Topic: Analog Circuits
Linear amplifier with a gain of 30 dB is fed with 1.0 µW power, the output power of the amplifier
- A. 1.0 W
- B. 0 dBm
- C. 30 dBm
- D. - 30 dBm
Answer: B. 0 dBm
Explanation: First, convert the input power to dBm: $1.0~\mu\text{W}=10^{-6}\text{W}=-30\text{dBm}$. The output power is the input power plus the gain in dB: $P_{out}=-30\text{dBm}+30\text{dB}=0\text{dBm}$.