What is a depletion-mode field-effect transistor (FET)?
The correct answer is A: An FET that exhibits a current flow between source and drain when no gate voltage is applied. What is a depletion-mode field-effect transistor (FET) is an FET that exhibits a current flow between source and drain when no gate voltage is applied. Depletion-mode FETs conduct with zero gate voltage. For amateur radio operators, this is important for transistor knowledge. Understanding this helps when working with FETs.
Exam Tip
Depletion-mode FET = conducts with no gate voltage. Think 'D'epletion-'M'ode = 'D'efault 'M'ode (conducts). Depletion-mode FETs conduct with zero gate voltage. Not no current (enhancement-mode), not electron mobility, not holes - just conducts with zero gate voltage.
Memory Aid
"Depletion-mode FET = conducts with no gate voltage. Think 'D'epletion-'M'ode = 'C'onducts 'D'efault. Depletion-mode FETs conduct with zero gate voltage. Important for transistor knowledge."
Real-World Application
A depletion-mode field-effect transistor: It's an FET that exhibits a current flow between source and drain when no gate voltage is applied. Depletion-mode FETs are normally on and require gate voltage to turn off. This is what it is - conducts with no gate voltage.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. No current flow when no gate voltage isn't depletion-mode - that's enhancement-mode. No current isn't depletion-mode.
Option C: Incorrect. Very high electron mobility isn't the definition - depletion-mode conducts with zero gate voltage. Electron mobility isn't the definition.
Option D: Incorrect. Holes as majority carriers isn't the definition - depletion-mode conducts with zero gate voltage. Holes isn't the definition.
题目解析
The correct answer is A: An FET that exhibits a current flow between source and drain when no gate voltage is applied. What is a depletion-mode field-effect transistor (FET) is an FET that exhibits a current flow between source and drain when no gate voltage is applied. Depletion-mode FETs conduct with zero gate voltage. For amateur radio operators, this is important for transistor knowledge. Understanding this helps when working with FETs.
考试技巧
Depletion-mode FET = conducts with no gate voltage. Think 'D'epletion-'M'ode = 'D'efault 'M'ode (conducts). Depletion-mode FETs conduct with zero gate voltage. Not no current (enhancement-mode), not electron mobility, not holes - just conducts with zero gate voltage.
记忆口诀
Depletion-mode FET = conducts with no gate voltage. Think 'D'epletion-'M'ode = 'C'onducts 'D'efault. Depletion-mode FETs conduct with zero gate voltage. Important for transistor knowledge.
实际应用示例
A depletion-mode field-effect transistor: It's an FET that exhibits a current flow between source and drain when no gate voltage is applied. Depletion-mode FETs are normally on and require gate voltage to turn off. This is what it is - conducts with no gate voltage.
错误选项分析
Option B: Incorrect. No current flow when no gate voltage isn't depletion-mode - that's enhancement-mode. No current isn't depletion-mode. Option C: Incorrect. Very high electron mobility isn't the definition - depletion-mode conducts with zero gate voltage. Electron mobility isn't the definition. Option D: Incorrect. Holes as majority carriers isn't the definition - depletion-mode conducts with zero gate voltage. Holes isn't the definition.
知识点
Depletion-mode FET, Current flow, Source and drain, No gate voltage applied
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.