Troubleshooting digital ICs: After identifying that one internal gate of an integrated circuit is faulty, what is the appropriate corrective action in standard repair practice?

Introduction / Context:
Digital integrated circuits encapsulate many gates and support structures on a single die. When one gate fails, it typically indicates irreversible internal damage. Field repair focuses on board-level replacement rather than die-level rework.

Given Data / Assumptions:

• Confirmed diagnosis: a specific gate inside an IC is nonfunctional.
• Through-hole or SMD package on a PCB.
• No specialized chip-level re-fabrication capability on site.

Concept / Approach:
ICs are monolithic; you cannot “repair” an individual gate. Best practice is to replace the entire device, ensuring pin-compatible, same or higher speed grade, and same logic family. Before replacement, you may verify power rails and clock/reset just to avoid replacing a good part due to external faults, but the corrective action remains IC replacement.

Step-by-Step Solution:
Confirm fault with logic probe/scope and substitution if available.Power down and follow ESD precautions.Desolder and remove the defective IC; clean pads/vias.Install a known-good replacement; test operation.

Verification / Alternative check:
After replacement, verify functionality at the gate’s inputs/outputs; confirm no downstream shorts or upstream drive issues remain.

Why Other Options Are Wrong:
“Repair the gate” is not feasible in monolithic ICs.

Resoldering tracks does not fix an internal die failure.

Rechecking power is good diagnostics but not the corrective action once the gate is confirmed bad.

Removing only certain pins is impractical and destructive.

Common Pitfalls:
Overlooking root causes such as overvoltage or ESD; always address the stressor to prevent repeat failures.

Final Answer:
replace the IC involved