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Design

You are to design an active filter to meet the specifications listed in Table 4 and using only components listed in Table 5.

Note: For practical reasons, $R_1 + R_2 \geq 2$ k$\Omega$, and C should be no bigger than 0.1 $\mu$F.

 

Table 4: Filter Specs

cutoff fc	1,000Hz
pass band gain	2

 

 

Table 5: Available Components

opamps	LM741
resistors	1, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9,
	4.7, 5.6, 6.8, 8.2, 10 Ohms $\pm10\%$ and decade multiples
capacitors	1, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9,
	4.7, 5.6, 6.8, 8.2, 10 $\mu$F, $\pm10\%$ and decade multiples

 

Ideally, the filter is to reject frequencies in the range 0-1,000Hz, and to pass all other frequencies. This is illustrated in Figure 57.

  

Figure 57: Ideal high-pass filter frequency response.

Note: The frequency specified in Table 4 is in Hz: $\omega_c= 2\pi f_c$.

Of course, it is not possible to achieve this ideal respose, and a realistic Bode diagram of the band-reject circuit is shown in Figure 58. Notice also the non-ideal dropoff at higher frequencies.

  

Figure 58: Simulated high-pass magnitude Bode diagram.

Summarise your design in Table 6.

 

Table 6: Design component values.

R1	R2	R	C

 

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