# /manufacturing/pick-and-place

Pick and place files for automated PCB assembly.

## Purpose
This directory contains pick and place files that specify the exact position, rotation, and side of each component for automated assembly machines. These files are essential for SMT (Surface Mount Technology) assembly.

## File Types
- **`.csv`**: Component placement data (most common)
- **`.txt`**: Alternative text format
- **`.pos`**: Position file format
- **`.cpl`**: Component placement list

## Standard Pick and Place Files
```
pick-and-place/
├── ProjectName-all-pos.csv      # All components (top + bottom)
├── ProjectName-top-pos.csv      # Top side components only
├── ProjectName-bottom-pos.csv   # Bottom side components only
├── ProjectName-centroid.csv     # Component centroids
└── assembly-notes.txt           # Special assembly instructions
```

## Generating Pick and Place Files from KiCad
1. Open PCB (`.kicad_pcb`)
2. **File → Fabrication Outputs → Component Placement (.pos)**
3. Configure settings:
   - **Output directory**: `manufacturing/pick-and-place/`
   - **File format**: CSV
   - **Units**: Millimeters
   - **Files**: Separate files for top and bottom
   - **Include**: Only SMD components (exclude through-hole)
4. Generate files

## File Format and Contents
### Standard CSV Format
```csv
Ref,Val,Package,PosX,PosY,Rot,Side
C1,100nF,C_0603_1608Metric,25.4,15.24,0,top
R1,10k,R_0603_1608Metric,30.48,15.24,90,top
U1,STM32F401,LQFP-64_10x10mm_P0.5mm,50.8,25.4,0,top
```

### Column Descriptions
- **Ref**: Component reference designator (C1, R1, U1, etc.)
- **Val**: Component value (100nF, 10k, STM32F401, etc.)
- **Package**: Footprint/package name
- **PosX/PosY**: X,Y coordinates in mm (board origin)
- **Rot**: Rotation angle in degrees (0-360)
- **Side**: Component side (top/bottom)

## Coordinate System
- **Origin**: Typically bottom-left corner of PCB
- **Units**: Millimeters (preferred) or inches
- **X-axis**: Left to right (positive direction)
- **Y-axis**: Bottom to top (positive direction)
- **Rotation**: 0° = component oriented as designed

## Component Rotation Standards
### Standard Orientations
- **0°**: Component as placed in footprint
- **90°**: Rotated 90° counterclockwise
- **180°**: Rotated 180°
- **270°**: Rotated 270° counterclockwise (or -90°)

### Common Component Orientations
- **Resistors/Capacitors**: Usually 0° or 90°
- **ICs**: Pin 1 indicator position matters
- **Connectors**: Orientation critical for mating
- **Polarized components**: Polarity marking alignment

## Assembly Machine Requirements
Different assembly machines may require:
- **Coordinate format**: Decimal places and units
- **Rotation format**: 0-360° vs ±180°
- **Origin location**: Corner vs center of board
- **File format**: CSV, text, or proprietary formats
- **Component data**: Additional fields like height, type

## Quality Control Checklist
- [ ] All SMD components included
- [ ] Through-hole components excluded (unless specified)
- [ ] Coordinates within board boundaries
- [ ] Rotation values reasonable (0-360°)
- [ ] Component values match BOM
- [ ] Package names match footprints
- [ ] Top/bottom side assignment correct
- [ ] No duplicate reference designators

## Assembly Notes
Document special requirements:
- **Component orientation**: Critical alignments
- **Assembly sequence**: Order of placement
- **Special handling**: ESD sensitive components
- **Rework access**: Components that may need replacement
- **Test points**: Accessible after assembly
- **Fiducials**: Reference points for machine alignment

## Fiducial Markers
Include fiducial information for machine alignment:
- **Global fiducials**: Board-level alignment (minimum 3)
- **Local fiducials**: Fine-pitch component alignment
- **Fiducial coordinates**: Precise X,Y positions
- **Fiducial size**: Typically 1mm diameter

## Integration with Other Files
Pick and place files work with:
- **BOM**: Component specifications and quantities
- **Gerbers**: PCB layer information
- **Assembly drawings**: Visual component placement
- **Paste stencil**: Solder paste application

## Manufacturer Communication
Provide to your assembly house:
- Pick and place files
- Component orientation requirements
- Special assembly instructions
- Acceptable component substitutions
- Quality requirements and testing