Publications - October 2015
Ordering PCB – make the most out of your spending
PCB is an industrial product and when people request quote from manufacturer, they believe the price is competitive and no further discussion is needed. In most cases, this is true and manufacturers quote correctly against the way inquiry was sent. What differentiates the best manufacture with an ordinary manufacture is their ability to judge the inquiry correctly and then not only offer the competitive but an optimum solution.
Now, what is an optimum solution? It is a strategy that avoids long term loss for short term gain and offers a balanced outcome. Therefore, as a customer, it is important to know PCB manufacturers’ limitations, pricing patterns, key advantages etc. so that correct inquiry can be generated. Missing information can lead to wrong pricing.
Since every manufacturer works little bit differently, in this article, we have considered QualiEco Circuits’ manufacturing standards to explain some of the important aspects of costing.
1. Design Characteristics
It is important to know which design requirements are standard and attract no extra cost against one that are special and cost extra. Following table will help you distinguish between such standard and non-standard design requirements:
|PCB Specifications||QualiEco - Standard||QualiEco - Non-Standard|
|Thicker laminate||0.8mm to 1.6mm||0.4mm, 2.0mm & above|
|Thicker copper||1oz (35µ)||2oz and above|
|Via Hole Size||0.25mm and above||>0.1mm & <0.2mm|
|Track Width/Spacing||5mil (0.127mm) and above||>3mil (0.076mm) & <5mil (0.127mm)|
|Solder mask colour||Green, Red, Blue, White, Black||Red, Blue, White, Black (for high vol)|
|Overlay colour||White, Yellow||Yellow (for high vol)|
|Surface Finish||Leaded or Lead-free HASL||Immersion silver/gold/tin, OSP|
|High Tg Laminate||Tg 130°-135°||Tg 150°-180°|
|Peelable Solder Mask||No||Yes|
|No “X” out panels||No||Yes|
|Via Tenting||Using solder resist (not guaranteed 100%)||100% guaranteed|
|Via Plugging||Using HASL (not guaranteed 100%)||100% guaranteed (silicon plugging)|
|Plated Rout/PTH cut out||No||Yes|
QualiEco Circuits measure PCB manufacturing volume in sq.meter and classify each inquiry and its relevant pricing based on this criterion. There are manufactures who also measure volume in sq.inch or sq.cm.
How should one calculate volume? Let’s say PCB size is 100mm x 150mm and required quantity is 50 pieces, the volume would be 0.75 sq.meter (i.e. 0.1 x 0.15 x 50).
QualiEco classifies volume from low to medium to high using following range -
0-1 sq.meter – Pure Prototypes and/or very low volume (established designs)
1-10 sq.meter – Low to medium volume (established designs)
> 10 sq.meter – High volume (established designs)
Each volume classification comes with unique manufacturing set up, lead time, cost etc. Therefore, if the design is not a pure prototype and future repeat order is expected, it is very important to inform us the approximate quantity expected in future run. This information will help us judge the correct volume classification for your requirement, which will benefit you in a longer run.
3. Engineering Tooling Cost / Fix Cost / Set up Cost (one off)
The major cost in PCB manufacturing for small to low volume production is one off engineering tooling cost, which is also known as fix cost or set up cost. For large volume production, one off engineering cost is normally not a critical cost factor because it amortized among higher quantity.
This engineering tooling cost consists of two parts (a) film work and drill set up cost (b) e-testing cost. The major part that drives the tooling cost is the method used for e-testing.
If e-testing is performed only on flying probe machine, the tooling cost will be less expensive but the time consumed for testing will always be higher. One-off prototypes and very small volume orders are normally tested on flying probe to reduce the set up cost.
If e-testing is performed using bed of nail technology, the manufacture will be required to prepare a dedicated test jig, which costs a lot. QualiEco doesn’t charge any extra set up cost at the time of repeat order, except when change in quantity result into change in volume classification.
4. Other Aspects
a) Unconventional layer construction for multi-layer PCBs
Many designs require unconventional layer construction, which is not possible without adding a dummy layer during manufacturing. Because of this, 4 layer designs could be priced as 6 or even 8 layer designs. It is good idea to get your layer construction checked so that you can control your prices and stay in budget.
b) Multi-design orders
For pure prototype reason, if you want to manufacture more than one design to save cost, it is not a bad idea. QualiEco allows customers to club more than 1 design (up to maximum 5-6 per set up) and supply single design data for production. Each extra design will be charged a very nominal fee instead of whole new engineering set up. The only disadvantage is that you will have to order all designs together in same proportion for all repeat runs.
c) Shipping Cycle
Just by placing order on certain day of the week by daily cut off time could help saving unnecessary express turnaround cost. For example, placing order with QualiEco on Monday or Friday morning could save 1-2 working days in overall lead time.
If you want to benefit from our monthly Technical Guide, please subscribe here.
PCB Design Tips
When designing a PCB, try to limit the amount of draws you use. Draws use a lot of memory and slow the programming time. Use a flash for pads instead.
We have capability to manufacture and assemble Single Sided/Layer (SS), Double Sided/Layer (DS-NPTH & DS-PTH) and MultiLayer (up to 32 layers) PCBs with RoHS as an option.
Need to know more about
What our client says?
QualiEco Circuits Pty Ltd has the potential to be an excellent supplier to us! We appreciate the quality of service and support that we receive from QualiEco Circuits. Always deliver what is promised.Susan Chuard
Quality Assurance Supervisor