A printed circuit board is used to mechanically support and electrically connect electronic components using conductive pathways (tracks).
Evolution of PCB.
Types of PCB- Single, Double Layer.
EAGLE Schematic Editor, Layout Editor, and Autorouter.
Basic terms related to Schematic, PCB Layout.
2. The name EAGLE is an acronym, which stands for:
Easily Applicable Graphical Layout Editor
3. Contents
Evolution of PCB.
Types of PCB- Single, Double Layer.
EAGLE Schematic Editor, Layout Editor, and Autorouter.
Basic terms related to Schematic, PCB Layout.
4. A printed circuit board is used to mechanically support and electrically connect
electronic components using conductive pathways (tracks).
It is also referred to as printed wiring board (PWB).
A PCB populated with electronic components is known as a printed circuit board
assembly (PCBA).
Before PCB’s came into existence, point to point construction or wire wrap were
used to construct equipments.
Introduction to PCB
Fig: Early PCB, Top with Components /
Bottom showing Copper Foil
8. A PCB can be of Single layer, Double layer or Multilayer
A Multilayer PCB has many layers- Via is used to have
interconnection between them.
A PCB is either Single Sided or Double Sided
Single Side- Populated with components on single side.
10. Pitch
Pitch of a component is the
distance between its leads.
1 mil = 1/1000 inch
1 mil = 0.001 inch
1 inch = 25.4mm
Grid of the Editor
It is recommended to
keep the grid value to
50 mil
19. Placing the footprints, which is a collection of pads that
represents how a component mounts to a PCB
After moving footprints to your
required Board size, use Ratsnest
command which calculates shortest
airwires.
Tools Ratsnest.
21. Routing the Board
Load Wire Clearance, Pad to Pad clearance and all other parameters.
Save the Design Rule for future use.
Check DRC – A message appears at the bottom left
23. Routing the Board
Auto Routing Tools Auto : for Auto Routing
Under General Tab- Select the Layers.
Example: If your PCB is a Single Layer . Top layer is used to mount the
components and bottom layer for routing, use above settings
25. Creating a New Part in Eagle Library
New Library Save.
Click on Symbol icon, Give the new symbol a
name. A warning appears, click Yes.
26. Creating a New Part in Eagle Library
Create a red box using Wire button.
Add Five pins to the box.
Name the pins according to datasheet.
Adding I/O pins
27. Creating a New Part in Eagle Library
Name and Value tags are always nice. Click on the text button and type
'>NAME' and '>VALUE‘.
>Name appears in RED but they are normally Grey in color.
Change the >NAME tag to the Name layer, and >VALUE tag to the value
layer.
Final Schematic part
28. Creating a New Part in Eagle Library
Click on Package icon and name the package.
Draw the exact Outline of your new package.
Creating Package.
29. Creating a New Part in Eagle Library
Create footprint for this device.
Click on SMD button and drop 5 Pads.
Change the dimensions of pad to match the component.
Place the Pads as per the part specification.
30. Creating a New Part in Eagle Library
FootprintPart Specification
33. Airwire:
Unrouted connection on a board, displayed in the unrouted layer.
Buried Via:
A plated through hole, which has been drilled through the current layer stack in the
production process like a normal (through) via, but does not connect all layers of the
whole board.
Core:
Two copper layers applied to a solid substrate.
Design Rule Check (DRC):
EAGLE can identify the violation of certain Design Rules (e.g. if two different tracks
overlap or are too close) with the DRC.
Device:
A fully defined element in a library. Consists of at least one Package and one Symbol.
Device Set:
Consists of Devices that use the same Symbols for the Schematic but have different
Package variant or technologies.
34. Drill:
Plated through drilling in the layout (in pads and vias)
Electrical Rule Check (ERC): EAGLE can identify the violation of certain electrical
rules (e.g. if two outputs are connected) with the ERC. It also checks the consistency of
the schematic.
Forward & Back Annotation:
Transforms all the actions one makes in a schematic online into the layout (and with
limitations from layout into schematic). Both files are consistent all the time.
Hole:
Non plated through drilling in the layout (e.g. a mounting hole).