Designing Printed Circuit Board
(PCB )
(Tutorial Five)
Computer and Information Engineering Lab II
ECE 3102 & ECE 4102
‫ب ز ْدني ِّ ِّع ْلما ً َو ْر ُز ْقني ِّ فَ ْهما‬
ِّ ‫َر‬
My Lord! Advance me in Knowledge and true understanding .
Laboratory:
Mechatronics Workshop, Room# E2-2-13.12
‫ب ز ْدني ِّ ِّع ْلما ً َو ْر ُز ْقني ِّ فَ ْهما‬
ِّ ‫َر‬
My Lord! Advance me in Knowledge and true understanding .
2
Contents
Basic PCB Skills and Tools.
PCB design using Crocodile.
PCB design using Eagle.
3
Basic PCB Skills and Tools
Construction of Electronics Projects
Need to know about……
•
•
•
•
•
Types of Circuit Board .
Soldering Guide.
Tools required for electronics.
Starter kit of components.
Making a workbench for electronics.
4
Basic PCB Skills and Tools
Types of Circuit Board
 Breadboard
 Stripboard
 Printed Circuit Board
Breadboard
Stripboard
Printed Circuit Board
5
Basic PCB Skills and Tools
Types of Circuit Board (Con.)
Breadboard
 Temporary use, Normally for testing purpose.
 No soldering required .
 This is a way of making a temporary circuit. No soldering is required and all
the components can be re-used afterwards. It is easy to change connections
and replace components. Almost all the Electronics Club projects started life
on a breadboard to check that the circuit worked as intended.
Breadboard
6
Basic PCB Skills and Tools
Types of Circuit Board (Con.)
Stripboard
 Permanent,
 Soldered .
 Stripboard has parallel strips of copper track on one side. The strips are 0.1"
(2.54mm) apart and there are holes every 0.1" (2.54mm). Stripboard
requires no special preparation other than cutting to size. It can be cut with a
junior hacksaw, or simply snap it along the lines of holes by putting it over
the edge of a bench or table and pushing hard.
Stripboard
7
Basic PCB Skills and Tools
Types of Circuit Board (Con.)
Printed Circuit Board


Permanent, soldered .
Printed circuit boards have copper tracks connecting the holes where the
components are placed. They are designed specially for each circuit and
make construction very easy. However, producing the PCB requires special
equipment so this method is not recommended if you are a beginner unless
the PCB is provided for you.
Printed Circuit Board
8
Basic PCB Skills and Tools
Working With PCB
 Single sided layer
• Positive board & Negative board
A sample of positive board
A sample of negative board
the desired circuit will be the
one with black color.
the desired circuit will be the
one with white color.
9
Basic PCB Skills and Tools
Working With PCB (Con.)
10
Basic PCB Skills and Tools
Working With PCB (Con.)
11
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 1
1.
Circuit
Schematic
diagram
PCB Layout
12
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 2
 When the PCB layout (Using software) is finished it
is printed on a Transparent Paper and
becomes a PCB mask.
13
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 3




PHOTO-RESIST BOARD is a
piece of glass reinforced
plastic.
One of the sides is copper
clad with photosensitive
coating.
When the plastic film is
peeled back this sensitive
coating is revealed.
After processing this will
be the PCB.
14
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 4




The PCB mask (transparent
page) is placed underneath
the
photo-resist
board,
touching the sensitive surface.
The plastic film must be
removed.
PCB mask and board are then
transferred to the UV light
Box.
Be careful to ensure that the
PCB mask is the right way up,
otherwise when the circuit is
etched you will discover that
the tracks are also the wrong
way round.
15
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 5


The lid is shut and the box
switched on.
The photo-resist board, with
PCB mask are left underneath
the lid for 2 minutes (120 sec.)
Note: for negative board, the exposure will be for 25 seconds
16
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 6 & 7




The photo-resist board is then
placed in a tank filled with
developer solution.
It is important that the board is
only left in the developer for
approximately ten seconds.
When the board is taken out of
the developer it must be washed
in clean water before transferring
to the etching tank.
Always use plastic tongs or
gloves.
17
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 6 & 7


