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TLV320DAC3100: Using CC3220 I2S application with Audio DACs

Part Number: TLV320DAC3100
Other Parts Discussed in Thread: TLV320DAC32, TAS2505, LM4819

Hi, guys. The TI's Wi-Fi CC3220 has this feature; McASP Supports Two I2S Channels

Thanks to TI's example code for I2S, I was looking for a audio DAC which supports I2S to play WAV files.

I'm new with audio DACs and I have some questions, please.

I'm trying to stream WAV files via Wi-Fi and play this using TI's audio DAC products. WAV files can be MONO or STEREO.

Instead of using the 3.5mm headphone jack, I'm thinking of using a SMT speaker because I have to create a custom PCB.

So I wish to test with these SMT speakers.

SMS-2008MS-R Resonant frequency 850Hz, 0.8W, 8 Ohms
SW200908-1 900Hz 1.5W 90dBA 8 Ohm

SM150808-8 850Hz, 1W, 8 Ohm

Additionally, this PCB will be using micro USB 5V power supply.

Q0. Considering the USB 5V supply and WAV file streaming applications,

what should I choose;

TLV320DAC3100

TLV320DAC32

?

Q1. I don't know which to choose;

TLV320DAC3100

TLV320DAC32

First of all, will these audio DAC work with CC3220's I2S for playing WAV files?

Q2. I'm just trying to play WAV files with one SMT speaker. Do those speaker will work with these

TLV320DAC3100

TLV320DAC32

chips?

  • Hi, David,

    The TLV320DAC3100 would be a good option. However, I would suggest to take a look at the TAS2505 too. Both devices support I2S mode (2s-complement, signed data, which is the same format than the wav data).

    Both devices support the speaker load that you are attempting to use. However, the TAS2505 supports internal LDO. So, you may use your 5V power supply to power the most part of power pins (AVDD, DVDD, SPKVDD). IOVDD would need to be powered up by another supply depending of the I2S/I2C lines (usually 1.8V or 3.3V).

    Please take a look at these devices and let me know if you have additional questions or comments.

    Best regards,
    Luis Fernando Rodríguez S.

  • Thanks for your kind reply, Luis!  Thanks for recommending  TAS2505.

    Luis Fernando Rodriguez S. said:
    Both devices support I2S mode (2s-complement, signed data, which is the same format than the wav data).

    Q0. Speaking of "WAV data format support", do you mean are there specialized audio DAC (with  from TI which supports WAV, ADPCM (adaptive differential pulse-code modulation), MP3, Opus, etc?

    Q1. The main difference between the TLV320DAC3100 and the TAS2505 is that TAS2505 has a different DAC, right?

    The title of the TAS2505 is "TAS2505 Digital Input Class-D Speaker Amplifier With Audio Processing" and I noticed that

    in the TAS2505's datasheet, the block diagram mentions the DAC.

    So the main difference is the performance of the DAC, then?

    Q2.

    Luis Fernando Rodriguez S. said:
    So, you may use your 5V power supply to power the most part of power pins (AVDD, DVDD, SPKVDD)

    You mean when using  TAS2505, connect IOVDD to 3.3V (CC3220 MCU is also powered with 3.3V)

    SPKVDD (Class-D speaker driver power supply) to 5V

    and LDO_SEL to 5V (SPKVDD) so that the internal LDO provides

    1.8V to AVDD and DVDD, right?

    Q3. If I use a 3.7V Lipo battery instead of a 5V supply later to make this as a portable device,

    connecting SPKVDD (Class-D speaker driver power supply) to 3.3V and LDO_SEL to 3.3V (SPKVDD) also works, right?

  • Hi, David,

    A0. All our audio DAC devices support I2S protocol and some variants like left-justified, right-justified, DSP and TDM modes. Basically, the mode depends the moment when the data is being sent depending of the WCLK rising or falling edge. In all the modes, the supported data must be in 2's complement and signed. The most part of our audio CODECs support 16, 20, 24 and 32 bits format. As far as I know, MP3 or Opus data has another kind of format, so you would require a pre-processing stage to change it to the correct format.

    A1. The DAC performance is slightly different in both devices. TAS2505 supports 2W into 4ohms or 1.7W into 8ohms and TLV320DAC3100 supports 2.5W into 4ohms or 1.6W into 8ohms. I also suggest you to check the electrical characteristics and typical characteristics sections for more details about the output power and the THD+N parameters.

