Pull-up and pull-down resistors — purpose check: Engineers use pull-ups to hold a floating input HIGH and pull-downs to hold a floating input LOW. Assess the statement: “Pull-up resistors and pull-down resistors are used to keep a floating terminal HIGH.”

Introduction / Context:
Reliable logic requires defined input levels. Floating inputs can drift, oscillate, or pick up noise. Pull-up and pull-down resistors provide a default logic level when no active driver is present, preventing undefined behavior and excess power consumption.

Given Data / Assumptions:

• “Floating” means high-impedance, no strong driver.
• Pull-up connects the node to VCC through a resistor.
• Pull-down connects the node to GND through a resistor.
• Active drivers can override the weak pull.

Concept / Approach:
A pull-up biases a node HIGH; a pull-down biases it LOW. The statement claims both are used to keep a floating terminal HIGH, which is incorrect since pull-downs explicitly bias LOW. Correct usage depends on the logic polarity and desired idle state (e.g., active-low inputs typically use pull-ups).

Step-by-Step Solution:
Identify desired default: HIGH → use pull-up; LOW → use pull-down.Confirm the statement lumps both as keeping HIGH → incorrect.Note special cases (open-drain/open-collector) still use pull-ups for HIGH; pull-downs are not for HIGH.Therefore, the claim is false.

Verification / Alternative check:
MCU application notes illustrate input mode with pull-ups for buttons to ground (idle HIGH) and pull-downs for buttons to VCC (idle LOW).

Why Other Options Are Wrong:
“Correct” contradicts definitions. Open-drain outputs indeed require pull-ups for HIGH, but that does not make pull-downs a means to hold HIGH. Schmitt triggers improve noise margins but do not change pull-down polarity.

Common Pitfalls:
Leaving CMOS inputs floating; choosing pull values too strong (wasting power) or too weak (slow edges, noise-susceptible).

Final Answer:
Incorrect