactivated flux corroding the board over time?
The idea is to minimize temperature gradient at every point on the board near the IC in the presoak stage. You want to reach a uniform temperature. This is key.This is very dooable. You can use a thermocouple taped to the pcb with kastan tape to help you get an idea of pcb temperature while using the HAP. You are trying to replicate the reflow profile with only a preheater and a hot air pencil. When you start the reflow ramp, you start with the pencil high above the IC and work it down. If you do the presoak well you will not shock the IC because there will be low temperature gradient between the IC and the PCB which minimizes heat loss and you will reach liquidity at lower HAP temp. But if you skip preheat, there is a ton of loss and you have to crank up the HAP temperature to reflow and then you will shock and damage the part. You are right, about you should not mov the part during cooling but when you are above eutectic temperature the phase is liquid and it's ok to move the ic. If you solder is not eutectic type, it will go in a plastic intermediate phase between liquid and solid where there is risk of forming cold joint if you move the part.
just note: always check your datasheet for thermal profile, some parts need to be preheated for a minute or so at lower than soldering temperature, so that they wont be damaged by thermal stress
just note: always check your datasheet for thermal profile, some parts need to be preheated for a minute or so at lower than soldering temperature, so that they wont be damaged by thermal stress
Top class video, Very Thankful for this one.. helped us to come over the panic and do the things easily at low cost
excellent video. great clear image, and audio. seems like a very sensible approach.
great clear video man. a relief almost as there so much junk out there.
That's pretty cool. Thanks for explaining how to get rid of the bridges.
great vid, clear and very nicely explained
this video is perfect., only remember that when your pcb is very cool it's recomended to use a preheater for this optimal results. , I think is a very very good video.
nice video and nice technique
which microscope does you use in this tutorial?
would you suggest some kind of flux? thanks .
very nice, high quality video! Cheers
don't do this at home...
arra keszulok, hogy 0.2mm 56pin QFN-t beforrasszak, mindjart 2t.. :) ezert kerestem ra, hog ymi a technikaja
:D
@@tamisoft 40 pin this qfn chip, maybe 0.5 mm between legs
@@ivahov55 yes he said 0.5 mm pin spacing.
Great video!
Any recommendations on whether to use low temperature (eg: 138° SN42 BI58) lead-free solder?
I always use leadful solder. What can I say? I don’t feel like buying a new set of metcal
Perfect!
Can I just leave it their without soldering the sides? I mean those are just indicator right? I'm having difficulty soldering specially when pins are higher than 48
Nice video! What flux brand/ref are you using?
+Gran Jere MG Chemicals 8341! Love it.
Thanks!
what kind of applicator are u using for ur flux?
i have problem with 5x5 mm uqfn40 no lead chips
What is your temperature because i use to get black coloration due to overheated on the board. And what is the flux u use?
HowTo DIY homeMade Electronica do go with a reflow technique first preheat the pcb and then go to required temp for the solder you using.
This will surely help prevent the discolouration of your pcb.
if you don't preheat the pcb, there is a big temp gradient loss from the IC to the board and you end up having to apply more heat at higher temperature, which leads to burning the fiber glass pcb. If you preheat you can reach liquid state at lower air pencil temperature because there is much less loss from IC to pcb.
Mooshim Engineering, what brand of flux and solder?
Did I understand right when he said that he put a couple of vias down that he drilled new holes into the board? How can he tell that there are no tracks among the layers?
What is the temperature?
thanks
What is the use flux paste?
are you alife?
www.pcbgogo.com/blog/What_Is_Solder_Flux_And_How_Do_You_Use_It_.html
Perfeito!
when designing pcb they should make longer pads for soldering pins under package.
in my experience with commercial electronics, you do not get the room to do that.
are you the one who makes mooshim meters?
Yup :)
Хорошая пайка, я так же делаю. :)
👍
Sir can you tell me the name of flux that you use?
I wonder how do I desolder QFN40 DrMOS
you can buy the right size square shield little tub with hollow on bottom and 4 tapered walls made by JBC that isolate the QFN from its surrounding, then you do apply the same thermal profile. First ramp, soak, then reflow with hot air pencil. The expensive hot air pencil have a vacuum suction head build inside the pencil head. But if you don't have that, I am guessing, i could be wrong that once you reach eutectic liquidness, you can just shove the IC away, then clean remaining solder with a hot solder removal vacuum tool.
Also tell me the liquid use to remove extra flux
And I guarantee that "Pie" is much easier!
You just got super lucky this time ?
Oo a bluetooth IC :P
lets see this done with all the passive components nearby installed. not so easy
i guess that's the difference between prototype and rework. When building your prototype you can start with the QFNs.
Surface tension will keep the component stay
show de luxo me dis uma coisa vc aqueceu por debaixo da placa
I put it in a toaster oven.
4:40)
No concerns of thermal shock from direct top heating of the IC to the point that solder melts on the leads? No concerns of cold solder joints from moving the component while cooling? No concerns with inactivated flux corroding the board over time?
+Bryon Dahle It's a prototype, meant to verify design functionality and never be sent to customers. So no :)
I mean what else do you recommend to a hobbyist at home
The idea is to minimize temperature gradient at every point on the board near the IC in the presoak stage. You want to reach a uniform temperature. This is key.This is very dooable. You can use a thermocouple taped to the pcb with kastan tape to help you get an idea of pcb temperature while using the HAP. You are trying to replicate the reflow profile with only a preheater and a hot air pencil. When you start the reflow ramp, you start with the pencil high above the IC and work it down. If you do the presoak well you will not shock the IC because there will be low temperature gradient between the IC and the PCB which minimizes heat loss and you will reach liquidity at lower HAP temp. But if you skip preheat, there is a ton of loss and you have to crank up the HAP temperature to reflow and then you will shock and damage the part.
You are right, about you should not mov the part during cooling but when you are above eutectic temperature the phase is liquid and it's ok to move the ic. If you solder is not eutectic type, it will go in a plastic intermediate phase between liquid and solid where there is risk of forming cold joint if you move the part.
just note: always check your datasheet for thermal profile, some parts need to be preheated for a minute or so at lower than soldering temperature, so that they wont be damaged by thermal stress