    In addition, both devices support mono Class-D speaker driver, but the TLV320DAC3100 supports stereo DAC. You may select one of both DACs to output the signal through the Class-D driver or even mix both channels.

    TAS2505 also supports SPI protocol and integrated LDO. It has a 24 pins VQFN package. The TLV320DAC3100 has a 32 pins VQFN package.

    A2. You are correct. IOVDD should be tied to a 3.3V power supply and the LDO supply can power on the AVDD and DVDD power pins if LDO is selected. Please take a look at the 5V LDO section for details: http://www.ti.com/lit/ds/symlink/tas2505.pdf#page=21

    A3. Do you refer that LDO_SEL and SPKVDD would be connected to different power supplies? It is not recommended to separate the LDO_SEL and SPK_VDD to different supplies. As stated in the datasheet, they both need to be connected to the same supply. I would recommend to take as reference the figure 22 for the correct LDO connection: http://www.ti.com/lit/ds/symlink/tas2505.pdf#page=27

    I hope this helps. Please let me know if you have additional questions or comments.

    Best regards,
    Luis Fernando Rodríguez S.

  • Thanks, Luis!

    Luis Fernando Rodriguez S. said:
    As far as I know, MP3 or Opus data has another kind of format,

    Got it; I will take a look at this note from TI as well.

    http://www.ti.com/lit/an/spma076/spma076.pdf

    May I add a few more things before closing?

    Luis Fernando Rodriguez S. said:
    I also suggest you to check the electrical characteristics and typical characteristics sections for more details about the output power and the THD+N parameters.

    Q0. May I ask what do you mean by "THD+N" parameters? You mean "Total Harmonic Distortion plus Noise"?

    Also, do you mean check the THD+N of the TAS2505 or the SMT speaker?

    I do notice "THD+N (Total harmonic distortion + noise, 0-dBFS input, 1-kHz input signal) –78.2 dB" from the TAS2505"s data sheet and

    "THD+N (Total harmonic distortion + noise, 0-dBFS input) –82 dB" from the TLV320DAC3100.

    Q1. Just in case, the lower the THD+N value, the better, right?

    Q2. 

    Luis Fernando Rodriguez S. said:
    Do you refer that LDO_SEL and SPKVDD would be connected to different power supplies? It is not recommended to separate the LDO_SEL and SPK_VDD to different supplies.

    Thanks for your correction. I was thinking connecting 3.3V to both LDO_SEL and SPKVDD.

    Just for double-checking, connecting both the LDO_SEL and SPKVDD to 3.3V is acceptable, right?

    Q3. 

    Luis Fernando Rodriguez S. said:
    so you would require a pre-processing stage to change it to the correct format.
     

    Come to think of it, I'm working with WAV files now. Since this doesn't need pre-processing or decoding,

    does this mean I only need the audio amp, not the DAC/DSP in the TAS2505? Or should I use like LM4819 instead?

  • Hi, David,

    A0. Yes, I was referring to the Total Harmonic Distortion + Noise. Both devices have a different performance in this parameter. You may see the differences in the typical characteristics sections.

    http://www.ti.com/lit/ds/symlink/tas2505.pdf#page=15

    http://www.ti.com/lit/ds/symlink/tlv320dac3100.pdf#page=14

    A1. Please notice that there are many parameters such the output power and the power supply voltage that may affect the THD+N level. As you mentioned, the lower the THD+N value, the better.

    A2. It would be acceptable. However, you must consider that if the SPKVDD voltage is decreased, the output power will be lowered too. We can see this behavior in figures 10 and 12 of datasheet: http://www.ti.com/lit/ds/symlink/tas2505.pdf#page=15

    A3. The DAC is required to sample the signal through the serial data interface. It will be necessary to convert the digital signal to the Class-D signal. I was referring to the different protocols that the MP3 or other formats require. In case of the WAV audio format, the TAS2505 or TLV320DAC3100 will be able to perform the audio sampling since it is in 2's complement / signed format.

    Both the TLV320DAC3100 and TAS2505 also works as Class-D Speaker Amplifiers. There won't be need to connect an external amplifier unless you are looking for more output power.

    Best regards,
    Luis Fernando Rodríguez S.