Pad Planner¶

Package name: jsl/landpatterns/pad-planner

How & Where to Place Pads

When building complex landpatterns, we are often faced with cases where the package for a particular component does something out of the ordinary. You will often run into this when looking at BGA packages where some subset of the balls in a grid may be depopulated. Sometimes this is pretty straight forward like for a thermally enhanced BGA pattern:

TODO - Figure here showing a thermally enhanced BGA

Other times, it can be more off the beaten path:

TODO - Figure here showing the Dialog chip with offset sub-grid of balls.

Regardless, we need tools to instructs the JITX environment how to place the pads we need for a particular component. This is where the "Pad Planner" comes in.

Pad Planner is a piece of code that tells the land pattern generator:

Whether or not to place a pad at a particular location.
The features of the pad to place at a particular location.

In order for the Pad Planner to provide good guidance, we have to have a common understanding between the generator and the planner:

The pads for a landpattern are generally going to be in a grid of some sort.
BGA packages have an obvious 2D grid.
Quad Packages (QFP, QFN, etc) also have a 2D grid but it isn't quite as obvious.
The Pad Planner makes the assumption that the pads of a component are arranged in a 2D grid with rows and columns.
A common shape characteristic
Many landpatterns use Rectangle for the shape of their pads.
Sometimes we might want to use RoundedRectangle or Capsule.
The Pad Planner makes the assumption that each pad's geometry will be described by a Dims object. This means that if we want to provide different shapes, we have to shim them into accepting a Dims object.
Shape Orientation - The Pad Planner doesn't actually care about this but the shapes generated by it need to align with the package's needs. The Pad Planner shapes will be aligned with the Dims object. The Package's land pattern generator is responsible for making sure that the x dimension of the shape corresponds with the lead-length direction, and the y dimension corresponds with the lead-width direction.

Summary¶

Data Types¶

ShapePadPlanner ¶

Pad Planner that always returns a Shape Converter

Constructors¶

Function	Description
ShapePadPlanner	Constructor for `defstruct ShapePadPlanner`

Functions¶

Function	Description
RoundedRectanglePadPlanner
DShapePadPlanner

Pin1-PadPlanner ¶

Constructors¶

Function	Description
Pin1-PadPlanner	Constructor for `defstruct Pin1-PadPlanner`

NoGeneratorForActivePadError ¶

Error for MisMatched Active & Generators

Constructors¶

Function	Description
NoGeneratorForActivePadError	Constructor for `defstruct NoGeneratorForActivePadError`

Pin1-PthPadPlanner ¶

Constructors¶

Function	Description
Pin1-PthPadPlanner	Constructor for `defstruct Pin1-PthPadPlanner`

PthPadPlanner ¶

Plated Through-Hole Pad Planner

Constructors¶

Function	Description
PthPadPlanner	Constructor for `defstruct PthPadPlanner`

Corner-PadPlanner ¶

Corner Pin Pad Planner

Constructors¶

Function	Description
Corner-PadPlanner (+ 1)	Constructor for `defstruct Corner-PadPlanner`

StaggerPthPlanner ¶

Constructors¶

Function	Description
StaggerPthPlanner (+ 1)	Constructor for `defstruct StaggerPthPlanner`

StaggerPadPlanner ¶

Constructors¶

Function	Description
StaggerPadPlanner (+ 1)	Constructor for `defstruct StaggerPadPlanner`

PadPlanner ¶

Pad Planner Base Type

Multis¶

Function	Description
th-pad-generator	Through-hole Pad Generator
is-through-hole?	Is this PadPlanner configured to generate through-hole pads ?
hole-generator	Hole Shape for Pad
shape-generator	Retrieve the Shape Generator for this grid position
active?	Check if this package grid location is active.
pad-generator	Retrieve the Pad Generator for this grid position

Methods¶

Function	Description
th-pad-generator	Default Through-Hole Pad Generator
pad-generator	Default implementation for the `pad-generator`
is-through-hole?	Default Implementation
hole-generator	Default `hole-shape` - No Holes Created.

General Definitions¶

Function	Description
to-CircleOrCapsule	Shape generator for Circle/Capsule
dshape-shaper
round-rect-shaper
is-omit?
chamfered-corner-shaper	Chamfered Corner Shaper

Variable	Description
rect-shaper
RectanglePadPlanner
capsule-shaper
CapsulePadPlanner

Definitions¶

ShapePadPlanner¶

Pad Planner that always returns a Shape Converter

public defstruct ShapePadPlanner <: PadPlanner :
    shaper: (Dims) -> Shape

shaper: (Dims) -> Shape

This is a default implementation of the PadPlanner interface for swapping a particular shape for all pads in a landpattern.

