Difficulty: Easy
Correct Answer: To provide an output equal to its input (no inversion) with increased drive capability
Explanation:
Introduction / Context:
Buffers are ubiquitous digital building blocks. They sit between a logic source and a load, offering higher current drive, improved fan-out, and isolation without changing logic polarity. Recognizing the buffer’s role helps with signal integrity and proper interfacing.
Given Data / Assumptions:
Concept / Approach:
A buffer outputs the same logic level it sees at its input. It neither inverts (like a NOT gate) nor necessarily “cleans up” noise in the sense of a Schmitt trigger (though some buffers include Schmitt inputs). Its key advantage is stronger output drive and isolation, maintaining logic level integrity at the load.
Step-by-Step Solution:
Input logic level is presented to the buffer.Buffer re-drives the signal with higher current capability and lower output impedance.Output logic level matches input polarity (no inversion).
Verification / Alternative check:
Examine datasheets for noninverting buffers (e.g., 74HC125/126 family) that specify higher IOH/IOL ratings than basic logic gates and no inversion symbol on the schematic.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
To provide an output equal to its input (no inversion) with increased drive capability
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