Printed circuit boards are at the heart of almost every type of electrical goods today, and yet the lay person has only the vaguest impression of what they actually are, much less how they are assembled by a printed circuit board manufacturer. As they have become an integral part of daily life, it is intriguing to find out more about these gadgets, and how they come to be.
Some examples of products containing printed circuit boards (PCBs for short) are televisions, computers, microwave ovens and mobile phones, although most electric appliances nowadays contain some sort of PCB. Electrical goods can be made without using PCBs, but this technique has proved to be the cheapest and fastest way.
All PCBs have a few basic purposes in common, namely to provide a surface for components to be mounted on, and also to provide the appropriate conductors which connect them together. The two most popular basic starting points for PCBs are called laminates, and copper-clad laminates.
To make a PCB, cloth or paper are layered with resin to create rigid, slim boards. During this process, the materials are warmed and pressurized for optimum results. These boards are called laminates, and by themselves they cannot conduct electricity. For this purpose, either the entire board is coated with copper (as in the copper-clad laminate), and any that is unwanted is subsequently removed, or else the user adds copper only as desired.
The process where copper is added only as required is quite elaborate. The more popular method utilizes PCBs which already have a copper layer. In this approach, the unwanted copper is eaten away by chemicals, leaving only the conductors needed by the user. Removing the copper in this manner is known as etching.
The copper required for the circuit is protected from the etching chemicals in various ways, but the most popular method involves depositing special ink, which is resistant to the chemicals, on the areas to be kept. This is usually done using silk screen printing.
Etching at its most simple could consist of marking out the copper connections needed on the laminate board with the chemical resistant ink, and then steeping the board in an etching solution, which will eat away the unwanted copper. In practice, this method is slow, and various refinements have been devised to speed things along. Mainly this involves agitating the solution and the board to help remove the dissolved copper. The main method of this nowadays is spray etching. Sprays are used to apply the etching chemicals, while the temperature, spray configuration and direction can all be controlled to allow optimum efficiency.
Before components can be added to the PCB, holes must be drilled for each one. Due to the properties of the laminate board, steel drill bits would be blunted very quickly, resulting in tearing of the fine copper connectors. This problem is overcome by using special tungsten carbide drill bits.
The processes looked at here are some of the most common practices used by the printed circuit board manufacturer. PCBs have been made industrially since the 40s, and through the decades many manufacturing techniques have been explored. But after all that time, laminates, etching, silk screen printing and the use of tungsten carbide drill bits still remain at the forefront of PCB manufacture.
Some examples of products containing printed circuit boards (PCBs for short) are televisions, computers, microwave ovens and mobile phones, although most electric appliances nowadays contain some sort of PCB. Electrical goods can be made without using PCBs, but this technique has proved to be the cheapest and fastest way.
All PCBs have a few basic purposes in common, namely to provide a surface for components to be mounted on, and also to provide the appropriate conductors which connect them together. The two most popular basic starting points for PCBs are called laminates, and copper-clad laminates.
To make a PCB, cloth or paper are layered with resin to create rigid, slim boards. During this process, the materials are warmed and pressurized for optimum results. These boards are called laminates, and by themselves they cannot conduct electricity. For this purpose, either the entire board is coated with copper (as in the copper-clad laminate), and any that is unwanted is subsequently removed, or else the user adds copper only as desired.
The process where copper is added only as required is quite elaborate. The more popular method utilizes PCBs which already have a copper layer. In this approach, the unwanted copper is eaten away by chemicals, leaving only the conductors needed by the user. Removing the copper in this manner is known as etching.
The copper required for the circuit is protected from the etching chemicals in various ways, but the most popular method involves depositing special ink, which is resistant to the chemicals, on the areas to be kept. This is usually done using silk screen printing.
Etching at its most simple could consist of marking out the copper connections needed on the laminate board with the chemical resistant ink, and then steeping the board in an etching solution, which will eat away the unwanted copper. In practice, this method is slow, and various refinements have been devised to speed things along. Mainly this involves agitating the solution and the board to help remove the dissolved copper. The main method of this nowadays is spray etching. Sprays are used to apply the etching chemicals, while the temperature, spray configuration and direction can all be controlled to allow optimum efficiency.
Before components can be added to the PCB, holes must be drilled for each one. Due to the properties of the laminate board, steel drill bits would be blunted very quickly, resulting in tearing of the fine copper connectors. This problem is overcome by using special tungsten carbide drill bits.
The processes looked at here are some of the most common practices used by the printed circuit board manufacturer. PCBs have been made industrially since the 40s, and through the decades many manufacturing techniques have been explored. But after all that time, laminates, etching, silk screen printing and the use of tungsten carbide drill bits still remain at the forefront of PCB manufacture.
About the Author:
Discover the best printed circuit board manufacturer for your budget by visiting our official website at www.becman.com today. To know more about our capabilities and our prices, check out http://www.becman.com .
No comments:
Post a Comment