analog_filter

Analog filter

Some of the applications in this project require an analog filter for DAC to remove quantization noise and to remove DC (AC coupling). The quality of sound is not so good: this filter is just for some experiments on DSP.

• Circuit simulation (LTspice)
• Frequency response (LTspice)
• Circuit schematic (KiCad)

Input signal before the analog filter:

Output signal after the analog filter:

Wirling the analog filter to Arduino connector

• Connect PA4 to left-channel pin header,
• Connect PA5 to right-channel pin header,
• Connect GND to GND pin header, on the analog filter board.

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  [ ]                                [*] PA5(DAC1 OUT2)
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  [*] GND                            [ ]
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  [*] PA4(DAC1 OUT1)                 [ ]
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