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Hand Soldering SMT Cap ?

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PCB

#62792

Hand Soldering SMT Cap ? | 29 September, 2010

Hi,

i have designed Double sided PCB all SMT Parts are mounted on bottom side and TH on Top Side.

with recent testing we found that the decap needs to be placed closer to IC VDD-GND Pins.

as i can't place TH Parts since i don;t have space on bottom side to place pad near IC.

I want to use SMT Kind of pad and package to mount cap on TOP Side.

the problem is in production it is difficult to solder SMT Package i was thing of 1206 package.

can any one suggest the package or method that can solve my problem. the rule is the package needs to have smt pad and should be able to solder it manually.

thanks for reading......

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#62794

Hand Soldering SMT Cap ? | 29 September, 2010

In trying to understand your situation better, you say, "The problem is in production. It is difficult to solder SMT package. I was thinking of 1206 package."

Please clarify: * What is difficult about hand soldering your SMT part? What is the part? How are you soldering it? What is the solderability protection on the board? Are the pads on the board where you are soldering this part solderable? * Why are you using a SMT part? What is it about a PTH part that makes it unacceptable?

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PCB

#62796

Hand Soldering SMT Cap ? | 29 September, 2010

What is difficult about hand soldering your SMT part?

Production solder All SMT packages by reflow Process and not by hand solder. because they think if they use hand soldering on SMT package- Soldering quality can’t be ensured as this is SMT parts. Manufacture efficiency low when solder by manual.

What is the part? i mean package.

How are you soldering it? All SMT are on bottom side so production is using reflow soldering method for soldering all SMT packages except i want to place ONE SMT CAPACITOR Package 1206 on top side but prodution denying it as they don't want to hand solder SMT PKG. What is the solderability protection on the board? Sorry didn't understand question.

Are the pads on the board where you are soldering this part solderable? Yes, i am using 1206 SMT Cap Footprint.

Why are you using a SMT part? What is it about a PTH part that makes it unacceptable?

Cap has to be physically close as possible to IC and since i don't have space to put PTH Pad or smt pad on BOTTOM Side the only option i see is to place SMT 1206 on top side.

using this forum i want understand if sodering smt by hand is commonly acceptable during production ?

Thanks a lot for reply.

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#62797

Hand Soldering SMT Cap ? | 29 September, 2010

Are the TH parts on the topside hand soldered then? Why not print-place-reflow the topside SMT cap first then run the bottomside through the same process? It is normal, although not preferred to solder SMT parts on by hand. A 1206 should not be difficult to solder by hand.

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PCB

#62799

Hand Soldering SMT Cap ? | 29 September, 2010

TH Parts are hand loaded - some are wave soldered and some hand soldered.

smt 1206 on top side can be reflowed as you suggested but it's addition of one more step of reflow cycle in process for production. and i think that's why they are reluctant on this.

Appreciate your feedback.

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#62802

Hand Soldering SMT Cap ? | 30 September, 2010

Add paste, place part, and then use a heatgun to reflow the paste.

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#62813

Hand Soldering SMT Cap ? | 30 September, 2010

Sure. Doing what you're talking about will blank their process metrics, regardless if it's done manually or by machine.

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#62830

Hand Soldering SMT Cap ? | 3 October, 2010

Hi. there's no other way to do except hand solder the top side cap or using hand print hand place method during SMT process. otherwise you will have to spend more time just to set up this process. bottom line is you have to install this one cap first then flip around to do the bottom side.this is to eliminate your difficulty in Hand soldering the one cap after T/H. if your concern that this one cap will drop during reflow then either you have to adjust the bottom temp or use the epoxy dispenser.

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