The etchant used is Ferric
Chloride.
This solution slowly etches
away the unwanted copper,
leaving the tracks only.
◦ At this stage it is important to
keep checking that the PCB is
completed

If it is left in the tank too
long the copper tracks will
also be removed or damaged.
18
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 8 & 9


The last stage is drilling the
holes for the components. A
small PCB drill is used for
this purpose.
Again care is needed as a
good PCB can be ruined by
careless drilling.
19
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 10
Soldering Techniques
1. Use a soldering iron in good condition. Inspect the tip
to make sure that it is not past good operation. If it
looks in bad condition it will not help you solder a good
joint. The shape of the tip may vary from one soldering
iron to the next but generally they should look clean
and not burnt.
2. A PCB eraser is used to remove any film from the
tracks. This must be done carefully because the film
will prevent good soldering of the components to the
PCB. The tracks can be checked using a magnifying
glass. If there are gaps in the tracks, sometimes they
can be repaired using wire but usually a new PCB has
to be etched.
20
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 10
Soldering Techniques (Con.)
3. Place the PCB, with its components in position, in the bull clip. This will steady the
PCB when you try to use the soldering iron.
4. The heated soldering iron should then be placed in contact with the track and the
component and allowed to heat them up. Once they are heated the solder can be
applied. The solder should flow through and around the component and the track
21
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 10
Soldering Techniques (Con.)
5. Having completed soldering the circuit the
extended legs on the components need to be
trimmed using wire clippers. The circuit is now ready
for testing.
Below are some of the warning symbols that appear on etchants and ferric
chloride solutions. They are present to warn the user of their potential danger if
mishandled. Why should etchants and solutions such as ferric chloride be handle
with great care ?
22
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 11
Checking & Testing
23
Basic PCB Skills and Tools
Working With PCB (Con.)
Step 11
Checking & Testing (Con.)
24
Basic PCB Skills and Tools
Working With PCB (Con.)
Finally
The Product
25
Basic PCB Skills and Tools
Tools Required for Circuit Construction
Soldering iron



A soldering iron is a hand tool used in soldering. It supplies heat to melt
the solder so that it can flow into the joint between two work-pieces.
A soldering iron is composed of a heated metal tip and an insulated
handle. Heating is often achieved electrically, by passing an electric current
through a resistive heating element.
The iron's power rating should be 15 to 25W and it should be fitted with
a small bit of 2 to 3mm diameter.
26
Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
Soldering iron stand
 You must have a safe place to put the iron when you are not holding it.
 The stand should include a sponge which can be dampened for cleaning the
tip of the iron.
27
Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
De-soldering pump (solder sucker)
 A tool for removing solder when de-soldering a joint to correct a mistake or
replace a component.
28
Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
Reel of solder
 The best size for electronics is 22swg (swg = standard wire gauge).
29
Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
Cutters
 For trimming component leads close to the circuit board.
30
Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
Small pliers
 Usually called 'snipe nose' pliers, these are for bending component leads
etc. If you put a strong rubber band across the handles the pliers make a
convenient holder for parts such as switches while you solder the contacts.
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Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
Small flat-blade screwdriver
 For scraping away excess flux and dirt between tracks, as well as
driving screws.
32
Basic PCB Skills and Tools
Tools Required for Circuit Construction (Con.)
Small electric drill
 Ideally this should be mounted in a drill stand.
 We will need a range of small drill bits, but for most holes a 1mm bit is
suitable. Larger holes can be drilled with a hand drill but 1mm bits are too
fragile to use reliably in a hand drill.
33
Basic PCB Skills and Tools
Soldering Guide: HOW TO SOLDER
A few safety precautions:
 Never touch the element or tip of the soldering iron.
• They are very hot (about 400°C) and will give you a nasty burn.
• Take great care to avoid touching the mains flex with the tip of the iron.
• The iron should have a heatproof flex for extra protection. An ordinary
plastic flex will melt immediately if touched by a hot iron and there is a
serious risk of burns and electric shock.
 Always return the soldering iron to its stand when not in use.
• Never put it down on your workbench, even for a moment!
 Work in a well-ventilated area.
• The smoke formed as you melt solder is mostly from the flux and quite
irritating. Avoid breathing it by keeping you head to the side of, not
above, your work.
 Wash your hands after using solder.
• Solder contains lead which is a poisonous metal.
34
Basic PCB Skills and Tools
Soldering Guide: HOW TO SOLDER (Con.)
Always return the
soldering iron to its
stand when not in use.
Use a damp sponge,
frequently, to keep the
bit clean.
35
Basic PCB Skills and Tools
Soldering Guide: HOW TO SOLDER (Con.)
Tinning the bit, Heating the
joint and applying the solder.
Tin the bit for good heat
conduction.
(This
means
putting a small blob of solder
on the tip of the bit).
Hold the iron like a pen.
Rest your hands on the workbench
to make them steady.
Take precautions against the work
moving (use a small vice or sticky
tape).
Heat the biggest part of the joint
for 2-3 seconds.
36
Basic PCB Skills and Tools
Soldering Guide: HOW TO SOLDER (Con.)
PRACTICE MAKES PERFECT !!!
37
Basic PCB Skills and Tools
Important Components
38
Basic PCB Skills and Tools
Important Components (Con.)
39
Basic PCB Skills and Tools
De-soldering Components
Tools required: pliers, cutters, soldering iron, and solder sucker (desoldering tool).
Take great care to avoid damage.
Components cost a few pence, an assembled
printed circuit board may be worth several
hundred pounds.
Ensure the iron bit is well tinned. Heat
up the joint to be de-soldered until the solder
runs. Apply the solder sucker and remove the
solder. This should only take two or three
seconds.
Working on a double-sided PCB (where copper tracks are on both sides of
the PCB) is more difficult and requires more care.
It is often safer to cut the component leads and discard the component,
then desolder the leads individually.
40
41
Circuit Design Using Crocodile Technology 3D
Crocodile Technology 3D




