EAGLE Style Guide

Part Creation

Symbol

Grid

• Size: 0.1 in
• Alt: 0.01 in

Name

• Should be manufacturer part/family number (eg. ATTINY167-SU)

Description

• Leave blank

Style

• Origin
  • Center origin (crosshair) on symbol center
• Text
  • Keep text horizontal
  • Size: 0.07 in
  • Ratio: 8%
  • Line Distance: 50%
  • Font: proportional
• Name
  • Locate in top left of symbol
  • Align: bottom-left
  • Layer: 95 Names
  • Value: >NAME
• Value
  • Locate in bottom-left of symbol
  • Align: top-left
  • Layer: 96 Values
  • Value: >VALUE
• Outline
  • Use Lines
    • Width: 0.01 in
    • Style: continuous
    • Layer: 94 Symbol
    • Curve: 0
  • Try to have a length/width that is a 0.1 in multiple (eg. 0.4 in by 0.4 in)

Functionality

• Pins
  • Label pins to allow the symbol to be applied to parts in similar families
  • Name: Based on part datasheet
  • Direction: pas (passive)
  • Swap Level: 0
  • Length: middle
  • Function: none
  • Visible: both
• Pin Placement
  • Power (VCC): top left
  • Ground (GND): bottom right
  • Inputs: left edge
  • Outputs: right edge
• Passive Pins
  • Specifically resistors, capacitors, inductors, fuses, diodes
  • Visible: off
• Connector Pins
  • Try to reuse an existing symbol for the size of connector
  • If need to make a new one, for pins:
    • Visible: pad
• Decimal Labeling
  • For fractional values include the decimal point (eg. 3.3V, 4.5K)

Footprint

Grid

• Size: 1 mm
• Alt: 0.1 mm

Name

• Should be manufacturer footprint name (eg. SOIC-20)

Description

• Link to datasheet for part/family for pad layout

Style

• Origin
  • Center origin (crosshair) on footprint center
• Text
  • Keep text horizontal
  • Size: 1 mm
  • Ratio: 8%
  • Line Distance: 50%
  • Font: vector
• Name
  • Locate in top left of footprint
  • Align: bottom-left
  • Layer: 25 tNames
  • Value: >NAME
• Value
  • Locate in bottom-left of symbol
  • Align: top-left
  • Layer: 26 tValues
  • Value: >VALUE
• Outline
  • Use Lines
    • Width: 0.2 mm
    • Style: continuous
    • Layer: 21 tPlace
  • Draw package outline per part/family datasheet
  • Used for part placement
• Keepout
  • Use Rectangles
    • Layer: 39 tKeepout
  • Size 0.1 mm larger than the package
  • Used to prevent overlapping parts
• Details
  • Capture more part details, extensions beyond outline, etc
  • Use
    • Width: 0.2 mm
    • Style: continuous
    • Layer: 51 tDocu

Functionality

• Pad (Through-hole)
  • Name: name based on datasheet pin number
  • Diameter: auto
  • Drill: size based on datasheet
  • Shape: circle
  • Locked: unchecked
  • Thermals: checked
  • Stop: checked
  • First: unchecked
• Smd (Surface Mount)
  • Name: name based on datasheet pin number
  • Smd Size: size based on datasheet
  • Layer: 1 Top (usually)
  • Roundness: 0%
  • Locked: unchecked
  • Thermals: checked
  • Stop: checked
  • Cream: checked
• Polarity Indication
  • Through-hole
    • Make pin 1 visually different
    • Shape: square
  • Indicate polarity, when necessary
    • Prevents backwards installation
    • Direction or cathode indicators for diodes
    • Stripe or plus-minus for capacitors
  • Indicate Pin 1 for ICs
    • Use a circle (dot)
      • Width: 0 mm
      • Layer: 21 tPlace
      • Radius: 0.2 mm (at minimum)
  • Avoid overlapping pads with silkscreen, cut a section out

Device

Name

• Should be manufacturer part number (eg. ATTINY167-SU)
• Wildcards
  • Allows devices with multiple technologies (specifications) or packages
    • Uses wildcards in device name
    • Technology Name: *
    • Package Name: ?
  • Example
    • Regulator with two voltage (3.3V and 1.8V) technologies
      • AP2138N-3.3TRG1 for 3.3V
      • AP2138N-1.8TRG1 for 1.8V
      • Becomes AP2138N-*TRG1 with technology 3.3 and 1.8

Description

• One sentence part function overview (valid for all variants)
• Datasheet link

Value

• Off unless its a passive part (resistors, capacitors, inductors, fuses, diodes)
• If its a specific passive part with a value, add an attribute
  • Name: VALUE
  • Value: the value
  • Type: variable

Symbol

• Use specific symbol for that part/family
• Connectors are an exception
  • Generic symbol used for all connectors of a certain size

Footprint

• Use specific footprint if unique
• Try to reuse a footprint if it matches

Attribute (non-Passives)

• Part number
  • Name: DKPN
  • Value: the Digi-Key Part Number (eg. ATTINY167-SU-ND)
  • Type: variable

Attribute (Passives)

• Part number
  • Name: DKPN
  • Value: blank unless specific to part
  • Type: variable
• Resistors
  • Should have tolerance and power ratings that is blank by default
  • Value is for resistance only
  • Tolerance
    • Name: Tolerance
    • Value: blank unless specific to part
    • Type: variable
  • Power
    • Name: Power
    • Value: blank unless specific to part
    • Type: variable
• Capacitors
  • Should have tolerance and voltage ratings that is blank by default
  • Value is for capacitance only
  • Tolerance
    • Name: Tolerance
    • Value: blank unless specific to part
    • Type: variable
  • Voltage
    • Name: Voltage
    • Value: blank unless specific to part
    • Type: variable
• Inductors
  • Should have tolerance and current ratings that is blank by default
  • Value is for inductance only
  • Tolerance
    • Name: Tolerance
    • Value: blank unless specific to part
    • Type: variable
  • Current
    • Name: Current
    • Value: blank unless specific to part
    • Type: variable
• Fuses
  • Value is for current rating
• Diodes
  • LEDs
    • Value should be color
  • Normal Diode
    • Value should be reverse voltage
  • TVS Diode
    • Value should be [Working Voltage]-[Breakdown Voltage] (e.g. 8V-8.5V)

Prefix

Chart for Designation

Letter	Part Type
A	Separate Assembly or Subassembly
C	Capacitor
D	Diode or LED
F	Fuse
FB	Ferrite bead
J	Jack or Connector (least moveable connection part)
JP	Jumper
K	Relay or Contactor
L	Inductor
LS/BZ	Loudspeaker or Buzzer
M	Motor
P	Plug (most moveable connection part)
PS	Power Supply
Q	Transistor
R	Resistor
RN	Resistor Network
S/SW	Switch
T	Transformer
TP	Test Point
U	Integrated Circuit
X	Crystal
XF	External Fuse