Welcome to the Audio Converters Section of the TI E2E Support Community. Ask questions, share knowledge, explore ideas, and help solve problems with fellow engineers. To post a question, click on the forum tab then "New Post".
Q: DAC32 WCLK Questions
Trying to interface the DAC32 to an SSI port on a Stellaris uC.
This is a native 16bit interface so having problems making a glueless connections.
- If the DAC32 is a slave (MCLK driven by Stellaris 12.5Mhz clock as well), how close does WCLK needbe to 44.1 Khz. before having problems with the digital audio interface? WCLK will have approximately.02% error to 44.1Khz.
- Does the DAC Re-Sync (D2 in Control Register B) help in this case?
- If the DAC32 is in DSP mode, what will it do if it gets a pulse on WCLK right after the left channel SDIN (middle of frame)?The Stellaris team has reported some codecs simply ignore this.
A: Re: DAC32 WCLK Questions
WCLK should be at exactly the sample rate that they want to run at. They can use the internal PLL to derive the Fs Clock from their MCLK. The actual sample rate is set by MCLK, WCLK and BCLK simply clock the data in. Since there is no buffer on the DAC32, if WCLK doesn't match the sample rate set by WCLK and the register settings (PLL etc...), they will either mis samples or clock samples in twice. In either case, you can end up with audible artifacts.
I would recommend using the PLL to match Fs to WCLK exactly, or setting the DAC32 as the master.
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.