Crocodile is a compilation of circuit design
tools and simulation tools.
This application is also good for beginners who
wanted to learn electronics.
The simulation tools help learners / users to
experiment circuit connections without being
worried about component get burns because of
wrongly connected.
You can always replace burnt component with a
new one by simply drag and drop.
42
Circuit Design Using Crocodile Technology 3D
Creating New File
1. Click File >> New
2. Click “Rectangular PCB space” from the Parts Library pane and drag it
to the scene space
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Circuit Design Using Crocodile Technology 3D
Working Space
Parts
tray
Click and drag parts to PCB space
3D / PCB space
Schematic space
Parts
tray
44
Circuit Design Using Crocodile Technology 3D
Circuit Designing Practice
Find and drag all the components below to the PCB space
No.
Component
Value
Qty
1.
Resistor
470 Ohm
3
2.
Resistor
10 kOhm
2
3.
Capacitor
100 uF
1
4.
Diode
1N914
1
5.
IC 555 timer
-
1
6.
4027 dual JK flip flop
-
1
7.
LED
-
3
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Circuit Design Using Crocodile Technology 3D
Drawing the Schematic
Draw the schematic below on the schematic space.
See the circuit simulation by clicking the switch button on
the schematic
46
Circuit Design Using Crocodile Technology 3D
Crocodile Technology to Real PCB
 Once a circuit has been designed and simulated/tested in Crocodile
Technology and any necessary alterations made, the completed circuit is
ready for export to ‘real PCB’.
 Both Crocodile Technology and Real PCB software must be running at the
same time for this to be possible.
 The conversion to PCB layout can be achieved through a menu in Crocodile
Technology. Real PCB converts the circuit diagram effortlessly to PCB layout
and usually with 100% accuracy.
47
Circuit Design Using Crocodile Technology 3D
Working with Real PCB
 Real PCB can also be used to construct a circuit as a PCB
layout, from scratch, by selecting components from a series of
menus and drawing the tracks connecting them. It can be used by
both beginners and experts to produce accurate PCBs. Quality
checks can be carried out automatically and the software will also
produce a bill for the components used on any PCB.
 The ‘Pour Copper’ menu changes the final PCB by only removing
enough copper so that the tracks can be seen. This means that only
the necessary copper is removed to ensure the final circuit works.
This extends the life of etchant used in the etchant tank.
 Two more ways of presenting the PCB. The 'artwork' layout is the
most likely to be printed out on a transparency, ready for conversion
to PCB. The ‘real life’ layout style shows the PCB with its
components. This is useful when arranging the components on the
PCB, as the position of each can be check against a real life printed.
48
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
When the PCB layout is finished it is
printed on a transparency and becomes
known as a PCB mask. The PCB mask is
transferred to the UV box, which is the next
stage in the manufacture of a printed circuit
board.
Advantages of using circuit and PCB software:
1. Circuits can be simulated on screen without the need to build a circuit on a breadboard
with real components.
2. Errors can be corrected and alterations made to the circuit by simply replacing
components from menus.
3. No soldering is needed, simply move components with a mouse.
4. Using simulation software is safer than soldering with hot soldering irons and avoids
dangerous fumes being produced whilst soldering.
5. Once a PCB has been designed it can be printed onto transparencies repeatedly, all to
the same high quality.
6. PCB layout software is more accurate than drawing a circuit by hand.
49
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
 Jumper wires exist when Real PCB finds out that
there are no possibilities of copper connection.
 But you can always eliminate jumper wires by
rearranging the components position.
 Try rearranging the components until a PCB artwork
with minimum or no jumper wires at all.
Jumper
wires
50
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
Exporting to Real PCB
51
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
• For the first time, simply click
“Quick” button.
• Take note on the “circuit
warnings” down below…
52
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
1
2
Click this button to
open Real PCB
Click this button to see error log
53
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
Jumper wire
Tools pane
54
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
55
Circuit Design Using Crocodile Technology 3D
Working with Real PCB (Con.)
 It will always be a
good practice to print
the artwork to a white
paper first.
 This will allow you to
check the arrangement
and the orientation of
the components easily.
 If you’ve satisfied with
the artwork than print it
on a transparency film
to create a PCB mask.
56
USING
EAGLE SOFTWARE
57
Circuit Design Using EAGLE Software
EAGLE Software


