DA7218 Datasheet, PDF (70/173 Pages) Dialog Semiconductor – Ultra-Low Power Stereo Codec

DA7218
Ultra-Low Power Stereo Codec
The internal serialized DAI data is 24 bits wide. Serial data that is not 24 bits wide is either shortened
or zero-filled at input to, or at output from, the DAI’s internal 24-bit data width. The serial data word
length can be configured to be 16, 20, 24 or 32 bits wide using the dai_word_length register bits.
Four different data formats are supported by the DAI. The data format is determined by the setting of
the dai_format register bits.
● I²S mode
● Left justified mode
● Right justified mode
● DSP mode
Time division multiplexing (TDM) is available in any of these modes to support the case where
multiple devices are communicating simultaneously on the same bus. TDM is enabled by asserting
the dai_tdm_mode_en bit.
9.8.1 DAI Channels
The DAI supports one to four channels, even in non-TDM modes. The number of channels required
is specified by setting dai_ch_num bit which controls the position of the channels as shown in Figure
34.
BCLK
WCLK
DATIN/
DATOUT
DATIN/
DATOUT
DATIN/
DATOUT
DATIN/
DATOUT
Channel 1L
Channel 1L
Channel 1L Channel 2L
Channel 1L Channel 2L
Channel 1R
Channel 1R
Channel 1R Channel 2R
Channel 1L
DAI_CH_NUM = 1
Channel 1L
DAI_CH_NUM = 2
Channel 1L Channel 2L DAI_CH_NUM = 3
Channel 1L Channel 2L DAI_CH_NUM = 4
Figure 34: Effect of dai_ch_num Bit on DAI Channel Positions (Non-TDM Mode)
In TDM mode, each of the four channels can be individually enabled using the dai_tdm_mode_en bit
as shown in Figure 35.
BCLK
WCLK
DATIN/
DATOUT
DATIN/
DATOUT
DATIN/
DATOUT
DATIN/
DATOUT
DATIN/
DATOUT
DATIN/
DATOUT
Channel 1L
Channel 1L
Channel 2L
Channel 1L Channel 2L
Channel 1L Channel 2L
Channel 1R
Channel 1R
Channel 1R Channel 2R
Channel 1L
DAI_TDM_CH_EN = 1
DAI_TDM_CH_EN = 2
Channel 1L
DAI_TDM_CH_EN = 3
Channel 2L DAI_TDM_CH_EN = 4
Channel 1L Channel 2L DAI_TDM_CH_EN = 5
Channel 1L Channel 2L DAI_TDM_CH_EN = 15
Figure 35: Effect of dai_tdm_ch_en Bit on DAI Channel Positions (TDM Mode)
Datasheet
CFR0011-120-00
Revision 2.5
70 of 173
01 Sep 2016
© 2016 Dialog Semiconductor