seminar code
09-08-2014, 10:33 AM
MAKING PRINTED CIRCUIT BOARD
[attachment=66775]
INTRODUCTION
Making a Printed Circuit Board is the first step towards building electronic equipment by any electronic industry. A number of methods are available for making P.C.B., the simplest method is of drawing pattern on a copper clad board with acid resistant (etchants) ink or paint or simple nail polish on a copper clad board and do the etching process for dissolving the rest of copper pattern in acid liquid
PROCEDURE
The first and foremost in the process is to clean all dirt from copper sheet with say spirit or trichloro ethylene to remove traces grease or oil etc. and then wash the board under running tap water. Dry the surface with forced warm air or just leave the board to dry naturally for some time.
Making of the P.C.B. drawing involves some preliminary consideration such as thickness of lines/ holes according to the components. Now draw the sketch of P.C.B. design (tracks, rows, square) as per circuit diagram with the help of nail polish or enamel paint or any other acid resistant liquid. Dry the point surface in open air, when it is completely dried, the marked holes in P.C.B. may be drilled using 1Mm drill bits. In case there is any shorting of lines due to spilling of paint, these may be removed by scraping with a blade or a knife, after the paint has dried.
After drying, 22-30 grams of ferric chloride in 75 ml of water may be heated to about 60 degree and poured over the P.C.B. , placed with its copper side upwards in a plastic tray of about 15*20 cm. Stirring the solution helps speedy etching. The dissolution of unwanted copper would take about 45 minutes. If etching takes longer, the solution may be heated again and the process repeated. The paint on the pattern can be removed P.C.B. may then be washed and dried. Put a coat of varnish to retain the shine. Your P.C.B. is ready.
PRECAUTION
Add Ferric Chloride (Fecl3) carefully, without any splashing. Fecl3 is irritating to the skin and will stain the clothes.
2. Place the board in solution with copper side up.
3. Try not to breathe the vapours. Stir the solution by giving see-saw motion to the dish and solution in it.
4. Occasionally warm if the solution over a heater-not to boiling. After some time the unshaded parts change their colour continue to etch. Gradually the base material will become visible. Etch for two minutes more to get a neat pattern.
5. Don't throw away the remaining Fecl3 solution. It can be used again for next Printed Circuit Board P.C.B.
USES
Printed Circuit Board are used for housing components to make a circuit for compactness, simplicity of servicing and case of interconnection. Thus we can define the P.C.B. as : Prinked Circuit Boards is actually a sheet of bakelite (an insulating material) on the one side of which copper patterns are made with holes and from another side, leads of electronic components are inserted in the proper holes and soldered to the copper points on the back. Thus leads of electronic components terminals are joined to make electronic circuit.
In the boards copper cladding is done by pasting thin copper foil on the boards during curing. The copper on the board is about 2 mm thick and weights an ounce per square foot.
The process of making a Printed Circuit for any application has the following steps (opted professionally):
PRINTED CIRCUIT BOARD
Printed circuit boards are used for housing components to make a circuit, for comactness, simplicity of servicing and ease of interconnection. Single sided, double sided and double sided with plated-through-hold (PYH) types of p.c boards are common today.
Boards are of two types of material (1) phenolic paper based material (2) Glass epoxy material. Both materials are available as laminate sheets with copper cladding.
Printed circuit boards have a copper cladding on one or both sides. In both boards, pasting thin copper foil on the board during curing does this. Boards are prepared in sizes of 1 to 5 metre wide and upto 2 metres long. The thickness of the boards is 1.42 to 1.8mm. The copper on the boards is about 0.2 thick and weighs and ounce per square foot
[attachment=66775]
INTRODUCTION
Making a Printed Circuit Board is the first step towards building electronic equipment by any electronic industry. A number of methods are available for making P.C.B., the simplest method is of drawing pattern on a copper clad board with acid resistant (etchants) ink or paint or simple nail polish on a copper clad board and do the etching process for dissolving the rest of copper pattern in acid liquid
PROCEDURE
The first and foremost in the process is to clean all dirt from copper sheet with say spirit or trichloro ethylene to remove traces grease or oil etc. and then wash the board under running tap water. Dry the surface with forced warm air or just leave the board to dry naturally for some time.
Making of the P.C.B. drawing involves some preliminary consideration such as thickness of lines/ holes according to the components. Now draw the sketch of P.C.B. design (tracks, rows, square) as per circuit diagram with the help of nail polish or enamel paint or any other acid resistant liquid. Dry the point surface in open air, when it is completely dried, the marked holes in P.C.B. may be drilled using 1Mm drill bits. In case there is any shorting of lines due to spilling of paint, these may be removed by scraping with a blade or a knife, after the paint has dried.
After drying, 22-30 grams of ferric chloride in 75 ml of water may be heated to about 60 degree and poured over the P.C.B. , placed with its copper side upwards in a plastic tray of about 15*20 cm. Stirring the solution helps speedy etching. The dissolution of unwanted copper would take about 45 minutes. If etching takes longer, the solution may be heated again and the process repeated. The paint on the pattern can be removed P.C.B. may then be washed and dried. Put a coat of varnish to retain the shine. Your P.C.B. is ready.
PRECAUTION
Add Ferric Chloride (Fecl3) carefully, without any splashing. Fecl3 is irritating to the skin and will stain the clothes.
2. Place the board in solution with copper side up.
3. Try not to breathe the vapours. Stir the solution by giving see-saw motion to the dish and solution in it.
4. Occasionally warm if the solution over a heater-not to boiling. After some time the unshaded parts change their colour continue to etch. Gradually the base material will become visible. Etch for two minutes more to get a neat pattern.
5. Don't throw away the remaining Fecl3 solution. It can be used again for next Printed Circuit Board P.C.B.
USES
Printed Circuit Board are used for housing components to make a circuit for compactness, simplicity of servicing and case of interconnection. Thus we can define the P.C.B. as : Prinked Circuit Boards is actually a sheet of bakelite (an insulating material) on the one side of which copper patterns are made with holes and from another side, leads of electronic components are inserted in the proper holes and soldered to the copper points on the back. Thus leads of electronic components terminals are joined to make electronic circuit.
In the boards copper cladding is done by pasting thin copper foil on the boards during curing. The copper on the board is about 2 mm thick and weights an ounce per square foot.
The process of making a Printed Circuit for any application has the following steps (opted professionally):
PRINTED CIRCUIT BOARD
Printed circuit boards are used for housing components to make a circuit, for comactness, simplicity of servicing and ease of interconnection. Single sided, double sided and double sided with plated-through-hold (PYH) types of p.c boards are common today.
Boards are of two types of material (1) phenolic paper based material (2) Glass epoxy material. Both materials are available as laminate sheets with copper cladding.
Printed circuit boards have a copper cladding on one or both sides. In both boards, pasting thin copper foil on the board during curing does this. Boards are prepared in sizes of 1 to 5 metre wide and upto 2 metres long. The thickness of the boards is 1.42 to 1.8mm. The copper on the boards is about 0.2 thick and weighs and ounce per square foot