Difficulty: Easy
Correct Answer: the n-type material, which is called the cathode
Explanation:
Introduction / Context:
Correctly identifying diode terminals from the schematic is critical when orienting the device on a PCB. The cathode end must align with the symbol's bar to guarantee forward conduction in the intended direction and proper rectifier behavior.
Given Data / Assumptions:
Concept / Approach:
The conventional diode symbol shows a triangle/arrow-like point directed toward a vertical bar. The bar denotes the cathode (n-type side). Thus, the pointed tip indicates the direction toward the cathode. Remember ”point to bar = cathode,” and ”current flows from anode (no bar) to cathode (bar)” when forward-biased.
Step-by-Step Solution:
Verification / Alternative check:
Use a DMM diode test: positive probe to anode and negative to cathode yields a forward drop reading (for silicon, about 0.6–0.7 V). Reversing the probes yields open circuit, matching the symbol orientation rule.
Why Other Options Are Wrong:
Common Pitfalls:
Mixing up electron flow with conventional current or confusing LED light arrows (which depict emitted light) with the diode polarity indicator.
Final Answer:
the n-type material, which is called the cathode
Discussion & Comments