Eagle software is used to design schematic
diagram i.e. the circuit and then transfer it into
a PCB layout
However, Eagle does not perform
analysis like PSPICE or ORCAD.
circuit
58
Circuit Design Using EAGLE Software
Creating New Project
File >> New >> Project
59
Circuit Design Using EAGLE Software
Creating New Project (Con.)
60
Circuit Design Using EAGLE Software
Rename Project & Schematic
 Right click on the New Project folder icon to access the menu.
 Rename the project before creating a new schematic since it is not
possible to change the project’s name while it is in use.
61
Circuit Design Using EAGLE Software
LIBRARY
• Set up the library before working on the schematic .
• Right click on the Library, and choose “Use all”.
• Some user might drop components that he/she don’t want. This will
make sure that all the components library is selected
62
Circuit Design Using EAGLE Software
Designing Space
Copy
Select / Move
Add Parts – This is where all the parts needed stored in
the library
Connecting Wires
NOTE: Right hand click to rotate your parts
63
Circuit Design Using EAGLE Software
Example: Rectifier Circuit
An AC signal
produced by a
function generator

Output will be
connected to an
oscillator
Now construct the circuit using the schematic.
64
Circuit Design Using EAGLE Software
Selecting Components
This window will appear if ‘Add Part’ Icon is clicked.
Write the type of component (Ex. DIODE), Choose the model D1N4148.
65
Circuit Design Using EAGLE Software
Selecting Components
To select the part just
click OK and the part
will be displayed on
the
schematic
window.
WARNING!!! NEVER CLICK "Drop".
By clicking the "Drop" button, this part is deleted from
the list. If you’ve clicked the "Drop" button by mistake,
you can reset the library on Control Panel.
66
Circuit Design Using EAGLE Software
Selecting Components (Con.)
To position the component
simply click the left
mouse button anywhere
on the window.
Click again to get another
same component.
To stop the addition function of the component, strike
the ESC key and click "Cancel”.
OR
Press STOP in the toolbar.
67
Circuit Design Using EAGLE Software
Selecting Components (Con.)
Adjust the display screen using Fit, In and Out button.
To delete,
click delete button,
click on the parts to delete
press STOP to end this operation.
68
Circuit Design Using EAGLE Software
Wiring the parts
 After putting the component, wiring can be done by the Wire function.
 Left click the lead wire of the part and double-click at the end point
which of wiring.
 It isn't necessary to keep to push the mouse button during wiring work.
 To stop this feature, press STOP button.
The drawn line can be erased using the
Delete button.
Can also wire the components using bus icon.
69
Circuit Design Using EAGLE Software
Wiring the parts (Con.)
 A circular black mark is put to the node of the wiring. This mark isn't
related to the wiring of the printed board. It is to confirm the
connection of the wire when the person sees the schematic.
 When pushing the Junction button, the circular mark which moves with
the mouse pointer appears.
 A mark is drawn to the schematic when left clicking at the node.
 To stop this feature, it clicks the Cancel button.
70
Circuit Design Using EAGLE Software
Practice
