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Engineering Workshop
Lab Session 06
NED University of Engineering & Technology – Department of Computer & Information Systems Engineering
Lab Session 06
OBJECT
Demonstrating Printed Circuit Boards.
THEORY
In this lab we are going to implement a circuit on PCB( Printed Circuit Board). We are going to
use the concepts built in the previous lab session regarding different aspects of PCB design.
You have already implemented the circuit mentioned below in Fig 6.1 using breadboard /
veroboard in previous lab session. We are going to implement the very same circuit with PCB in
this lab session.
VCC 5V To +15V
R1
8
2
4
8
V (output)
R2
OUT
3
6
555
2
+
C
1
Figure 6.1
Patterning (etching)
The vast majority of printed circuit boards are made by bonding a layer of copper over the entire
substrate, sometimes on both sides, (creating a "blank PCB") then removing unwanted copper
after applying a temporary mask (e.g. by etching), leaving only the desired copper traces. A few
PCBs are made by adding traces to the bare substrate (or a substrate with a very thin layer of
copper) usually by a complex process of multiple electroplating steps. The PCB manufacturing
method primarily depends on whether it is for production volume or sample/prototype quantities.
Circuit Schematics Imprint
The print of the circuit depends on the requirement which can be categorize as follow:
 Commercial
o silk screen printing–the main commercial method
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