phyCORE-OMAP44xx
Part II: PCM-959/phyCORE-OMAP44xx Carrier Board
L-760e_1 © PHYTEC Messtechnik GmbH 2012
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The audio interface provides a method of exploring the OMAP44xx's I
2
S capabilities. The phyCORE-OMAP44xx
Carrier Board is populated with a Texas Instruments low-power stereo audio codec with integrated mono
class-d amplifier (TLV320AIC3007) at U43. The TLV320AIC3007 provides a High Performance Audio DAC and ADC
with sample rates from 8 kHz to 96 kHz. It supports a stereo line input, stereo microphone input, stereo line
output, stereo headphone output, and direct speaker output.
The TLV320AIC3007 is interfaced to the phyCORE-OMAP44xx SOM via the I
2
S interface of the multichannel
buffered serial port's third module (McBSP3) for audio data and the fourth I
2
C interface (I2C4) for codec
configuration (I
2
C address 0x18). Audio devices can be connected to 3.5 mm audio jacks at X14, X15 and X17,
and to expansion connector X5. A detailed list of applicable connectors is presented below.
Audio Outputs:
X14 - Headset Out or Line Output - Line_OUTL/Line_OUTR
X5 - Speaker Out (X5D22 - Speaker negative differential output; X5D23 - Speaker positive differential output)
Audio Inputs:
X15- Microphone Inputs - MIC1/MIC2
X17 - Line Input - Line_INL/Line_INR
Please refer to the audio codec’s reference manual for additional information regarding the special interface
specification.
Jumper J13 allows flexible control over the audio codec's master clock source (MCLK). In the default position
(2 + 3) the codec is clocked from the module's X_FREF_CLK4_REQ clock signal. The audio codec's master clock
can range from 512 kHz to 50 MHz. If J13 is set to 1 + 2 the clock is generated by a crystal oscillator (19,2 MHz)
at OZ1 on the carrier board. See
for jumper configuration settings.
Connector X14 carries either signals from the headset out or the line output of the codec. Jumpers JP15
(right channel) and JP16 (left channel) allow to select the audio source for connector X14. The default
configuration (1 + 2) connects the headset output to X14 (see
for details).
As well the microphone input (X15), as the headset output (X14) allow for jack detection. The jack detection of
the microphone input is hardwired, while jack detection of the headset output can be disabled by jumper J11.
In the default position (2 +3) jumper J11 connects the shield contact of audio jack X14 (headphone out) to
either GND. In this configuration jack detection is disabled. Connecting the shield contact to the HPCOM output
driver of the stereo audio codec at U43 (J11 at 1 + 2) allows to use the jack detection function.
