Only the linear phase (default) decimation filter response is supported for the 8 kHz sample rate. Supported processing blocks include bi-quads, digital mixer, and channel summer. The AGC, DRE, or DRC processing block is not supported for the 8 kHz sample rate. Bi-quads, channel summers, and digital mixer blocks are supported on the respective input channels (Table 2-7).

Figure 3-1 shows the analog-channel and digital-channel combinations that can be supported for an 8 kHz sample rate. For example, it can be seen that with two analog channels (third column), up to two digital channels can be supported, whereas with one analog channel also, up to 2 digital channels can be supported. The cell entry indicates the number of bi-quads available for that channel combination. For example, with the combination of two analog and two digital microphones and three bi-quads per channel can be supported.

Figure 3-1 Supported Channel Combinations for 8 kHz to 48 kHz Sample Rates