The presentation is about the heart and soul of any electronic equipment without which the engineering wont reach anywhere. Yes, I am talking about PCB which has made the dream come true.

1. PREPARED BY
UJJWAL KUMAR CHOUBEY
UJJWALCHOUBEY80@GMAIL.COM

2. A printed circuit board (PCB) mechanically supports and
electrically connects electrical or electronic components using
conductive tracks. This is most essential part of any electronic
device, and is used in all daily use equipment from kitchen to
office.

3. BEFORE PCB
• Before printed circuits used in electronics, point
to point construction was used.
• This means some extremely bulky and unreliable
designs that required large sockets and regular
replacement.

4. EVOLUTION OF PCB
• In early 1920s, PCB material could be almost
anything, from Bakelite and Masonite to plain old
thin pieces of wood.
• Holes could be drilled into the material and flat
brass wires would be riveted onto it. It may not
have been pretty, but the concept was there, and it
worked. It was often used in radios and
gramophones at the time.

5. • In1950s and 60s, the types of materials used
for the board was shifting to different resins
and other materials, but they could still only be
printed on a single side.
• The wiring would be printed on one side and
the electrical components would be on the
other.
• It was a much more efficient option than bulky
wiring, so it was starting to see a wider
adoption.
EVOLUTION OF PCB

6. • One of the biggest steps forward came in 1956
when the U.S. Patent Office granted a patent to a
small group of scientists representing the U.S. Army
for the “Process of Assembling Electrical Circuits.”
• At the time, the process involved drawing the wiring
pattern and then photographing it onto a zinc plate.
• This plate could then be used to create a printing
plate for an offset printing press.
• This is what was used to print the wire in acid
resistant ink on the copper foil, which could then be
etched by an acid solution.
EVOLUTION OF PCB

7. TYPES OF PCB’S
Different types of PCBs are used based on the
applications:

8. Single Sided PCB
• Single sided PCBs are the basic type of
circuit boards, which contain only one layer
of substrate or base material. The layer is
covered with a thin layer of metal, i.e.
copper.
• Single sided PCB’s are utilized for volume
production and are low in cost.
• Its applications are, power sensors, relays,
sensors and electronic toys
TYPES OF PCB’S

9. Double Sided PCB
• Double sided PCBs have both the sides featuring
metal conductive layer. Holes in the circuit board
allow the metal parts to be attached from one side to
the other. These PCBs connect the circuits through-
hole technology and surface mount technology.
• The through-hole technology involves inserting
of lead components through the pre-drilled holes
on the circuit board, which are soldered to the
pads on the opposite sides.
• The surface mount technology involves electrical
components to be directly placed on the surface
of the circuit boards.
• Applications, mobile phone system, power
monitoring, test equipment, amplifiers
TYPES OF PCB’S

10. Multi-layer PCB
• Multi-layer PCBs are printed circuit boards,
which comprise more than two copper layers
like 4L, 6L, 8L, etc.
• These PCBs expand the technology used in
double sided PCB’s.
• Various layers of a substrate board and
insulating materials separate the layers in
multi-layer PCBs.
• Multi-layer PCBs offer a high level of design
flexibility.
• These PCBs play an important role in high
speed circuits.
TYPES OF PCB’S

11. Rigid PCB
• Rigid PCBs refer to those types of
PCBs whose base material is
fabricated from a solid material and
which cannot be bent.
• These PCBs are compact, which
ensures the creation of variety of
complex circuitry around it.
• Rigid PCBs offer easy repair and
maintenance, as all the components
are clearly marked. Also, the signal
paths are well organized.
TYPES OF PCB’S

12. Flexible PCB
• Flexible PCBs are constructed on a flexible
base material. These PCBs come in single
sided, double-sided and multilayer formats.
This helps in reducing the complexity within
the device assembly.
• These PCBs help save a lot of space, along
with reducing the overall board weight.
• Flexible PCBs helps in decreasing the board
size.
• These PCBs are designed for working
conditions, where temperature and density is
a main concern.
TYPES OF PCB’S

13. Rigid-Flex- PCB
• Rigid flex PCBs are the combination of
rigid and flexible circuit boards. They
comprise of multiple layers of flexible
circuits attached to more than one rigid
board.
• These PCBs are precision built. Hence, it
is used in various medical and military
applications.
• Being light-weight, these PCB offer 60%
of weight and space savings.
TYPES OF PCB’S

14. High-Frequency PCB
• High-frequency PCBs are used in the
frequency range of 500MHz – 2GHz.
• These PCBs are used in various frequency
critical applications like communication
systems, microwave PCBs, microstrip PCBs,
etc.
TYPES OF PCB’S

15. Aluminum backed PCB
• These PCBs are used in high power
applications, as the aluminum
construction helps in heat dissipation.
• Aluminum backed PCBs are known to
offer high level of rigidity and low level
of thermal expansion, which makes
them ideal for applications having high
mechanical tolerance.
• The PCBs are used for LEDs and power
supplies.
TYPES OF PCB’S

16. MANUFACTURING PROCESS OF PCB
• Base material
• Select the material (Substrate material, Conductor
material, Adhesives, Protective coating) according
to its application. Clean the laminate containing
copper foil and cut the plate as required.
• Circuit pattern
• Prepare the circuit using software (OrCAD, Pads,
Eagle, etc.)
• Print the circuit on a film with an acid resistant ink.
• Clear Ink to show the non-conductive areas
• Black Ink to show the conductive copper traces and
circuits.

17. • Photographing circuit
• Align the photo- sensitive film on board tightly,
that will harden the black path when exposed to
UV light.
• Expose the board and film to UV light. The light
passes through the clear parts of the film,
weekend the copper underneath, and they are
slated for removal.
• Etching circuit
• The process of removing the unwanted copper
the board is dipped into an acidic solution (Conc.
HCL, Conc. H2So4, etc.), and the hardened
photoresist remains intact.
MANUFACTURING PROCESS OF PCB

18. • Drilling
• Holes are bored into the stack board, the holes are
drilled to a hairs-width - the drill achieves 100 microns
in diameter and are done with high precision.
• Surface finish
• The PCB is plated with a solderable finish, depending
on the requirements, which will increase the
quality/bond of the circuit track.
• Testing
• The technician perform an electrical test on the board.
This will confirm the PCB functions and follows the
original blueprint designs.
MANUFACTURING PROCESS OF PCB

19. • Medical - Pacemakers, imaging equipment, drug
delivery systems, wireless controllers.
• Military - Weapons guidance systems,
communication systems, GPS, aircraft, missile-
launch detectors.
• Aerospace - Radar equipment, GPS, radio
communication systems, control, tower systems,
sensors.
• Telecommunication - Base stations, handheld
units, communication satellites, wireless
communication systems, signal processing
systems.
APPLICATION

20. • Automotive - Electronic control module,
transmission controls, LCD displays, comfort
control units, air conditioning systems, music
systems.
• Manufacturing - Test equipment, electrical
switches, industrial automation systems,
control panels, industrial air conditioners, and
CCTV surveillance systems.
• Consumer Appliances - Oven, TV remote
controllers, washing systems, lighting
systems, solar power systems, UV water
purifiers.
APPLICATION