Designing with the Core - 1.0 English

Audio Clock Recovery Unit LogiCORE IP Product Guide (PG335)

Document ID
PG335
Release Date
2019-05-22
Version
1.0 English

This section includes guidelines and additional information to facilitate designing with the core.

The aud_clk_out is the audio sampling clock signal recovered from the reference clock. This signal is of very low frequency and is used to generate aud_mclk. Hence, an external PLL is always required to generate the aud_mclk in MHz range.

The following equation explains how an aud_clk_out is generated for HDMI:

Aud_clk_out = (Fref * N/(2*CTS)) * (1/OutputDivider)

Fref = RX TMDS Clock frequency

The following equation explains how an aud_clk_out is generated for DisplayPort:

Aud_clk_out = (Fref * Maud/(2*Naud)) * (1/OutputDivider)

Fref = rxoutclk frequency