4. A low-noise amplifier has a resistive source of 50 ohms and operates at standard temperature of 290 K. The amplifier has a noise temperature of 120 K and a noise-effective- bandwidth of 50 kHz. a) What is the noise power available from the source at the input of the amplifier. Give your results in dBm? b) How much noise power is added by the amplifier ? Give your results in dBm. c) If the amplifier has a gain of 15 dB, and a -120 dBm signal is applied to the input of the amplifier, what is the SNR in dB at the output of the amplifier? d) What is the overall noise figure in dB? e) How much signal power in dBm is available at the output of the amplifier?

4. A low-noise amplifier has a resistive source of 50 ohms and operates at standard temperature of 290 K. The amplifier has a noise temperature of 120 K and a noise-effective- bandwidth of 50 kHz. a) What is the noise power available from the source at the input of the amplifier. Give your results in dBm? b) How much noise power is added by the amplifier ? Give your results in dBm. c) If the amplifier has a gain of 15 dB, and a -120 dBm signal is applied to the input of the amplifier, what is the SNR in dB at the output of the amplifier? d) What is the overall noise figure in dB? e) How much signal power in dBm is available at the output of the amplifier?

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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Similar questions

Give the input and output impedances for an ideal-voltage amplifier. Repeat for each of the other ideal amplifier types.
1.Syeda and Urmi are two friends who are doing a class in the course of Electrical Drives and Instrumentation. One day when they studied together in a virtual environment about the instrumentation amplifier, then Urmi said to Syeda that Noise is the main enemy of this amplifier. So, we have to solve this problem. How can they solve the problems of noise in this amplifier? Syeda said that if they use high CMRR then this problem can be minimized. Are you agree with Syeda? Give necessary information. 2.Suppose you are working on a dc motor in your laboratory. At the start of the motor, you are using a starter circuit, and when the motor is geared up with the full speed, then the starter is removed from the circuit. After a while, you observe that the field circuit of a motor is open-circuited. What may happen under this condition? How can you solve this problem?
None
QUESTION 2 An amplifier has equivalent thermal input noise sources of Sny/ and 10pA/VHz. It has a voltage gain of 10, a noise Bandwidth of 10MHZ. and a high input impedance. What would its noise figure be if driven by a source with an impedance chosen to minimise the amplifier noise figure? Enter your numeric answer to 3 significant figures (no units).
1. A certain class “A” amplifier has a DC Supply power of 2 W, the maximum output power available from this amplifier is 500 mW. Calculate:a. The maximum efficiency, ηmax for this amplifier in percentage.b. If the input power is increased from part “a” such that it results in the clipping in the negative cycle of the output waveform then clearly identify the reason for this performance, stating the location of the Q-Point.
Q.) Do all parts of the given Question
2.A. Using an operational amplifier draw the circuit diagram of a noninverting amplifier with a voltage gain of 25. Show all power supply connections, input and output voltages, and give appropriate values for the resistors. - B. If the voltage gain is increased to 200, what effect will this change have on the bandwidth of the amplifier and why is this so? {C. If the resistance of the transducer connected to the input of the noninverting amplifier is increased from 50 ohms to 50k ohms, what effect will it have on the voltage gain of the amplifier. D. What effect will the change in transducer resistance from 50 ohms to 50k ohms have on the output and why is this so?
Q.2/ For the amplifier's circuits shown below: a. Determine the Q-point for each amplifier circuit. b. What is the maximum peak value of collector current that can be realized in each circuit? c. What is the maximum peak value of output voltage in each circuit? +12 V +12 V RC C3 RC C3 R1 6802 R 12 k 100 N Vout 470 2 Vut 10 μ 10 μF V RL 1002 10 μF 10 µF REi 4.7 N REI 22 Ω2 R2 510 n RE2 75 0 C2 10 uF R2 4.7 kN RE2 120 N C2 RL 10 uF 470 N (a) Be = Bpc = 125 (b) Bac = BDc = 120
Q1/ Choose the correct answer 2- The output of the non-inverting amplifier a. Is in phase with the input. b. Increases with the input c. Cannot be greater than the supplied voltage. d. All of the above. 3- The purpose of negative feedback is to a. Reduce the number of components in an amplifier b. Increase the transistor life c. Improve the gain and bandwidth of an amplifier d. Limit the amplifier output. 4- When a feedback voltage produces an increase in impedance, it is an example of......... a. Impedance compensation. c. Gain suppression. b. Shunt negative feedback. d. Series negative feedback 5- If a loud speaker with a resistance of 2 Ohms and a 10Vrms voltage drop is the output of a single-ended power amplifier, what is the output power of the amplifier? b. 25mW a. 50 W c. 2W d. 20W
4. A two-stage amplifier has the following frequencies, first stage: 100 Hz, 200 Hz, I kHz, 4 kHz, second stuge: 300 Hz, 500 Hz, 8 kltz, 10 kHz. The bandwidth is: a) 7.5 klz b) 3 kHz e) 3.5 kL. d) 9.5 kHz 5. If the gain-bundwidth product of an amplifier is 100 Mtz and the bandwidth 50 MŁz, the midrange voltage gnin is: a) 2 dB b) 6 dB c) 0.5 dB d) 20 dB 6. When the output voltage of an amplifier at the eritieal frequency is 35.5 V, the voltage at midrange is: a) 50 V b) 47 V e) 25 V d) 71 V 1. If penk output power of an amplifier is 20 W. the power at critical frequeney is a) 14.14 W b) 28.28 W c) 10 W d) 20 W 8. At high frequency operation of an amplifier, the internal capucitances of the BUT transistor are determined from: a) The input and output Miller capacitances b) The input and output coupling cupacitances e) The bypass capacitance d) The capacitances values in the data sheet
1 Draw the diagram of an Operational Amplifier with proper labelling. Comment about Differential Gain and Common Mode Gain of an Operational Amplifier. Discuss how the above mentioned gains decide the performance standard of the Operational Amplifier in comparison to other operational amplifiers. Assume a Scenario: We have two audio amplifiers. Amplifier A: Amplifier A is an audio amplifier utilizing a double ended operational amplifier the output is 20 mV, 50 Hz when two different signals of magnitude 1.5 mV and 2 mV are applied as inputs. While if the same signal of magnitude 1.5 mV is applied to both the inputs the output is 1.7 mV. Amplifier B: Amplifier B is also an audio amplifier utilizing a double ended operational amplifier whose output is 25 mV, 50 Hz when two different signals of magnitude 1.5 mV and 2 mV are applied as inputs. While if the same signal of magnitude 2 mV is applied to both the inputs the output is 2.5 mV. Compare the above two Amplifiers and state which is a…