TLV320AIC3254_09 Datasheet, PDF (70/168 Pages) Texas Instruments – Ultra Low Power Stereo Audio Codec With Embedded miniDSP

TLV320AIC3254
Ultra Low Power Stereo Audio Codec With Embedded miniDSP
SLAS549A – SEPTEMBER 2008 – REVISED OCTOBER 2008
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Differential
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The headphone amplifiers can be configured differentially as shown in Figure 5-34. However this scheme
is supported only when using the headphone-output stage powered from the AVdd supply.
HPL
HPR
Figure 5-34. Differential Receiver Speaker Configuration
The TLV320AIC3254 supports an additional low-power mode for routing a mono DAC for a differential
headphone configuration as shown in Figure 5-35.
LEFT
DAC AFIR
LEFT_DACP
LEFT_DACM
HPL
HPR
Figure 5-35. Low Power Mono DAC to Differential Headphone
The TLV320AIC3254 headphone drivers support pop-free operation. Because the HPL and HPR are
high-power drivers, pop can result due to sudden transient changes in the output drivers if care is not
taken. The most critical care is required while using the drivers as stereo single-ended
capacitively-coupled drivers as shown in Figure 5-33. The output drivers achieve pop-free power-up by
using slow power-up modes. Conceptually, the circuit during power-up can be visualized as
Output
Driver
Rpop
Cc
PAD
Rload
Figure 5-36. Conceptual Circuit for Pop-Free Power-up
The value of Rpop can be chosen by setting register Page 1, Register 20, D(1:0).
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Application Information
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