C Gain
Hello
who can give me an example to explain this table, I am really confused.
Thank you
Bo Li
Hi, Bo,
Sorry for the delay. Did you get this figured out?
Basically, what it means is we can adjust the audio quality/supply current consumption. If you can sacrifice some audio quality, you can save some supply current, thus extending battery life.
-d2
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Don Dapkus
Audio Applications Engineering Manager
Dallas, TX USA
Hi Don
As refered the example code "Texas Instruments\AIC3254 CS\DATA\EVM\AIC3254\PLAYBACK\PLAYBACK_LOW_POWER.TXT". I know how to do the compensation when choose PTM and understand the concept of compencetion wiht PTM choosing.
Bo Li .
I want to demonstate ADC and DAc Gain settings. I expected that when input is full scale, the output is full scale too, but when input is 120mv(RMS), the output reahes 500mv(RMS), I don't know where signal are amplified, in adc channle or dac channel? I atteched my script, please help.
I tested DRC function by providing different level sine signals to IN1L,R, the output is not restricted to -24db full scale, it still can be up to full scale 500mv(RMS). Any thing I misunderstand the DRC function? or any code I missed to write? please help to explain.
Gian Test################################################ Software Reset################################################# Select Page 0w 30 00 00## Initialize the device through software resetw 30 01 01################################################
################################################ Clock Settings# ---------------------------------------------# The codec receives: MCLK = 11.2896 MHz,# BLCK = 2.8224 MHz, WCLK = 44.1 kHz################################################# Select Page 0w 30 00 00## NADC = 2, MADC = 2, # dac OSR=64, w 30 0b 82w 30 0c 82w 30 0d 00 40## NADC DIVIDER POWER DOWN, ADC_CLK SAME AS DAC_CLK, AOSR=64W 30 14 40 ################################################
################################################ Signal Processing Settings################################################# Select Page 0w 30 00 00## Set the DAC Mode to PRB_P8 (STERO, DRC, 4 BQ, Interpolation B, RC=8)# DRC not enabled yet(see reg68 default)w 30 3c 08## Set the ADC Mode to PRB_R8(STERO, AGC, 3 BQ, AOSR 64, Decimation Filter B,RC=4)# AGC not enabled yet(see req86,94 default)w 30 3d 08################################################
################################################# ROUT ADC TO DAC################################################# Select Page 0w 30 00 00## Stereo ADC output is routed to Stereo DAC input, BDIV_CLKIN=DAC_CLKw 30 1D 10################################################
################################################ Initialize Codec################################################# Select Page 1w 30 00 01## Disable weak AVDD in presence of external# AVDD supplyw 30 01 08## Enable Master Analog Power Controlw 30 02 00## Set the input common mode to 0.9V. (0x00 is default, full chip common mode 0.9)w 30 0a 00## Select ADC PTM_R3w 30 3d 03## Set the input powerup time to 3.1ms (for ADC)w 30 47 32## Set the REF charging time to 40msw 30 7b 01################################################
################################################ Recording Setup################################################# Select Page 1w 30 00 01## Route IN1L to LEFT_P with 10K input impedancew 30 34 40## Route Common Mode to LEFT_M with impedance of 10Kw 30 36 40# # Route IN1R to RIGHT_P with input impedance of 10Kw 30 37 40## Route Common Mode to RIGHT_M with impedance of 10Kw 30 39 40###################################################################### Unmute Left MICPGA, Gain selection of 0dB to make channel gain 0dB. w 30 3b 00## Unmute Right MICPGA, Gain selection of 0dB to make channel gain 0dB. w 30 3c 00#---------------------------------------------------------------------# above code will be useless, if AGC is used. Let it here, it is original code of TI sample.####################################################################### Select Page 0w 30 00 00## Power up LADC/RADCw 30 51 c0## Unmute LADC/RADCw 30 52 00################################################
################################################ Playback Setup################################################ Select Page 1w 30 00 01## De-popw 30 14 25## Route LDAC/RDAC to HPL/HPRw 30 0c 08 08## Route LDAC/RDAC to LOL/LORw 30 0e 08 08## Set the DAC PTM mode to PTM_P3,4w 30 03 00 00## Power up HPL/HPR and LOL/LOR driversw 30 09 3C## Unmute HPL/HPR driver, 0db driver gain w 30 10 00 00## Unmute LOL/LOR driver, 0db driver gainw 30 12 00 00## Power up HPL/HPR and LOL/LOR drivers#w 30 09 3C## Select Page 0w 30 00 00## DAC => 0dB , L and Rw 30 41 00 00## Power up LDAC/RDAC , route Left channel Left Audio interface data and Right channel Right Audio Interface dataw 30 3f d6## Unmute LDAC/RDACw 30 40 00################################################
for DRC test, following code added after above code
################################################ DRC Setup, this part originally copied from "C:\Program Files\Texas Instruments\AIC3254 CS\DATA\EVM\AIC3254\DRC\DRC_PRB_25.TXT"
#to make sure DRC filter parameters are active, paramters are written to buffer-A and buffer-B as well.################################################# Select Page 0w 30 00 00## DAC => DRC Enabled for both channels,# Threshold = -24 db, Hysteresis = 0 dBw 30 44 7c## DRC Hold = 0 ms,# Rate of Change of Gain = 0.5 dB/Fs'w 30 45 00## Attack Rate = 1.9531e-4 dB/Frame,# DRC Decay Rate =2.4414e-5 dB/Framew 30 46 B6## go to page 44w 30 00 2C## DAC Adaptive filter enabled, Buffer-B in Using, Buffer-A in control interface, Buffer not switched in next framew 30 01 06## Go to Page 46 Buffer-Aw 30 00 2E## DRC HPFw 30 34 7F AB 00 00 80 55 00 00 7F 56 00## DRC LPFw 30 40 00 11 00 00 00 11 00 00 7F DE 00## go to page 44w 30 01 2c## DAC Adaptive filter enabled, Buffer-A in Using, Buffer-B in control interface, Buffer not switched in next framew 30 01 04## go to page 64w 30 00 40## DRC HPFw 30 34 7F AB 00 00 80 55 00 00 7F 56 00## DRC LPFw 30 40 00 11 00 00 00 11 00 00 7F DE 00## go to page 44w 30 01 2c## DAC Adaptive filter enabled, Buffer-A in Using, Buffer-B in control interface, Buffer switched in next framew 30 01 05#
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