This is useful for when you don't want to use Rectangle (the typical default) and you want to replace it with say RoundedRectangle.

Constructors¶

ShapePadPlanner¶

Constructor for defstruct ShapePadPlanner

public defn ShapePadPlanner (shaper:(Dims) -> Shape)

Functions¶

RoundedRectanglePadPlanner¶

public defn RoundedRectanglePadPlanner (radius:Double) -> ShapePadPlanner

Returns ShapePadPlanner

DShapePadPlanner¶

public defn DShapePadPlanner (radius:Double) -> ShapePadPlanner

Returns ShapePadPlanner

Pin1-PadPlanner¶

public defstruct Pin1-PadPlanner <: PadPlanner :
    pin1-shaper: (Dims) -> Shape
    shaper: (Dims) -> Shape

pin1-shaper: (Dims) -> Shape
shaper: (Dims) -> Shape

Constructors¶

Pin1-PadPlanner¶

Constructor for defstruct Pin1-PadPlanner

public defn Pin1-PadPlanner (pin1-shaper:(Dims) -> Shape, shaper:(Dims) -> Shape)

NoGeneratorForActivePadError¶

Error for MisMatched Active & Generators

public defstruct NoGeneratorForActivePadError <: Exception :
    column: Int
    gen-func: String
    row: Int

column: Int
gen-func: String
row: Int

If the generator functions return False for an active pad grid location - then this exception will be thrown.

Constructors¶

NoGeneratorForActivePadError¶

Constructor for defstruct NoGeneratorForActivePadError

public defn NoGeneratorForActivePadError (row:Int, column:Int, gen-func:String)

Pin1-PthPadPlanner¶

public defstruct Pin1-PthPadPlanner <: PthPadPlanner :
    pin1-shaper: (Dims) -> Shape

pin1-shaper: (Dims) -> Shape - Pin 1 Pad Shaper This function is called for col=0, row=0 to construct the copper pad shape.

Constructors¶

Pin1-PthPadPlanner¶

Constructor for defstruct Pin1-PthPadPlanner

public defn Pin1-PthPadPlanner (pin1-shaper:(Dims) -> Shape, shaper:(Dims) -> Shape = ?)

PthPadPlanner¶

Plated Through-Hole Pad Planner

public defstruct PthPadPlanner <: ShapePadPlanner :

Basic Pad Planner for PTH pads. This assumes the hole size is the same for all grid locations.

Constructors¶

PthPadPlanner¶

Constructor for defstruct PthPadPlanner

public defn PthPadPlanner (shaper:(Dims) -> Shape = ?)

Corner-PadPlanner¶

Corner Pin Pad Planner

public defstruct Corner-PadPlanner <: PadPlanner :
    corner-shaper: (Dims) -> Shape
    rows: Int|Tuple<Int>
    shaper: (Dims) -> Shape

corner-shaper: (Dims) -> Shape
rows: Int|Tuple<Int>
shaper: (Dims) -> Shape

This pad planner is useful for packages like QFN, QFP, and other quad packages where the pads in the corners need to be customized to prevent overlapping pad geometry.

This pad planner accepts two shapers - one for normal pads and one for the pads in the corner. The corner pad will be used normally in the first row of a column. In the last row of a column - the corner pad will be mirrored about the X axis.

Constructors¶

Corner-PadPlanner¶

Constructor for defstruct Corner-PadPlanner

public defn Corner-PadPlanner (corner-shaper:(Dims) -> Shape, shaper:(Dims) -> Shape, rows:Int|Tuple<Int>)

Corner-PadPlanner¶

Constructor for defstruct Corner-PadPlanner

public defn Corner-PadPlanner ( -- corner-shaper:(Dims) -> Shape, shaper:(Dims) -> Shape, rows:Int|Tuple<Int>)

StaggerPthPlanner¶

public defstruct StaggerPthPlanner <: PthPadPlanner :
    phase: StaggerPhase

phase: StaggerPhase - Set the stagger phase for the planner

Constructors¶

StaggerPthPlanner¶

Constructor for defstruct StaggerPthPlanner

public defn StaggerPthPlanner (shaper:(Dims) -> Shape, phase:StaggerPhase = ?)

StaggerPthPlanner¶

Constructor for defstruct StaggerPthPlanner

public defn StaggerPthPlanner ( -- shaper:(Dims) -> Shape = ?, phase:StaggerPhase = ?)

