What Really Kills Electronics?

💀Electrostatic Discharge (ESD)

How it kills: High voltage ESD events can permanently damage semiconductor junctions, creating latent failures that manifest weeks or months later. Test standards like IEC 61000-4-2 specify up to 15kV air discharge for system-level immunity testing.

The stealth factor: Repeated ESD events and latent damage are well-documented; effects are device- and stress-dependent. Your circuit works perfectly after assembly, passes all tests, then mysteriously fails in the field due to accumulated ESD stress.

ESD Voltage Source	Typical Range (depends on humidity)	What's at Risk
Walking on carpet	1.5-35kV (low to high humidity)	CMOS inputs, microcontroller pins
Removing tape from roll	2-20kV	Analog front-ends, ADCs
Handling plastic materials	1-15kV	Op-amps, precision references
Human body (dry conditions)	2-8kV	Any unprotected IC pin

Ranges strongly depend on RH/materials; adapted from ESDA examples.

🌡️Thermal Stress

How it kills: Heat accelerates failure mechanisms in electronics. Many commercial parts specify Tj(max) 125–150°C; design to keep Tj comfortably below the datasheet maximum. The widely-used "10°C rule" suggests component life roughly halves for every 10°C increase, though this rule-of-thumb varies significantly by failure mechanism and is most applicable to certain chemistries like electrolytic capacitors.

The cascade effect: One overheating component increases ambient temperature, stressing nearby components, which then generate more heat, accelerating degradation.

• Electrolytic capacitor aging: ESR increases with temperature, ripple voltage rises
• Solder joint fatigue: Thermal cycling creates micro-cracks, intermittent connections
• IC parameter drift: Precision circuits lose accuracy, timing circuits drift
• PCB substrate stress: High temperatures can cause delamination and trace lifting

🔌Power Distribution Network Issues

How it kills: Each IC has specific operating voltage ranges and noise tolerance requirements. Many modern microcontrollers operate from 1.71V to 3.6V, while others have tighter specifications. Power supply noise, voltage drops, and current spikes create stress that accumulates over time.

The invisible killers:

• Ground bounce: High-speed switching creates voltage spikes and transients that can trigger latch-up in CMOS devices (see JESD78)
• Power supply droop: Insufficient decoupling causes voltage dips during current spikes
• Current density violations: Traces carrying more current than their width can handle
• Via impedance: Use multiple short vias at each decoupler; avoid sharing vias among caps

📻Electromagnetic Interference

How it kills: EMI typically causes functional upsets—logic errors, data corruption, and analog circuit instability. While EMI itself doesn't usually cause permanent damage, the transients and noise that accompany EMI can trigger latch-up conditions or electrical overstress that may permanently damage components. Fast transients (ESD/EFT/overshoot) can trigger latch-up (see TI Latch-up Guide).

The interference sources:

• Clock signal radiation: High-speed edges couple into sensitive circuits
• Ground loops: Multiple ground connections create antenna structures
• Uncontrolled impedances: Reflections and ringing stress digital inputs
• Power supply switching noise: Coupling through shared power/ground

⚙️Process-Induced Failures

How it kills: Manufacturing defects create latent failures—weak solder joints, contamination, and process damage that manifest as field failures months after production.

Manufacturing Issue	Immediate Symptom	Long-term Killer
Cold solder joints	Often none (works initially)	Intermittent connections, total failure
Flux residue	Often none visible	Corrosion, leakage currents
Via barrel cracks	Passes connectivity test	Thermal cycling causes open circuit
Component stress	Works within spec	Accelerated aging, parameter drift

💧Moisture, Corrosion, and Contamination

How they kill: Environmental factors create electrochemical reactions that slowly dissolve your circuit traces, degrade insulation, and create conductive paths where none should exist.

• Humidity absorption: PCB substrates absorb moisture, reducing insulation resistance
• Salt contamination: Creates conductive paths, accelerates corrosion
• UV degradation: Breaks down plastic components, changes electrical properties
• Chemical exposure: Cleaning solvents, flux, even skin oils cause long-term damage

🤚Assembly and Testing Damage

How it kills: Physical damage during handling, probe contact damage during testing, and mechanical stress from connectors and cables create failure sites that worsen over time.

