What is the function of hysteresis in a comparator?
The correct answer is A: To prevent input noise from causing unstable output signals. What is the function of hysteresis in a comparator is to prevent input noise from causing unstable output signals. Hysteresis prevents oscillation from noise. For amateur radio operators, this is important for digital circuits. Understanding this helps when using comparators.
Exam Tip
Hysteresis in comparator = prevent input noise from causing unstable output. Think 'H'ysteresis = 'H'elps 'S'tability (prevents noise). Hysteresis prevents oscillation from noise. Not AC input, not continual change, not increase sensitivity - just prevent noise instability.
Memory Aid
"Hysteresis in comparator = prevent input noise from causing unstable output. Think 'H'ysteresis = 'N'oise 'P'revention. Hysteresis prevents oscillation from noise. Important for digital circuits."
Real-World Application
Hysteresis in a comparator: Its function is to prevent input noise from causing unstable output signals. Without hysteresis, noise near the threshold can cause the output to oscillate. Hysteresis creates a dead band that prevents this. This is the function - prevent noise instability.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. Allow comparator to be used with AC input signals isn't the function - hysteresis prevents noise from causing instability. AC input isn't the function.
Option C: Incorrect. Cause output to continually change states isn't the function - hysteresis prevents instability, not causes it. Continual change isn't the function.
Option D: Incorrect. Increase sensitivity isn't the function - hysteresis actually reduces sensitivity to prevent noise. Increase sensitivity isn't the function.
题目解析
The correct answer is A: To prevent input noise from causing unstable output signals. What is the function of hysteresis in a comparator is to prevent input noise from causing unstable output signals. Hysteresis prevents oscillation from noise. For amateur radio operators, this is important for digital circuits. Understanding this helps when using comparators.
考试技巧
Hysteresis in comparator = prevent input noise from causing unstable output. Think 'H'ysteresis = 'H'elps 'S'tability (prevents noise). Hysteresis prevents oscillation from noise. Not AC input, not continual change, not increase sensitivity - just prevent noise instability.
记忆口诀
Hysteresis in comparator = prevent input noise from causing unstable output. Think 'H'ysteresis = 'N'oise 'P'revention. Hysteresis prevents oscillation from noise. Important for digital circuits.
实际应用示例
Hysteresis in a comparator: Its function is to prevent input noise from causing unstable output signals. Without hysteresis, noise near the threshold can cause the output to oscillate. Hysteresis creates a dead band that prevents this. This is the function - prevent noise instability.
错误选项分析
Option B: Incorrect. Allow comparator to be used with AC input signals isn't the function - hysteresis prevents noise from causing instability. AC input isn't the function. Option C: Incorrect. Cause output to continually change states isn't the function - hysteresis prevents instability, not causes it. Continual change isn't the function. Option D: Incorrect. Increase sensitivity isn't the function - hysteresis actually reduces sensitivity to prevent noise. Increase sensitivity isn't the function.
知识点
Hysteresis, Comparator, Prevent input noise, Unstable output signals
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.