WM8959 Wolfson Microelectronics Ltd., WM8959 Datasheet - Page 89

• Manufacturer Part Number: WM8959
• Description: Mobile Multimedia DAC with Dual-mode Class AB/D Speaker Driver
• Manufacturer: Wolfson Microelectronics Ltd.

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Pre-Production
DIGITAL AUDIO INTERFACE
The digital audio interface is used for inputting DAC data to the WM8959. It uses three pins:
DACDAT, DACLRC and BCLK functions can also be supported using alternative GPIO pins.
The clock signals BCLK and DACLRC can be outputs when the WM8959 operates as a master, or
inputs when it is a slave (see Master and Slave Mode Operation, below).
Four different audio data formats are supported:
All four of these modes are MSB first. They are described in Audio Data Formats, below. Refer to the
“Electrical Characteristics” section for timing information.
Time Division Multiplexing (TDM) is available in all four data format modes. The WM8959 can be
programmed to send and receive data in one of two time slots.
PCM operation is supported using the DSP mode.
MASTER AND SLAVE MODE OPERATION
The WM8959 digital audio interface can operate as a master or slave as shown in Figure 50 and
Figure 51.
Figure 50 Master Mode
OPERATION WITH ALTERNATIVE DAC INTERFACE
To allow data to be input to the WM8959 DACs from two separate sources, the GPIO[5:3] pins can
be configured as an alternative DAC interface (BCLK2, DACLRC2, DACDAT2) as shown in Figure 52
to Figure 57.
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DACDAT: DAC data input
DACLRC: DAC data alignment clock
BCLK: Bit clock, for synchronisation
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DSP mode
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Figure 51 Slave Mode
PP, May 2008, Rev 3.1
WM8959
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