Draw this circuit:
A 5volt voltage regulator circuit using IC 7805 .
After drawing a schematic, the mistake can
be automatically detected by the ERC
(Electrical Rule Check) button.
71
Circuit Design Using EAGLE Software
WIREPADS



We need to have PADs included in schematic so
that PCB can be connected to power supply, GND
and the output node
So, again click Add parts, search for Pad, and find
wire pads.
Use the ( 1,6 /0,8) package.
72
Circuit Design Using EAGLE Software
WIREPADS (Con.)
WIREPADS
73
Circuit Design Using EAGLE Software
Tips
Can label the wire pads by clicking the icons and then
select the items to rename or put values for the
resistors/capacitors.
Can do this in schematic diagram.
74
Circuit Design Using EAGLE Software
Related Instructions

Invoke
◦ Use when it involves ICs.
◦ It is common for an IC to
have more than 1 logic
circuit in it,
for example, an IC for
NOT gate ( 74LS04N ).
◦ There are 6 NOT
the IC. Hence,
allows you to
other
logic
accordingly.
gates in
invoke
connect
circuits
75
Circuit Design Using EAGLE Software
Electrical Rule Check (ERC)

ERC is performed to check schematic
transforming them into a PCB layout.

Once the icon is clicked, a text file will appear
producing list of errors and warnings.

Correct schematic and perform ERC again.

IT IS VERY
SCHEMATIC
IMPORTANT
TO
GET
A
before
CORRECT
Icon associated with ERC
76
Circuit Design Using EAGLE Software
Example of ERC
EAGLE Version 4.09r2 Copyright (c) 1988-2002 CadSoft
Electrical Rule Check for C:/PROGRAM FILES/EAGLE-4.09R2/projects/test/test.sch
WARNING: Sheet 1/1: POWER Pin IC1P VCC connected to +5V
Board and schematic are consistent
0 errors
1 warning
77
Circuit Design Using EAGLE Software
Starting New Project: Board File
Click "Board" icon in the schematic window.
When a board isn't made yet, board creating is confirmed by following
dialog.
78
Circuit Design Using EAGLE Software
Creating Board File
 The yellow line among the parts is the line which shows a connection
among them.
 But, these lines are not wiring for the printed board yet.
79
Circuit Design Using EAGLE Software
Creating Board File
 Need
to move your parts into the frame.
 Click on
 Select
all the parts, click on
 Right hand click the grouped parts.
 And then left hand click to place them in the frame.
 Once all parts are place in the frame, click on the
Ratsnest
icon.
Can still rotate parts even though using in the PCB layout window.
80
Circuit Design Using EAGLE Software
Parts Arrangement on the Board
 The yellow line shows a connection among the parts.
 The part should be arranged for the yellow line to be simpler.
81
Circuit Design Using EAGLE Software
What is RATNEST

A Ratsnest display:
◦ the program will draw a straight line (not a track)
between the pads of components which are connected
on the schematic.
◦ it shows the connectivity of circuit before starting
laying out tracks.
◦ At the start of board layout with all components,
placed down randomly, this will appear as a huge and
complicated random maze of lines. Hence the name
Ratsnest.
82
Circuit Design Using EAGLE Software
Placing Components

Place all the components that need to be in specific
locations.
◦ e.g. connectors, switches, LEDs

Pay attention to orientation of each part placed.

