AD1934

Rev. 0 | Page 16 of 28

DAISY-CHAIN MODE

The AD1934 also allows a daisy-chain configuration to expand

the system 16 DACs (see Figure 12). In this mode, the DBCLK

stream belong to the first AD1934 in the chain and the last eight

slots belong to the second AD1934. The second AD1934 is the

device attached to the DSP TDM port.

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

AD1934 can be configured into a dual-line, DAC TDM mode,

as shown in Figure 13. 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 AD1934 in the chain and the last four channels belong to

the second AD1934.

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

a 192 kHz sample rate into the AD1934, as shown in Figure 14.

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

serial mode selected. See Table 13 for a detailed description of

the function of each pin. See Figure 18 for a typical AD1934

configuration with two external stereo DACs. Figure 15 and

Figure 16 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 their normal

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 AD1934

DSDATA2 (TDM_OUT)

OF THE SECOND AD1934

THIS IS THE TDM

TO THE FIRST AD1934

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

AD1934

FIRST

AD1934

Figure 12. Single-Line DAC TDM Daisy-Chain Mode (Applicable to 48 kHz Sample Rate, 16-Channel, Two AD1934 Daisy Chain)

DLRCLK

DBCLK

8 DAC CHANNELS OF THE SECOND IC IN THE CHAIN

8 DAC CHANNELS OF THE FIRST IC IN THE CHAIN

DSDATA1

(IN)

DAC L1

DAC R1

DAC L2

DAC R2

DAC L1

DAC R1

DAC L2

DAC R2

DSDATA3

(IN)

DAC L3

DAC R3

DAC L4

DAC R4

DAC L3

DAC R3

DAC L4

DAC R4

DSDATA2

(OUT)

DAC L1

DAC R1

DAC L2

DAC R2

DSDATA4

(OUT)

DAC L3

DAC R3

DAC L4

DAC R4

32 BITS

DSP

SECOND

AD1934

FIRST

AD1934

MSB

Figure 13. Dual-Line, DAC TDM Mode (Applicable to 96 kHz Sample Rate, 16-Channel, Two AD1934 Daisy Chain); DSDATA3 and DSDATA4 Are the Daisy Chain