www.ti.com
2.5
Master/Slave Mode Operation
2.5.1 Master Mode
2.5.2 Slave Mode
2.6
EVM Default Configuration
Master/Slave Mode Operation
The digital audio outputs can be to I
2
S or SPDIF format optical TOSLINK. The I
2
S output is provided on
connector J9. There are two SPDIF output options. One SPDIF output can be produced by the TAS3308
on SDOUT2. This is set by a TAS3308 I
2
C register configuration option. This output is available on
OPTO3. The other SPDIF output is the SDOUT1 output that is converted into SPDIF format by an external
encoder. This is output on OPTO4.
The TAS3308 has an optical SPDIF input from OPTO2. This is a pass though only connection to the
TAS3308 SDOUT2/SPDIF output on, OPTO3.
The TAS3308EVM is delivered configured to operate in clock master mode. However, the TAS3308 can
be configured as a clock slave or master using JP3.
Table 2-2. JP2 Clock Master/Slave Setting
Jumper JP3 Pins
I
2
S Clock Mode
1, 2
Slave
2, 3
Master
In master mode, the master clock, MCLK SCLK and LRCLK for the system are provided on J9. Data can
be input on the analog input and as I
2
S data on J1.
SPDIF I
2
S input from OPTO1 is not supported in master mode.
Data can be output from the I
2
S outputs on J9, SPDIF I
2
S output, OPTO4, and from SPDIF SDOUT2
when the SDOUT2 is configured for SPDIF output.
In slave mode, data and clocks can be input in the SPDIF I
2
S IN, OPTO1, or the I
2
S input, J1. The SPDIF
input is selected automatically when EVM detects a valid SPDIF signal on OPTO1. If the EVM does not
detect a valid SPDIF signal on OPTO1, then the I
2
S inputs are used.
In slave mode, the TAS3308 ADC requires an external clock input from the I
2
S IN or the SPDIF I
2
S IN for
correct operation. The performance of the ADC is affected by the clock source jitter.
Data can be output from the I
2
S outputs on J9, SPDIF I
2
S output, OPTO4, and from SPDIF SDOUT2
when the SDOUT2 is configured for SPDIF output.
The TAS3308 is placed into the default configuration by receiving a reset. The TAS3308 receives a reset
from the power up circuitry, by pressing the Reset button, or by receiving a reset signal through the USB
interface. Following the receipt of reset, the TAS3308 EVM will load the contents of EEPROM2 and come
up with Mute enabled, clock master mode enabled, and the PWM outputs configured for Comb AD
modulation.
As described in this section, an example PurePath Studio GDE processing flow is supplied that configures
the TAS3308 to support a I
2
S digital PCM input, analog input, digital output, line output , headphone
output and TAS5601 Power Stage for both master and slave mode.
SLEU093 – March 2008
Quick Setup Guide
15
