AudioSerialDataBus
DOUT
GPIO1 GPIO2
MFP3
WCLK
BCLK
DIN
PossibleProcessor Types:
ApplicationProcessor,MultimediaProcessor,
Compressed AudioDecoder,WirelessModem,
BluetoothModule, Additional Audio/VoiceCodec
Processor
2
Processor
1
GPIO2
WCLK
BCLK
DIN
DOUT
MFP3
GPIO1
AIC33
www.ti.com ........................................................................................................................................... SLAS480B – JANUARY 2006 – REVISED DECEMBER 2008
Figure 20. Alternate Audio Bus Mulitplexing Function
In cases where MFP3 is needed for a secondary device digital input, the TLV320AIC33 must be used in I2C
mode (when in SPI mode, MFP3 is used as the SPI bus MOSI pin and thus cannot be used here as an alternate
digital input source).
This mux capability allows the TLV320AIC33 to communicate with two separate devices with independent
I2S/PCM buses. An example of such an application is a cellphone containing a Bluetooth transceiver with
PCM/I2S interface, as shown in Figure 21. The applications processor can be connected to the WCLK, BCLK, DIN, DOUT pins on the TLV320AIC33, while a Bluetooth device with PCM interface can be connected to the
GPIO1, GPIO2, MFP3, and DOUT pins on the TLV320AIC33. By programming the registers via I2C control, the
applications processor can determine which device is communicating with the TLV320AIC33. This is attractive in
cases where the TLV320AIC33 can be configured to communicate data with the Bluetooth device, then the
applications processor can be put into a low power sleep mode, while voice/audio transmission still occurs
between the Bluetooth device and the TLV320AIC33.
Figure 21. AIC33 Connected to Multiple Audio Devices
The audio bus of the TLV320AIC33 can be configured for left or right justified, I2S, DSP, or TDM modes of
operation, where communication with standard telephony PCM interfaces is supported within the TDM mode.
These modes are all MSB-first, with data width programmable as 16, 20, 24, or 32 bits. In addition, the word
clock (WCLK or GPIO1) and bit clock (BCLK or GPIO2) can be independently configured in either Master or
Slave mode, for flexible connectivity to a wide variety of processors
Copyright 2006–2008, Texas Instruments Incorporated
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