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Installation
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Figure 5. BTL Connection
Figure 6. SE Connection
2.1.4 USB Interface
The TAS5731 registers are accessed through I
2
C bus lines SDA and SCL. The USB circuit and USB
connector on the MC57xxPSIA board facilitates the connection between a host computer and the device.
The EVM USB circuit is powered by the 5V USB line of the host PC and is independent of the power
supplies available on the board. The USB device that is used is a TAS1020B from Texas Instruments.
2.1.5 Digital Audio Interface SPDIF
The Digital Audio Interface SPDIF (RCA/OPTO) accepts digital audio data using the I
2
S protocol. See the
TAS5731 data sheet for more information.
The RCA connector and the OPTO connector are the two SPDIF interfaces on the MC57xxPSIA board.
The jumper JP11 toggles between the OPTO and RCA connector to accommodate the signal source.
When the RCA cable or optical cable is connected and the signal source is powered up, verify that the
SPDIF lock indicator (blue LED5) illuminates, confirming that a viable signal is available to the device.
Install a jumper on JP4 across the middle pin and the pin marked SPDIF to connect the digital source to
SDIN1. Install a jumper on JP5 to connect the digital source to SDIN2.
For detailed information on how the data and clocks are provided to the TAS5717L, see the schematic
appearing at the end of this document and the DIR9001 device data sheet (
SLES198 ).
2.1.6 ADC Interface
In the absence of a digital signal source, the PCM1808 ADC can be used to convert an analog audio
signal to a digital signal to the TAS5717L. The DIR9001 still provides clock signals to the ADC in this
process. A 12 MHz crystal is installed on the MC57xxPSIA board. The ADC is an additional feature of this
board to provide flexibility in sourcing an audio signal to the TAS5731. Review the PCM1808 data sheet
(
SLES177 ) for a detailed description of the ADC on this EVM. Install the jumper on JP4 and J5 across the
middle pin and the pin marked ADC to select ADC as the source for SDIN1 and SDIN2, and finally, install
JP2 and JP3.
6 TAS5731EVM Evaluation Module SLOU331A – December 2011 – Revised August 2014
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