What external components are required in order to get a low level signal suitable for a external active subwoofer connected via the subwoofer PWM output of the TAS5706B amplifier?
I can only find examples on how to connect subwoofer amplifiers such as the TAS5602 power stage.
Maybe someone could even provide an example schematic.
I am not sure I follow what you are trying to do.
Do you want to use the TAS5602 for a sub-woofer with the TAS5706?
OR, do you want to use some powered sub-woofer with an analog input?
Audio Applications Engineering Manager
Dallas, TX USA
Sorry for being unclear - I want to connect the subwoofer PWM output of the TAS5706 to a convential (consumer product) active subwoofer, i.e. an ordinary sub with a built in amp of its own. That is, yes I want to use a powered sub with line level analog input.
My question is what component(s) I need to have between the PWM output and the line input of the sub.
I have never tried this, but you should be able to simply LPF (low-pass filter) the PWM outputs with an RC filter and feed it to your amp. I'd set the corner freq around 30 kHz or so.
We often do this with HP (headphone) amps, so I don't expect any issues. For an example, check out the TAS5717 schematic R13/C13 and R9/C20 are these LPF.
That's great, I'll try this. Thank you.
Yes, sorry, I forgot that part. The EVM schematic almost at the end of the EVM Users Guide. It's a little bit complicated b/c there is a jumper that decides the source of the HP - either PWM from the TAS5717, or analog-input from another chip. But, it's got the LPF that I was suggesting.
Remember, you need an LPF in there, and I doubt your sub has fully differential inputs, so you will need to go thru a differential to single-ended conversion, too. But, as a bonus, you can use an active LPF in that case!
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.