4.1 CLASSD Interpolator

The CLASSD interpolator embeds three filters with different frequency responses. One of the three filters is used for a given DSPCLK and input sample rate. Refer to Table 4-1 for the filter type corresponding to a given DSPCLK and sample rate.

Interpolation is performed using a combination of Infinite Impulse Response (IIR) and Cascaded Integrator-Comb (CIC) filters. For a given input configuration, the filter’s coefficients are automatically redefined to optimize the filter’s transfer function in order to optimize the audio bandwidth.