In this tutorial, we are going to PCB Layout Placement Review Checklist.
- Basic Guideline –
- All parts are placed.
- Placement service to minimize layer count.
- Placement service to minimize board size if appropriate.
- Prefer components oriented in same direction (PIN1 always should be in same direction.
- Connector Placement Guideline –
- Connector position, orientation reviewed against mechanical drawing.
- Connector correct side of board.
- Connector pinout verified in PCB software against connector specs.
- Connector pinout and type mechanically compared with those of physically mating connectors.
- Check connector compatibility with board thickness.
- EMI requirements with power connectors taken into consideration.
- Components Placement Guideline –
- Pin out of high pin count, newly created parts verified in PCB layout software against part specs and actual part names.
- Sockets pin1 orientation is correct and proper (for ICE or ROM emulator).
- Physical dimensions of such parts verified.
- Pad location and pad stacks (solder paste, drill and keep out) of such parts verified.
- Pin assignment of FPGA verified against placed and routed FPGA design.
- Polarization label built in to silkscreen for polarized capacitors, diodes, and integrated circuits, label is visible after stuffing for ease of inspection.
- Bypass capacitors positioned well compared to the devices on the board.
- Required clearance around through hole parts area on bottom side.
- Required clearance around BGA part to allow for rework nozzle.
- Clearance between capacitors and resistors.
- Component pad to pad spacing required for rework, placement and test.
- Trace keep out built into pad stacks of non – plated through holes.
- Crystal Placement Guideline –
- Crystal and capacitors placed close to microprocessor and DSP.
- Mechanical Placement Guideline –
- Position of LED’s switches, front panel connectors reviewed against mechanical drawing of board and front panel (x, y and z dimensions)
- Board dimensions match mechanical drawing, including board thickness.
- Connector and heat sink mounting hole sizes and pad clearance verified against component and mounting hardware specifications.
- Mechanical mounting holes (like stiffener) match mechanical drawing.
- Connector and standoff location match those of mating boards.
- All heat sinks pointed in the appropriated direction for air – flow.
- No components are too small.
- Mechanical drawing reflects all mechanical parts (I/O panels, screws, tooling holes, etc.).
- Fiducially verified.
- Tooling hole size specified.
- Define hole size specified.
- Define break – ways and penalization.
- DDR2/DDR3 Placement Guideline –
- Place DDR devices with maximum distance from DSP.