A Printed Circuit Board or PCB is Mechanical Support & electrically wired the electronic components using the copper (conductive path) which is made by etching copper clad. PCB is also called as printed Wired Board (PWB). The PCB without component is raw PCB & PCB with component is called printed circuit board assembly it means the raw PCB is assembled with electronics components.
Now a day’s PCB (raw) become very inexpensive especially Single sided Board (SSB) & Double Sided Board (DSB). Multi layers PCB are still costly due to its high setup charges.
Single Sided Board (SSB)
The Printed Circuit Board which has only one track (copper) layer is called SSB.
Double Sided Board (DSB)
The Printed Circuit Board which has two track (copper) layer is called DSB.
Multi layer Board
The Printed Circuit Board which has more than two copper layers.
Material Used for Printed Circuit Board (PCB)
Conductive Layer is basically is of thin copper foil the base is of glass epoxy (insulating materials) some types are as bellow.
From above the first two are widely used for mass production of printed circuit board.
Ø The Last one is using for prototype production of printed circuit board.
Prototype PCB means the limited nos. of PCB which is for R & D purpose of new product or modification of existing product.
The cooper etching (Photo etching) method is widely is used by large scale PCB manufacturing Companies all over world.
Ø Screen printing method is cost saving, but it compromise with quality,also fine Printed Circuit Board with below 10 mil track & same spacing is very hard to achieve with this method. But still some companies are using this to manufacture the low cost Printed Circuit Boards.
Ø PCB milling is adopted recently for quick turn Printed Circuit Boards manufacturing. The Printed Circuit Boards are milled on cnc machine mechanically with routers (end mill). These methods save lot of time. But this method is not useful for mass production of Printed Circuit Boards.
Photo etching
With the below we will look the steps involved
for Printed Circuit Board manufacturing with photo
etching methods.
Lets Start from beginning how the Printed Circuit
Boards are manufactured.
Suppose I have requirement of Printed Circuit Board
I will search the Printed Circuit manufacturer in my region
with competitive rates.
Select one from them.
First I have to send the gerber files to him for quotation
in that I have to mention few things about my requirement
Such as Pcb thickness, Pcb finish copper, Masking,
silk screen color ( By default it is masking PISM green,
silk is white), HAL, Lead free, Delivery time.
When this data reach to Printed Circuit Board
manufacturer he study the data & give the
quotation.
Factors which play vital role deciding the price of
Printed Circuit Board.
Quantity of Printed Circuit Boards.
Minimum track , spacing & minimum drill diameter
( Keep minimum track thickness & spacing between to connection 6 to 8 mill to reduce cost )
Panelization includes step & repeat. The data is multiple &
venting & theiving bars are added around borders of panel.
To be continued......................
After completion of the software work the gerber data is generated for required films. The films (plots) required to be plotted. We recommend get your plots from qualified service beuro if in house laser photoplotting facility is not available.
Benefits of outsourcing,
You will have to pay only for your plots (Rates are very competitive), Need not worry about quality if choose right service beuro (We recommend choose service beuro which have experience in Printed circuit board). No extra cost for Laser Photoplotter (approx USD 10K TO 20K), Save cost for special employee for the photoplotting department (employee salary, bonus & other facilities). If you have any problem with quality of plots service beuro will replace it free of cost.
We strongly recommend get your Photoplots from Laser Photoplotting Beuro only as after all it is matter of quality.
Some service beuro provide free DRC service which is another great benefit. We get appreciation from our clients for this service many times.
For Printed Circuit Board Manufacturers
Our belief that client want his product quick but he will not happy at all if he get rejected board quickly. This will cause more delay. We think PCB manufacturers should plan their work & do not hurry to just finishing work as early as possible. The clients are totally depending on you when he gives his work to you. Give appropriate delivery time. (Such as for SSB: - 2 days, DSB 3 to 4 days for MLB 10 days). We think client will have not bothered if PCB manufacturer take one more day to deliver the PCB (Ok PCB). Golden Rule of R.T.O ‘it is better to delay than accidents’ here we can say ”it is better to delay than rejection.
Let’s move on
Films required for Single Side Board are as below
1) Bot side 2) Bot side Mask (sometime called as bottom resists) 3) Top side silk.
Films required for Double Side Board are as below
1) Top side 2) Bot side 3) Top side mask 4) Bot side mask 5) Top side silk 6) Bot side silk.
Films required for Multilayer Board (4 layer) are as below
1) Top side 2) Inner one 3) Inner two 4) Bot side 5) Top side Mask 6) Bot side mask 7) Top side silk 8) Bot side silk.
In multilayer PCB as no. of layer increases no of film increases.