Give careful thought when placing components to minimize
trace lengths.

Put parts next to other parts they connect to.

Arrange ICs in only one or two orientations:

◦ a good job here makes routing the traces much easier.
◦ Again, the orientation of each part matters too.
◦ vertically or horizontally.
if possible, align each IC so that pin #1 is in the same place
for each part, say, on the top ( if horizontal ) and/or left
sides ( if vertical ).
83
Circuit Design Using EAGLE Software
Design Rule Check (DRC)


Firstly, set the rules for PCB layout.
Examples of what can be set with a DRC:
◦ Circuit connectivity. It checks that every track on board
matches the connectivity of schematic.
◦ Electrical clearance. Can check the clearance between tracks,
pads, and components.
◦ Manufacturing tolerances like min/max hole sizes, track
widths.

A complete DRC is performed again after finishing
PCB.
84
Circuit Design Using EAGLE Software
Design Rule Check (DRC) (Con.)
 The default is 8 mil.
 Since 1 inch is 25.4mm and 1mil is 1/1000 inches, so 8mil is about 0.2mm.
 40mil is about 1mm.
 Normally, we set it to be higher, around 16-20mil.
85
Circuit Design Using EAGLE Software
AUTOROUTE – connecting the parts
 Next,
click Autorouter icon
will appear.
and a window
Make sure your Autorouter is setup
as shown
86
Circuit Design Using EAGLE Software
Autorouting on the Board
In EAGLE, a pattern is drawn using 2 layers which are
component side and wiring side.
The blue line is the wiring on the wiring side and the red line is
wiring on the component side.
87
Circuit Design Using EAGLE Software
RIP - up




If you don’t like the design of your PCB or if there
is an error, need to re-route.
Click the RipUp icon
basically to cancelled
PCB connections.
Once clicked that, go to
and a window will
popped out.
Click Yes
Once done, rearrange the parts again, Ratsnest
and Autoroute until not satisfied with PCB design.
88
Circuit Design Using EAGLE Software
Before & After
The PCB
route is
marked in
blue
89
Circuit Design Using EAGLE Software
Customizing the Board
Since we use one sided PCB, change the red line (1top) to blue (16
bottom) without violating the board/circuit consistency. Use right click
on the red line.
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Circuit Design Using EAGLE Software
Customizing the Board (Con.)

To see exactly how the
PCB board would look
like,
click the
display icon
and
highlight
these
portions only.
91
Circuit Design Using EAGLE Software
Before & After
92
Circuit Design Using EAGLE Software
Other responsibilities
 Select the frame and move it so that it fits nicely with PCB
layout.
 Finally, print out the PCB layout on the transparency.
93
Circuit Design Using EAGLE Software
Customizing the board (Con.)
 The size of the PCB can be seen by click Info and click the frame line
(length in inch).
 If necessary adjust the size using Move to drag the frame line.
94
Circuit Design Using EAGLE Software
Printing the Layout

File >> Export
•Browse and write a filename, for example,
rectifier.
•Open using Paint and then print.
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Circuit Design Using EAGLE Software
Circuit is Framed
The white lines will be the
conducting
lines
and
nodes
You can add ‘copper
text’ by clicking the icon.
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Circuit Design Using EAGLE Software
Prototype Circuit
 555 timer IC.
 One 1N914 "switching" diode.
 Two 10 kΩ resistors.
 One 100 µF capacitor .
 4027 dual J-K flip-flop.
 Ten-segment LED.
 Three 470 Ω resistors.
 One 6 volt battery.
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Circuit Design Using EAGLE Software
Pin-diagram of 555 & JK Flip-Flop (4027)
1
8
2
7
3
6
4
5
98
Circuit Design Using EAGLE Software
Printing the Mask Pattern
 At the board, the component side pattern, the wiring side pattern, the
shape of the parts and the name of the parts are drawn together.
 When doing print in this condition, all of them have been printed. So, it is
necessary to set to print only a necessary part; the bottom copper for 1
sided PCB.
 Set at least tPlace, tDocu, tNames, tValues, tOrigin to OFF, set other
display as necessary. And set the print setting also as below.
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