User's Guide

LE920A4 HW User Guide Hardware Interfaces
Doc#: 1VV0301261 Audio Interface
Rev. 4.7.1 Page 85 of 124 2019-11-21
8.6.3. Digital Audio
The module can be connected to an external codec through the digital interface.
The product provides a single Digital Audio Interface (DVI) on the following pins:
Table 37: Digital Audio Interface (DVI) Signals
PAD
Signal I/O Function Type COMMENT
D11 DVI_WA0 O Digital Audio
Interface (WA0)
B-PD 1.8V PCM_SYNC/I2S WS
C8 DVI_RX I Digital Audio
Interface (RX)
B-PD 1.8V PCM_DIN/I2S_DATA_IN
D9 DVI_TX O Digital Audio
Interface (TX)
B-PD 1.8V PCM_DOUT/I2S_DATA_OUT
C10 DVI_CLK O Digital Audio
Interface (CLK)
B-PD 1.8V PCM_CLK/I2S_CLK
C12 REF_CLK O Codec
Reference Clock
B-PD 1.8V I2S_MCLK
The DVI of the module has the following characteristics:
PCM Master mode using short or long frame sync modes
16 bit linear PCM format
PCM clock rates of 256 kHz, 512 kHz, 1024 kHz and 2048 kHz (Default)
Frame size of 8, 16, 32, 64, 128 & 256 bits per frame
Sample rates of 8 kHz and 16 kHz
In addition to the DVI port, the module provides a master clock signal (REF_CLK on Pin
C12) which can either provide a reference clock to an external codec or form an I2S
interface together with the DVI port where the REF_CLK acts as the I2S_MCLK.
The REF_CLK default frequency is 12.288 MHz.
When using the DVI with REF_CLK as an I2S interface, 12.288 MHz is 256 x fs (where fs
= 48 kHz).