What characterizes the output impedance ratio of a common-emitter amplifier: _______________?
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Answer: D. Moderate
Explanation
Common-emitter transistor amplifiers feature an active collector resistor connected in series with the output terminal. The output impedance of this configuration is determined largely by the collector resistor value and transistor output characteristics. This combination results in an output impedance level that is classified by engineers as being moderate. Common-emitter amplifiers provide both voltage and current gain, making them the most widely used transistor configuration. Output impedance represents the internal resistance presented by an amplifier to its connected load circuit. Amplifier configurations include common-emitter, common-base, and common-collector, each offering distinct impedance traits.
Audio preamplifier stages use common-emitter configurations to achieve good voltage gain and moderate output impedance. Impedance matching between amplifier output and load is necessary to maximize power transfer efficiency. Understanding common-emitter properties helps electronics technicians design stable multistage analog amplifier systems. About one describes the output impedance of emitter follower common-collector amplifiers rather than common-emitter circuits. Low output impedance is characteristic of common-collector voltage follower circuits rather than common-emitter amplifiers. High output impedance is typical of common-base current amplifiers rather than standard common-emitter amplifier stages.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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