{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

prelab5_soln

prelab5_soln - Physics 3330 Prelab 5 solutions 1(A B The...

This preview shows pages 1–3. Sign up to view the full content.

Physics 3330 Prelab 5 solutions 1 (A & B). The circuit of interest is shown in Figure 1 Figure 1: Active band pass filter. The design goals for the circuit are a resonant frequency of 16 kHz, a closed loop gain of - 1, and a Q of 10. Note that the resonant frequency is f 0 , not ω 0 which is the resonant angular frequency which is measured in rad/s rather than Hz. Also, the closed loop gain is G which is the gain of the circuit as a whole, namely V out /V in . From the theory section we therefore know: f 0 = 1 2 π LC = 16 kHz (1) Q = 1 r L C = Z 0 r = 10 (2) G ( ω peak ) = - Q Z 0 R = - 1 (3) (4) We will use the 10 mH inductor so L = 10 mH and so we can solve for the other values: C = 1 L (2 πf 0 ) 2 = 1 0 . 01 H(2 π (16 × 10 3 Hz)) 2 = 9 . 9 nF = 0 . 01 μ F (5) Z 0 = r L C = r 0 . 01 H 1 × 10 - 8 F = 1000 Ω (6) r = Z 0 Q = 1000 Ω 10 = 100 Ω (7) R = QZ 0 | G ( ω peak ) | = 10 · 1000 Ω 1 = 10 k Ω (8) (9) The final part of part B also asks for the two 3 dB frequencies. While it is possible to solve the full gain equation for these frequencies, it is simpler to use Q = f/ Δ f which gives Δ f = f/Q = 16 kHz / 10 = 1 . 6 kHz. Since Δ f = f + - f - , f ± = f ± Δ f so f - = f - Δ f/ 2 = 16 kHz - 0 . 8 kHz = 15 . 2 kHz and f + = f + Δ f/ 2 = 16 kHz - 0 . 8 kHz = 16 . 8 kHz. 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2. We now add positive feedback (output connected to the non -inverting input) as shown in Fig. 2 Figure 2: Active band pass filter plus positive feedback to make an LC oscillator.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 4

prelab5_soln - Physics 3330 Prelab 5 solutions 1(A B The...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online