TLV320AIC3254-Q1: DAC output in LOL/LOR start to decay from 4KHz

Hi,

I will update thread by wednesday

Douglas:

this waveform is when connect to audio amplifier, you can see  4KHz has significant decay. Maybe it's register configuration issue. Do you happen to have a detailed register configuration guide? Thanks. 

Hi,

I will look into this further tomorrow, but yes in the AIC3254 GUI there are preset script for the recording and playback signal path. You can make edits to blocks and record them in the command line interface tab to update the script later.

Hi Haiwen,

What signal are you using as the input to the device? It is hard to tell what is going on in your time domain scope signal. 

To set the TLV320AIC3254 EVM in playback mode, click on "Playback" under "Typical Configurations" in the main GUI screen. Then, select "High Performance Stereo Playback" and click "LOAD" in the GUI. Then, digital audio should be routed to the headphone output as well as the line output. You can test that it is working by selecting the "USB-AudioEVM" as your audio device on your computer and playing sound, listening through headphones or the line out. Once you know that audio is sending, you can try playing a frequency sweep to see what happens to the signal around 4kHz. 

If you cannot get the GUI working, the script that it generates when you select the setting that I described is as follows:

###############################################
# Clock Settings
# ---------------------------------------------
# The codec receives: MCLK = 11.2896 MHz,
# BLCK = 2.8224 MHz, WCLK = 44.1 kHz
###############################################
#
# Select Page 0
w 30 00 00
#
# NDAC = 1, MDAC = 2
w 30 0b 81 82
#
###############################################

###############################################
# Signal Processing Settings
###############################################
#
# Select Page 0
w 30 00 00
#
# Set the DAC Mode to PRB_P8
w 30 3c 08
#
###############################################

###############################################
# Initialize Codec
###############################################
#
# Select Page 1
w 30 00 01
#
# Disable weak AVDD in presence of external
# AVDD supply
w 30 01 08
#
# Enable Master Analog Power Control
w 30 02 00
#
# Set the input powerup time to 3.1ms (for ADC)
# w 30 47 32
#
# Set the REF charging time to 40ms
w 30 7b 01
#
###############################################

###############################################
# Playback Setup
###############################################
#
# Select Page 1
w 30 00 01
#
# De-pop
w 30 14 25
#
# Route LDAC/RDAC to HPL/HPR
w 30 0c 08 08
#
# Route LDAC/RDAC to LOL/LOR
w 30 0e 08 08
#
# Power up HPL/HPR and LOL/LOR drivers
w 30 09 3C
#
# Unmute HPL/HPR driver, 0dB Gain
w 30 10 00 00
#
# Unmute LOL/LOR driver, 0dB Gain
w 30 12 00 00
#
# Select Page 0
w 30 00 00
#
# DAC => 0dB
w 30 41 00 00
#
# Power up LDAC/RDAC
w 30 3f d6
#
# Unmute LDAC/RDAC
w 30 40 00
#
###############################################

Let me know if this answers your question or if there is still an issue with your DAC output. 

Regards,
Mir Jeffres

Jeffres:

I apply one EVM for testing, I want to know if use USB connect to PC, how to choose sound source in TLV320AIC3254 CS, I just found 3254 CS has analog input and don't found USB input like PPC3 showing in below. Thanks.

Hi,

I am out of office for the rest of the week but I will get back to you at the latest by Monday. Thanks for your understanding.

-Mir

Hi,

The EVM should establish itself as an audio output device on your computer by default, without using the EVM software. It doesn't show up as a separate source into the codec in the analog inputs screen of the software since audio from the computer via USB would be classified as digital audio into the codec. In that way, it bypasses the ADC of the device and just sends the computer digital audio out through the DAC, or the DSP then the DAC. You should be able to play audio through the codec without using the software and just by selecting the "USB-AudioEVM" in your Windows sound settings as the output device on your computer. If this results in no sound output, load the "High Performance Stereo Playback" preset in the "Playback" configurations screen in the software. 

If you need to test sound in or out of the device that came through the ADC, I recommend using a 3.5mm aux cable connected to the microphone input jack on the EVM from the headphone output of your computer, and playing sound through your computer as if the cable connected was headphones.

I hope this helps and let me know if you have any more questions.

Best,
Mir