PCB failure can occur for several reasons, with the end result being that the PCB no longer functions properly. Since PCBs are used in many electronics, such as wearables, airplanes, satellites and medical devices, it’s crucial that any failures are identified quickly and the appropriate action is taken. Any company looking to keep their electronics running smoothly can better address PCB failure and even prevent it from occurring by knowing more about why it happens.
1. Soldering Issues
- Cold Solder Joints: Occurs when the solder does not properly melt, leading to weak electrical connections. They often appear dull or grainy.
- Solder Bridges: Excess solder can create unintended connections between adjacent pads or traces, causing shorts
- Insufficient Solder: Too little solder can result in weak joints, leading to intermittent connections or complete failure.
2. Component Placement Issues:
- Misaligned Components: If components are not properly aligned on the PCB, it can lead to poor connections or mechanical stress.
- Tombstoning: One end of a surface-mounted component lifts off the PCB during soldering, leading to a lack of electrical connection.
- Incorrect Orientation: Polarized components (like diodes or capacitors) placed backward can cause the circuit to malfunction or damage the component.
3. Electrical Shorts
- Trace Shorts: Caused by design errors or accidental contact during assembly, resulting in unintended connections between traces.
- Component Shorts: Faulty components or manufacturing defects can cause internal shorts, leading to circuit failure.
4. Open Circuits
- Broken Traces: Physical damage, poor manufacturing, or corrosion can break the conductive traces, interrupting the circuit.
- Loose Connections: Connectors or solder joints that are not properly secured can lead to intermittent or complete disconnections.
5. Thermal Issues
- Overheating Components: Components that generate excessive heat can damage the PCB or other nearby components, leading to failure.
- Thermal Cycling: Repeated heating and cooling can cause solder joints to crack or components to shift, resulting in failures over time.
- Inadequate Heat Dissipation: Poor PCB design can lead to insufficient heat management, causing components to overheat.
6. Contamination
- Flux Residue: If not properly cleaned, flux can cause corrosion or conductive paths that lead to shorts or intermittent connections.
- Dust and Debris: Particles can accumulate on the PCB, leading to shorts or interference with signal paths.
- Moisture Absorption: PCBs exposed to humid environments can absorb moisture, leading to corrosion, swelling, or short circuits.
7. Design Flaws
- Inadequate Trace Width: Traces that are too narrow can overheat or break under high current loads.
- Poor Grounding: Improper grounding can cause noise issues, signal integrity problems, or even damage components.
- Incorrect Component Rating: Using components with incorrect voltage, current, or temperature ratings can lead to premature failure.
8. Environmental Factors
- Corrosion: Exposure to harsh environments can cause oxidation or corrosion of metal parts, leading to open circuits or shorts.
- Vibration and Mechanical Stress: Physical stress from vibration or impact can cause solder joints to crack or components to detach.
- Electromagnetic Interference (EMI): Poor shielding or design can result in EMI, causing noise or malfunctions in sensitive circuits.
9. Manufacturing Defects
- Delamination: Layers of the PCB can separate due to poor manufacturing processes or thermal stress, leading to open circuits.
- Via Failures: Vias (plated holes connecting different layers of the PCB) can fail due to poor plating or thermal stress, interrupting connections between layers.
10. Aging and Wear
- Material Degradation: Over time, materials used in PCBs (like the substrate or copper traces) can degrade, leading to failures.
- Component Wear: Components can wear out over time, especially capacitors, which can lose capacitance or short out as they age.
Preventive Measures and Best Practices
Fortunately, most of these errors can be avoided with knowledge and consideration for the manufacturing process, as well as awareness of the more common PCB manufacturing issues. Following a set of standard design rules and considerations can aid in preventing component failure, connection issues and other circuit board problems.
Reach out to Epsilon Electronics for PCB Design, PCB Fabrication, BOM Procurement, Hardware Manufacturing, PCB Assembly. Our expert team can help you to launch your product on time with all quality aspect consideration at every stage.
Contact Details:
Call Us: +91 9879 6261 81
Email: pcb@epsilonelectronics.in
Web: www.mfg.epsilonelectronics.in