• Test probe damage: Sharp probes scratch protective coatings, create corrosion sites
• Connector stress: Repeated insertion/removal cycles cause trace lifting
• Component handling: Static-sensitive devices damaged during manual placement
• Rework damage: Heat damage to adjacent components during repairs

⚡The Power-Ground Assassin

The Setup: A perfectly working prototype, tested and ready for production. Everything checked out—until it didn't.

The Kill: Three different ways this silent killer struck:

• Library Symbol Sabotage: An incorrect symbol in the component library had power and ground pins swapped. The schematic looked perfect, the design passed all checks, but first power-up was the last power-up.
• Manufacturing Ambush: A fabrication error created an internal short between power and ground planes. The boards looked perfect from the outside, but every single one was DOA.
• Mechanical Execution: A mounting screw abraded through the soldermask, exposing a power trace. The screw was grounded to the enclosure. One installation later: instant short, magic smoke, project delayed by 6 weeks.

The Aftermath: Complete board respin, new fab run, and a very expensive lesson about the importance of power integrity verification at every level.

🔗The Board-to-Board Connector Phantom

The Setup: Multi-board system with critical connections between PCBs. Each board worked perfectly in isolation.

The Kill: Mechanical tolerance stackup meant connectors didn't align properly. Some pins made intermittent contact, others were stressed beyond their limits. The system would work, then fail randomly, creating the worst kind of debugging nightmare.

The Silent Part: The connection looked fine—it was electrically continuous during testing. But mechanical stress on the connector pins created microscopic cracks that became full opens under thermal cycling.

The Aftermath: Three board respins to get the mechanical positioning right, plus a complete connector strategy overhaul. Lesson learned: mechanical engineers and PCB designers need to work together from day one.

💻The FPGA Voltage Assassin

The Setup: High-performance FPGA design with multiple voltage domains. Careful power sequencing, proper decoupling, everything by the book.

The Kill: A stressed I/O pin on the FPGA was supposed to see 1.8V logic levels. Due to a level shifter design error, it received 3.3V instead. The FPGA's input protection clamped the voltage—but couldn't handle the current.

The Chain Reaction: The FPGA I/O pin shorted internally, creating a direct path from 3.3V to ground. This overloaded the power supply, which tripped its protection circuit. The entire system went dark, and the $200 FPGA became a silicon paperweight.

The Aftermath: Board respin with proper level shifting, additional current limiting, and paranoid voltage domain verification. One small voltage error killed the most expensive component on the board.

🔋The Power Supply Strangler

The Setup: Custom switching power supply design, calculated for efficiency and cost optimization. Breadboard prototype worked perfectly.

The Kill: Two silent killers worked in concert:

• Design Oversight: The feedback compensation network was miscalculated, causing the power supply to oscillate instead of starting properly.
• Programming Error: A programmable power management IC had incorrect startup sequence parameters, preventing the enable signals from reaching the switching controller.

The Silent Part: The power supply would attempt to start, fail, retry, fail again—all silently. No error indicators, no debug outputs, just a dead system that looked like it should work.

The Aftermath: Complete power supply redesign and a new rule: always include diagnostic LEDs and test points for every critical power management function.

🧠The Memory Corruption Phantom

The Setup: High-speed DDR memory interface, carefully routed with controlled impedance and proper termination. Timing simulation showed everything was within spec.

The Kill: Signal integrity issues caused random bit errors in memory transactions. The symptoms were subtle—occasional data corruption, rare system crashes, intermittent failures that seemed unrelated to memory.

The Silent Attack: The signal integrity problems were marginal—not bad enough to prevent the system from working, but bad enough to cause rare errors. These errors accumulated over time, corrupting data and making the system unreliable.

The Investigation: Weeks of debugging led to the discovery that via stubs on the memory traces were causing reflections. The reflections didn't prevent data transmission but occasionally corrupted it. Via-stub reflections → back-drilling/back-drill rule-checks (see Signal Integrity Journal).

The Aftermath: Board respin with back-drilling to remove via stubs, improved trace routing, and comprehensive signal integrity verification. A seemingly minor SI issue nearly killed the entire project.