Best tools for locating shorts in digital circuits Select the instrument pair that technicians commonly use to inject a stimulus and trace abnormal current flow to locate shorted nodes on a digital board.

Introduction / Context:
Finding shorts on a dense digital PCB can be challenging. Rather than guessing, technicians use targeted tools to excite the circuit and observe where current actually flows. The right combination makes it quicker to track the fault to a specific trace or component.

Given Data / Assumptions:

• We need to detect unintended low-resistance paths that draw current.
• A safe stimulus must be applied without damaging logic devices.
• A sensitive probe should indicate where the current is traveling along copper traces.

Concept / Approach:
A logic pulser momentarily drives a pin or net with controlled pulses at logic levels. A current tracer (a handheld probe with a magnetic or resistive sensor) detects the resulting pulse current through traces, allowing you to follow it physically across the board. When a short exists, the current concentrates near the fault, producing a stronger indication and guiding you to the exact location.

Step-by-Step Solution:

Verification / Alternative check:
Technicians corroborate by lifting components or cutting jumpers near the indicated spot; continuity tests (DMM) confirm the short after the board cools and the stimulus is removed.

Why Other Options Are Wrong:

Common Pitfalls:
Overdriving the node with an improper pulser setting; misinterpreting inductive pickup from adjacent power rails as the short path; forgetting to disconnect heavy loads that mask the short’s signature.

Final Answer:
current tracer, logic pulser