2.4 Filter for DAC

This filter is an 8-order Butterworth low-pass filter with 1V/V gain. The cut-off frequency is designed to be 4kHz with 0.5dB allowable pass band ripple.

Figure 2-6. 8-order Low-pass Chebyshev Filter

As shown in the figure below, the curve is based on measured data of the filter on the board.

Figure 2-7. Gain vs. Frequency Curve for the 8-order Low-pass Filter