The Printed Circuit Board Explained

Printed Circuit Board, or PCB, has revolutionized thepurpose of circuit. Examining which components to use
electronics industry. Invented in the 1930s, it has comeis best dealt in an encyclopedia series. This leaves
to be used in every imaginable electronic gadget. Thislaminate boards and traces. Production costs, working
article explains the importance of these boards, andefficiency and operating cost of the finished circuit, all
examines their benefits and manufacturing options.depend on these elements.
Why Use A PCB? What Can It Be Used For?Of the several materials used for the boards, six are
Before delving into the details, it's important for you tothe most widely manufactured: FR-1, FR-2, FR-3, FR-4,
know the possible applications of Printed circuit boards,CEM-1 and CEM-3. "FR" stands for "flame retardant".
and why you should use them (i.e., what theirFR 1, 2 and 3 are essentially the same, with only minor
advantages are).differences in properties. They are not suited for
What can you use them for? Absolutely everything!building multilayer boards. The same is true for CEM-1.
There's virtually no electronic device that can't be builtFR-4 and CEM-3 are two laminates that can be used
using PCBs. Battery-operated toys, cell phones, musicfor multilayer boards. Of the two, FR-4 is more widely
players, TVs, computers, automobiles, aircraft - almostmanufactured, and hence is cheaper. It can be used
everything that uses some sort of electronics, makesfor single and multilayer boards, and has excellent
use of them.thermal tolerance up to 130°C.
Whether you're a hobbyist building a toy, a studentCopper is the most commonly used material for
doing science-project, or an appliance-makertraces. Simple methods involve plating the entire board
manufacturing millions of devices, the use of printedwith copper, and then etching away unnecessary
boards offer benefits.areas through a mask (stencil) to leave the required
Firstly, a PCB is much smaller than other types oftraces. More complex methods allow traces to be
circuits. Its reduced size is an extremely importantadded on to a bare board. Each approach has
aspect to its overall production process. In addition, aassociated pros and cons.
printed circuit greatly reduces the need for wires. ThisSome boards require the use of gold for sensitive,
improves the appearance of the final circuit andlow-voltage applications or lead-free (RoHS)
enhances durability. For mass-producers ordering incompliance. Copper traces usually demand the use of
large production, it's the cheapest method, offeringa nickel barrier layer before gold-plating. This is to
huge cost benefits.prevent gold from migrating into the copper.
What are the Key Design Considerations whenIndiscriminate use of nickel can result in huge losses to
making a PCB?impedance.
There Are Three Main Elements:If you want to develop a custom PCB, it's
* A laminate board.recommended that you first spend a little time
* The components mounted on the board.understanding the basics of PCB design. There are
* Traces that serve as the "wires" connectingseveral detailed guides and tutorials. Also, design and
components and forming the circuit.simulation software are available to help you test your
The actual components used depend entirely on thedesign before you make a PCB Prototype.