Digital Audio Interfaces
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SLOU461 – November 2016
Copyright © 2016, Texas Instruments Incorporated
TAS2557 Evaluation Module
6
Digital Audio Interfaces
The various digital audio interfaces on the TAS2557EVM can be selected through hardware settings and
software settings. Several headers close to the TAS2557 device allow access to the following digital audio
signals:
•
J3: Data Out (DOUT) from the TAS2557 (For example, current and voltage sense data.)
•
J15: Data In (DIN) to the TAS2557
•
J16: Word Clock or Frame Sync (WCLK)
•
J17: Bit Clock (BCLK)
•
J18: Master Clock (MCLK) (This is optional if TAS2557 PLL is not used.)
J3 has two pins:
•
Digital data (for example, I and V sense data) from the TAS2557 device
•
Ground
J15, J16, J17, and J18 have three pins:
•
Digital audio signals from the EVM
•
Digital audio signals to the TAS2557
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Ground
A jumper inserted in position 1-2 connects the TAS2557 to the digital audio signals from the board (for
example, USB or Learning Board 2). Replacing the jumper with a connector from an external source
connects the TAS2557 to the external source (for example, AP or PSIA).
The selection between the two on-board digital audio sources (USB or Learning Board 2) is controlled by:
(a) Hardware: J26,J27
•
J26 = inserted, J27 = inserted; Selects USB
•
J26 = inserted, J27 = removed; Selects Learning Board 2
(b) Software: The PPC3 GUI controls the digital audio routing during speaker characterization. This has
priority over the hardware settings from point a.
The secondary digital audio interface from the TAS2557 device is directly available through J5.
