Difference between revisions of "EAGLE Style Guide"
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===General Practices=== | ===General Practices=== | ||
===Traces=== | ===Traces=== | ||
+ | *In general | ||
+ | **'''Style:''' continuous | ||
+ | **'''Cap:''' round | ||
+ | **'''Curve:''' 0 | ||
+ | *Signals | ||
+ | **'''Width:''' 0.3mm | ||
+ | *Power | ||
+ | **'''Width:''' 0.5mm (increase as necessary for [https://www.4pcb.com/trace-width-calculator.html current requirement]) | ||
+ | *Avoid minimum sizing (based on the DRC) when possible | ||
===Via=== | ===Via=== | ||
+ | *At minimum | ||
+ | **'''Diameter:''' 0.65mm | ||
+ | **'''Drill:''' 0.35mm | ||
+ | **'''Shape:''' round | ||
+ | **'''Layer:''' 1-16 | ||
+ | *Avoid minimum sizing (based on the DRC) when possible | ||
+ | *Avoid vias on signals above 1GHz | ||
+ | *Use the same number of vias on differentially routed traces | ||
==Silkscreen== | ==Silkscreen== | ||
*Far more important than most people realize and can take a significant amount of time to get right. | *Far more important than most people realize and can take a significant amount of time to get right. | ||
Line 326: | Line 343: | ||
**Will be in final board output | **Will be in final board output | ||
**Use Lines | **Use Lines | ||
− | ***Width: 0.2 mm | + | ***'''Width:''' 0.2 mm |
− | ***Style: continuous | + | ***'''Style:''' continuous |
− | ***Layer: 21 tPlace / 22 bPlace | + | ***'''Layer:''' 21 tPlace / 22 bPlace |
*Extra Details | *Extra Details | ||
**Will not be in final board output | **Will not be in final board output |
Revision as of 00:28, 11 July 2020
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)
- Use Lines
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
- Use Lines
- Keepout
- Use Rectangles
- Layer: 39 tKeepout
- Size 0.1 mm larger than the package
- Used to prevent overlapping parts
- Use Rectangles
- 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)
- Use a circle (dot)
- Avoid overlapping pads with silkscreen, cut a section out
- Through-hole
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
- Regulator with two voltage (3.3V and 1.8V) technologies
- Allows devices with multiple technologies (specifications) or packages
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)
- LEDs
Prefix
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 |
Schematics
Grid
Sheets
Overall
Frames
Description
Nets
Style
Signals
Power
Busses
Notes
Computed Values
Specific Parts
Boards
Grid
Board Fab
Placement
General
Mechanical Considerations
Routing
General Practices
Traces
- In general
- Style: continuous
- Cap: round
- Curve: 0
- Signals
- Width: 0.3mm
- Power
- Width: 0.5mm (increase as necessary for current requirement)
- Avoid minimum sizing (based on the DRC) when possible
Via
- At minimum
- Diameter: 0.65mm
- Drill: 0.35mm
- Shape: round
- Layer: 1-16
- Avoid minimum sizing (based on the DRC) when possible
- Avoid vias on signals above 1GHz
- Use the same number of vias on differentially routed traces
Silkscreen
- Far more important than most people realize and can take a significant amount of time to get right.
- Makes a board easier to use, easier to debug, and harder to break.
Style
- Text
- Size: 1 mm (at minimum)
- Ratio: 8% (Important text can be bolded using 15%)
- Line Distance: 50%
- Font: vector
- Layer: 21 tPlace / 22 bPlace
- Markings (anything not already in footprints)
- Will be in final board output
- Use Lines
- Width: 0.2 mm
- Style: continuous
- Layer: 21 tPlace / 22 bPlace
- Extra Details
- Will not be in final board output
- Capture more details, extensions beyond outline, etc
- Use Lines
- Width: 0.2 mm
- Style: continuous
- Layer: 51 tDocu / 52 bDocu
- Measurements
- Will not be in final board output
- Useful to mark critical distances
- Can mark outer board dimensions
- Use Dimension
- Size: 2 mm
- Ratio: 8% (Important dimensions can be bolded using 15%)
- Layer: 47 Measures
- DType: parallel
- Line Width: 0.2mm
- Ext. Line Width:v auto
- Ext. Line Length: auto
- Ext. Line Offset: auto
- Unit: mm
- Precision: 3
- Show unit: checked
Labels
- Label all power inputs with name and voltage (current optional)
- Label all connectors with name
- Label all switches with position values (e.g. on or off)
- Label all debug LEDs (e.g. MCU Status)
- Label all fuses with current rating
General
- Aesthetics
- Don’t place silkscreen on vias (even tented vias) unless absolutely unavoidable
- Have your team logo on the board (e.g. RoboBuzz)
- Versioning
- Have a "vMAJOR.minor" version text label on the board (e.g. v2.1)
- Have your team name and year on the board (e.g. RoboCup 2020)
- Board ID
- White square to allow for a board ID (e.g. written 2 means board 2)
- Recommended if more than three boards will be fabricated
- Use Rectangle
- Make width and height 5mm by 5mm (minimum)
- Layer: 21 tPlace / 22 bPlace