Datasheet

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SLES101A – DECEMBER 2003 – REVISED NOVEMBER 2006

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External Digital Filter Interface and Timing

The DSD1796 supports an external digital filter interface comprising a 3- or 4-wire synchronous serial port, which allows

the use of an external digital filter. External filters include the Texas Instruments DF1704 and DF1706, the Pacific

Microsonics PMD200, or a programmable digital signal processor.

In the external DF mode, PLRCK (pin 4), PBCK (pin 6) and PDATA (pin 5) are defined as WDCK, the word clock; BCK,

the bit clock; and DATA, the monaural data, respectively. The external digital filter interface is selected by using the DFTH

bit of control register 20, which functions to bypass the internal digital filter of the DSD1796.

When the DFMS bit of control register 19 is set, the DSD1796 can process stereo data. In this case, DSDL (pin 1) and DSDR

(pin 2) are defined as L-channel data and R-channel data input, respectively.

Detailed information for the external digital filter interface mode is provided in the APPLICATION FOR EXTERNAL

DIGITAL FILTER INTERFACE section of this data sheet.

Direct Stream Digital (DSD) Format Interface and Timing

The DSD1796 supports the DSD format interface operation, which includes out-of-band noise filtering using an internal

analog FIR filter. The DSD format interface consists of a 3-wire synchronous serial port, which includes DBCK (pin 3), DSDL

(pin 1), and DSDR (pin 2). DBCK is the serial bit clock. DSDL and DSDR are the L-channel and R-channel DSD data input,

respectively. They are clocked into the DSD1796 on the rising edge of DBCK. PLRCK (pin 4) and PBCK (pin 6) must be

connected to GND in the DSD mode. The DSD format (DSD mode) interface is activated by setting the DSD bit of control

Detailed information for the DSD mode is provided in the APPLICATION FOR DSD FORMAT (DSD MODE) INTERFACE

section of this data sheet.

TDMCA Interface

The DSD1796 supports the time-division-multiplexed command and audio (TDMCA) data format to enable control of and

communication with a number of external devices over a single serial interface.

Detailed information for the TDMCA format is provided in the TDMCA INTERFACE FORMAT section of this data sheet.