ZHCSHK8B October 2017 – October 2018 TAS2770
Excessive DC and low frequency content in audio playback signal can damage loudspeakers, so the TAS2770 employs a high-pass filter (HPF) to prevent this from occurring for the PCM playback path. No HPF is available in the PDM playback path. Table 36 below shows the -3 dB corner frequencies available for each sample rate set by register bits HPF_FREQ[2:0]. The filter can be bypassed by setting the HPF_FREQ[2:0] register to 3'b000. The HPF Bi-Quad filter coefficients can also be directly programmed via the TBD register bits.
|HPF_FREQ[2:0]||-3 dB FREQUENCY (Hz)|
|44.1/88.2/176.4 kHz||48/96/192 kHz|
| ||1.8 (default)||2 (default)|