Difference Between Analog Filter and Digital Filter

DIFFERENCE BETWEEN ANALOG FILTER AND DIGITAL FILTER

Analog Filter

1    Analog filters are used for filtering analog signals.

2    Analog filters are designed with various components like resistor, inductor and capacitor

3    Analog filters less accurate & because of component tolerance of active components & more sensitive to environmental changes.

4    Less flexible

5    Filter representation is in terms of system components.

6    An analog filter can only be changed by redesigning the filter circuit.

Digital Filter

1    Digital filters are used for filtering digital sequences.

2    Digital Filters are designed with digital hardware like FF, counters shift registers, ALU and software s like C or assembly language.

3    Digital filters are less sensitive to the environmental changes, noise and disturbances. Thus periodic calibration can be avoided. Also they are extremely stable.

4    These are most flexible as software programs & control programs can be easily modified. Several input signals can be filtered by one digital filter.

5    Digital filters are represented by the difference equation.

6    A digital filter is programmable, i.e. its operation is determined by a program stored in the processor's memory. This means the digital filter can easily be changed without affecting the circuitry (hardware).