ADAU1328

Rev. 0 | Page 19 of 32

DAISY-CHAIN MODE

The ADAU1328 also allows a daisy-chain configuration to

expand the system to 8 ADCs and 16 DACs (see Figure 18). In

of the DAC TDM data stream belong to the first ADAU1328 in

the chain and the last eight slots belong to the second ADAU1328.

The second ADAU1328 is the device attached to the DSP

TDM port.

To accommodate 16 channels at a 96 kHz sample rate, the

ADAU1328 can be configured into a dual-line, DAC TDM

mode, as shown in Figure 19. This mode allows a slower

DBCLK than normally required by the one-line TDM mode.

Again, the first four channels of each TDM input belong to the

first ADAU1328 in the chain and the last four channels belong

to the second ADAU1328.

The dual-line TDM mode can also be used to send data at a

192 kHz sample rate into the ADAU1328, as shown in Figure 20.

There are two configurations for the ADC port to work in

shown in Figure 21. The second configuration is shown in

channels occupy the first eight slots; the second eight slots are

empty. The TDM_IN of the first ADAU1328 must be grounded

in all modes of operation.

The I/O pins of the serial ports are defined according to the

serial mode selected. See Table 12 for a detailed description of

the function of each pin. See Figure 26 for a typical ADAU1328

configuration with two external stereo DACs and two external

stereo ADCs.

Figure 23 through Figure 25 show the serial mode formats. For

maximum flexibility, the polarity of LRCLK and BCLK are

programmable. In these figures, all of the clocks are shown with

DLRCLK

DBCLK

8 DAC CHANNELS OF THE FIRST IC IN THE CHAIN

8 UNUSED SLOTS

8 DAC CHANNELS OF THE SECOND IC IN THE CHAIN

MSB

DSDATA1 (TDM_IN)

OF THE SECOND ADAU1328

DSDATA2 (TDM_OUT)

OF THE SECOND ADAU1328

THIS IS THE TDM

TO THE FIRST ADAU1328

DAC L1 DAC R1 DAC L2 DAC R2 DAC L3 DAC R3 DAC L4 DAC R4 DAC L1 DAC R1 DAC L2 DAC R2 DAC L3 DAC R3 DAC L4 DAC R4

DAC L1 DAC R1 DAC L2 DAC R2 DAC L3 DAC R3 DAC L4 DAC R4

32 BITS

DSP

SECOND

ADAU1328

FIRST

ADAU1328

Figure 18. Single-Line DAC TDM Daisy-Chain Mode (Applicable to 48 kHz Sample Rate, 16-Channel, Two ADAU1328 Daisy Chain)