StaggerPadPlanner¶

public defstruct StaggerPadPlanner <: ShapePadPlanner :
    omits: Tuple<[Int, Int]>
    phase: StaggerPhase

omits: Tuple<[Int, Int]> - List of [row, col] combinations that will be non-stuffed
phase: StaggerPhase - Set the stagger phase for the planner

Constructors¶

StaggerPadPlanner¶

Constructor for defstruct StaggerPadPlanner

public defn StaggerPadPlanner (shaper:(Dims) -> Shape, phase:StaggerPhase, omits:Tuple<[Int, Int]> = ?)

StaggerPadPlanner¶

Constructor for defstruct StaggerPadPlanner

public defn StaggerPadPlanner ( -- shaper:(Dims) -> Shape, phase:StaggerPhase = ?, omits:Tuple<[Int, Int]> = ?)

PadPlanner¶

Pad Planner Base Type

public deftype PadPlanner

This defines the interface for a Pad Planner. The Pad Planner is consulted by the landpattern generator when determining what pads to create and what shape those pads should have.

Multis¶

th-pad-generator¶

Through-hole Pad Generator

public defmulti th-pad-generator (x:PadPlanner, row:Int, column:Int) -> (Dims, Dims) -> Pad|False

x: PadPlanner - Pad Planner (self)
row: Int - Zero-based Index into the grid of a package's pad positions.
column: Int - Zero-based Index into the grid of a package's pad positions.
Returns (Dims, Dims) -> Pad|False - Pad Generator function with declared signature. This function will accept the following arguments:
hole:Dims - Size of the plated-through hole (not accounting for plating)
copper:Dims - Size of the pad annulus for the hole.

This function will return a pcb-pad definition which uses the shape provided by shape-generator and the hole provided by hole-generator.

This function is an alternate to the pad-generator function. This function is used to generate through-hole pads where the pad-generator is for SMT pads.

is-through-hole?¶

Is this PadPlanner configured to generate through-hole pads ?

public defmulti is-through-hole? (x:PadPlanner) -> True|False

Returns True|False

This is a flag that indicates whether this planner is intended for through-hole or surface mount pad generation. This is a helper function to make it easier to determine whether the pad-generator or th-pad-generator functions should be called in a particular application

hole-generator¶

Hole Shape for Pad

public defmulti hole-generator (x:PadPlanner, row:Int, column:Int) -> (Dims) -> Shape|False

x: PadPlanner - Pad Planner (self)
row: Int - Zero-based Index into the grid of a package's pad positions.
column: Int - Zero-based Index into the grid of a package's pad positions.
Returns (Dims) -> Shape|False - This function should return a function that will convert a Dims object into a Shape. That function will need to have the following signature:

Dims -> Shape

This function can return false for location in the grid where no hole should be created. If this function returns false at an active? = true grid location - then the related pad generation functions will raise an exception.

This function provides the user with the ability to create a plated through-hole pad instead of an SMT pad.

In general, this function should not query active? unless it needs to. The active? flag will be queried in the pad-generator functions when selecting whether to generate pad shapes.

The typical use case is to only return False if the land pattern contains zero through-hole pads. If you need to create a land pattern with a mix of through-hole and surface mount pads - it is better to construct this land pattern through composition.

If you intend to violate this convention - you must provide a reformed version of is-through-hole? in your derived implementation.

shape-generator¶

Retrieve the Shape Generator for this grid position

public defmulti shape-generator (x:PadPlanner, row:Int, column:Int) -> (Dims) -> Shape|False

x: PadPlanner - Pad Planner (self)
row: Int - Zero-based Index into the grid of a package's pad positions.
column: Int - Zero-based Index into the grid of a package's pad positions.
Returns (Dims) -> Shape|False - Shape Generator function with declared signature. This function will accept the following arguments:
Dims - Size of the generated pad

This function will return a Shape object with those properties. Note that the shape should have its own internal Pose object so that this method could add a custom offset if needed.

In general, this function should not query active? unless it needs to. The active? flag will be queried in the pad-generator functions when selecting whether to generate pad shapes.

active?¶

Check if this package grid location is active.

public defmulti active? (x:PadPlanner, row:Int, column:Int) -> True|False

x: PadPlanner - Pad Planner (self)
row: Int - Zero-based Index into the grid of a package's pad positions.
column: Int - Zero-based Index into the grid of a package's pad positions.
Returns True|False - Pad Grid location is Active.

In this context, active means that there should be a copper pad at this location. inactive means that no copper pad should be placed at this location.

pad-generator¶

Retrieve the Pad Generator for this grid position

public defmulti pad-generator (x:PadPlanner, row:Int, column:Int) -> (Dims) -> Pad|False

x: PadPlanner - Pad Planner (self)
row: Int - Zero-based Index into the grid of a package's pad positions.
column: Int - Zero-based Index into the grid of a package's pad positions.
Returns (Dims) -> Pad|False - Pad Generator function with declared signature. This function will accept the following arguments:
Dims - Size of the generated pad

This function will return a pcb-pad definition which uses the shape provided by shape-generator.

