User's Manual

LE920A4 HW User Guide Hardware Interfaces
Doc#: 1VV0301261 Audio Interface
Rev. 4.3 Page 85 of 123 2017-12-07
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_DAT
A_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).