Solder Tinned Pads vs Gold Plated Pads - The Importance of Selecting the Proper Surface Finish

PCB designers must be selective in their choice of surface finish. If a designer chooses ENIG, their pads will not be tinned with solder, they will instead be gold plated.

It is recommended that designers of PCBs consider what their desired result is, research the options, and make the appropriate choice for their surface finish.

The solution for designers who want solder tinned pads is either HASL or LF-HASL as a surface finish. Things to consider when deciding which surface finish to select include RoHS compliance, shelf life, protection against oxidization and corrosion, and solder-ability. Of course there are many options for surface finish, but HASL and LF-HASL are the only surface finishes that will yield the desired effect if a designer wants solder tinned pads.

One benefit of selecting HASL as the surface finish while fabricating PCBs is all of the through holes get tinned as the board is immersed in molten solder. This provides excellent shelf life and solder-ability. Unfortunately, HASL does not comply with the RoHS directive because the solder used contains lead. LF-HASL is RoHS compliant, but it is otherwise equivalent to HASL in terms of both cost effectiveness and required time.

ENIG provides excellent protection against corrosion and oxidization as well as superb conductivity, while also having the shelf life and solder-ability possible with HASL and the RoHS compliance possible with LF-HASL. This is because the nickel plated copper traces of the PCB have gold deposited on them through an electrolytic process. ENIG is also very cost effective and does not require any additional process time as compared to HASL or LF-HASL.

It is recommended that designers choose ENIG as their surface finish because it is by far the best of the three. However, if the designer is insistent on solder tinned pads, then LF-HASL is recommended over HASL because it is RoHS compliant and completely lead-free. Bittele Electronics Inc. follow the RoHS directive and encourages clients to use lead-free surface finishing materials by making it the same price. Special orders for HASL can be accommodated at the client’s request.

SMOBC – Solder Mask Over Bare Copper

Solder Mask Over Bare Copper (SMOBC) is one of the primary processes of modern PCB fabrication. It is done to ensure that the traces on the PCB have good electrical isolation and to prevent oxidization and short circuits during soldering. The SMOBC process occurs in the early stages of PCB fabrication.

Keywords:

SMT Reflow Oven, Lead free Reflow Oven, Reflow Oven Manufacturer, LED reflow oven, PCB Reflow Oven, Nitrogen Reflow Oven, Dual Rail Reflow Oven, China Reflow Oven, wave soldering machine, Dual Rail Wave Soldering Machine, Nitrogen Wave Soldering Machine, Wave Soldering Machine Manufacturer.

Flason Electronic Co.,ltd provide a full SMT assembly line solutions, including SMT Reflow Oven,  Wave Soldering Machine,  Pick and Place Machine,  SMT Stencil Printer,  SMT AOI SPI Machine,  SMT Reflow Oven,  SMT Peripheral Equipment,  SMT Assembly line,  SMT Spare Parts  etc any kind SMT machines you may need, please contact us for more information: wechat whatsapp:+8613691605420, Skype: flasonsmt, Email: sales@flason-smt.com
FAQ
1) This is the first time I use this kind of machine, is it easy to operate?
There is English manual or guide video that show you how to use machine.
If you still have any question, please contact us by e-mail / skype/ phone /trademanager online service.
2) If machine have any problem after I receive it, how can I do ?
Free parts send to you in machine warranty period.
If the part is less than 0.5KG, we pay the postage.
If it exceeds 0.5KG, you need to pay the postage.
3) MOQ ?
1 set machine, mixed order is also welcomed.
4) How can I buy this machine from you? ( Very easy and flexible !)
A. Consult us about this product on line or by e-mail.
B. Negotiate and confirm the final price , shipping , payment methods and other terms.
C. Send you the proforma invoice and confirm your order.
D. Make the payment according to the method put on proforma invoice.
E. We prepare for your order in terms of the proforma invoice after confirming your full payment.
And 100% quality check before shipping.
F.Send your order by air or by sea.
5)Why choose us ?
A. Gold supplier on Alibaba !
B. Trade assurance to US$54,000 !
C. Best price & Best shipping & Best service !