Methods¶

th-pad-generator¶

Default Through-Hole Pad Generator

defmethod th-pad-generator (x:PadPlanner, row:Int, column:Int) -> (Dims, Dims) -> Pad|False

Returns (Dims, Dims) -> Pad|False
Throws NoGeneratorForActivePadError - When an improper configuration of hole and shape generator functions are provided to an active grid location.

The default implementation will generate either plated or non-plated holes depending on whether the shape-generator returns true or false. For non-plated holes - the copper:Dims argument will be ignored.

If the user tries to use th-pad-generator when hole-generator returns false - then this function will raise an error.

pad-generator¶

Default implementation for the pad-generator

defmethod pad-generator (x:PadPlanner, row:Int, column:Int) -> (Dims) -> Pad|False

Returns (Dims) -> Pad|False

By default, this function will use the smd-pad generator for creating the pad definition. The default soldermask and pastemask settings will be used.

is-through-hole?¶

Default Implementation

defmethod is-through-hole? (x:PadPlanner) -> True|False

Returns True|False

This just checks if hole-generator returns False or not.

hole-generator¶

Default hole-shape - No Holes Created.

defmethod hole-generator (x:PadPlanner, row:Int, column:Int) -> (Dims) -> Shape|False

Returns (Dims) -> Shape|False - Always false

General Definitions¶

to-CircleOrCapsule¶

Shape generator for Circle/Capsule

public defn to-CircleOrCapsule (d:Dims) -> Shape

Returns Shape

For through-holes, the most common shapes are circles and slots. This is a helper function for creating those patterns in the PthPadPlanner

dshape-shaper¶

public defn dshape-shaper (radius:Double) -> (Dims) -> Shape

Returns (Dims) -> Shape

round-rect-shaper¶

public defn round-rect-shaper (radius:Double) -> (Dims) -> Shape

Returns (Dims) -> Shape

is-omit?¶

public defn is-omit? (omits:Tuple<[Int, Int]>, row:Int, column:Int) -> True|False

Returns True|False

chamfered-corner-shaper¶

Chamfered Corner Shaper

public defn chamfered-corner-shaper (radius:Double) -> (Dims) -> Shape

Returns (Dims) -> Shape

This function is intended to be used with Corner-PadPlanner to implement the differential corner pads.

rect-shaper¶

public val rect-shaper

RectanglePadPlanner¶

public val RectanglePadPlanner

capsule-shaper¶

public val capsule-shaper

CapsulePadPlanner¶

public val CapsulePadPlanner

Forwarded by packages: jsl/landpatterns/framework, jsl/landpatterns

Pad Planner¶

Summary¶

Data Types¶

Constructors¶

Functions¶

Constructors¶

Constructors¶

Constructors¶

Constructors¶

Constructors¶

Constructors¶

Constructors¶

Multis¶

Methods¶

General Definitions¶

Definitions¶

ShapePadPlanner¶

Constructors¶

ShapePadPlanner¶

Functions¶

RoundedRectanglePadPlanner¶

DShapePadPlanner¶

Pin1-PadPlanner¶

Constructors¶

Pin1-PadPlanner¶

NoGeneratorForActivePadError¶

Constructors¶

NoGeneratorForActivePadError¶

Pin1-PthPadPlanner¶

Constructors¶

Pin1-PthPadPlanner¶

PthPadPlanner¶

Constructors¶

PthPadPlanner¶

Corner-PadPlanner¶

Constructors¶

Corner-PadPlanner¶

Corner-PadPlanner¶

StaggerPthPlanner¶

Constructors¶

StaggerPthPlanner¶

StaggerPthPlanner¶

StaggerPadPlanner¶

Constructors¶

StaggerPadPlanner¶

StaggerPadPlanner¶

PadPlanner¶

Multis¶

th-pad-generator¶

is-through-hole?¶

hole-generator¶

shape-generator¶

active?¶

pad-generator¶

Methods¶

th-pad-generator¶

pad-generator¶

is-through-hole?¶

hole-generator¶

General Definitions¶

to-CircleOrCapsule¶

dshape-shaper¶

round-rect-shaper¶

is-omit?¶

chamfered-corner-shaper¶

rect-shaper¶

RectanglePadPlanner¶

capsule-shaper¶

CapsulePadPlanner¶

Related Packages¶