Projeto de Amplificador com Realimentação

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Step of 5 11.023P Design a feedback amplifier using a feedback loop connected around a two-stage amplifier. First stage is a direct-coupled small-signal amplifier with a high upper 3-dB frequency. The second stage is a power output stage. The upper 3 dB frequency is, The upper 3 dB frequency is WH = 8kHz The upper 3-dB frequency of the feedback amplifier is = 40kHz Substitute corresponding values. Rewrite the equation. Step of 5 The mid-band gain of the feedback amplifier is, = The mid-band gain of the feedback amplifier should be 100V/V AM Find mid-band gain. Substitute 5 for in the equation. =500 Step 3 of 5 Overall voltage gain of two-stage amplifier is, The mid-band gain is Substitute 500 for AM and 10 for A2 in the equation. Solve for =50 Hence, the required gain of small signal amplifier is 50V/V Step 4 of 5 Determine the value of Substitute for AM Solve for feedback factor 4 Substitute 50 for and 10 for A2 in the equation. (50)(10) 4 = 0.008 Hence, the value of is 0.008 Step of 5 Determine the lower 3-dB frequency of overall amplifier. The lower 3-dB frequency of the feedback amplifier is, = The lower 3 dB frequency is = Substitute 5 for and 80 for in the equation. 80 =16 Hence, the lower 3-dB frequency of overall amplifier is 16Hz