AMP Selection

Hi Daniel,

I would suggest:

• TAS2110 if looking for QFN package
• TAS2562 similar to TAS2110 but in WCSP package
• TAS2563 features both QFN and WCSP, as well as integrated DSP for audio processing and speaker protection

All the options above have integrated boost and Class-H as well.

Class-H feature is basically providing an automatically adjustable higher voltage rail for the Class-D driver, this improves frequency as the Class-D is powered only from the required voltage instead of always being connected to a high voltage rail.

You can get more details from this app note: https://www.ti.com/lit/an/slaa888/slaa888.pdf

Best regards,
-Ivan Salazar
Applications Engineer

Hi Ivan, our application does not require the Class H boost functionality.

What would be your recommendation between the following:
TAS2770 - 1.8V IO voltage
TAS5722L - 1.8V IO voltage
TAS5720x - 3.3V IO voltage

Hey Daniel,

Sorry for delay, Ivan has been occupied by his other job functions, but he will respond by end of day

Best Regards,

Carson

LPA Applications Engineer

Hi Daniel,

I think it depends on how much power you need at the load, and if IV-sense is a requirement.

Just to make sure, you mentioned PVDD = 5V, and the devices that you suggest above are usually connected to higher voltage rail. What is your PVDD voltage rail?

Best regards,
-Ivan Salazar
Applications Engineer

We do not have a power specification in mind as of right now. We currently do not have an IV sense requirement - what applications require this?

Our application is related to home robotics and it would be a small mono 4-8 ohm speaker system.

Our PVDD rail is the output of a buck converter = 5V0 - ideally, this should not be changed.

Based on supply chain and our design, the following look to be the best fit
TAS2770 - 1.8V IO voltage
TAS5722L - 1.8V IO voltage

Do you recommend either of these drives? Is one better for our application?

Hi Carson, thanks for the response and recommendation.

I am trying to understand why the TAS2770 or TAS5722L wouldn't be as good of fits for our application. Their power rail can go down to 4.5V.

Kindly let me know and if possible, please address the difference between the two proposed devices.

Hello,

If you dont use high voltage rails there is no point to using these over TAS2505. What is the application?

Best,

Carson

Application is home robotics.

Is it disadvantageous to use an amp like the TAS2770 or TAS5722L in any way? 

Hello,

Right now our experts are out of office until Dec. 28th due to Holidays. We will get back to your question as soon as possible when we resume operations.

Happy Holidays

LPA Applications Team

Hi Daniel,

The main reason you wouldn't use a higher voltage rated amplifier for lower voltages is because of efficiency. Class-D amplifiers are specially efficient at higher voltage and higher power levels, but in some cases considerably less efficient at low levels. You may see this from efficiency plots on both TAS2770 and TAS5722L at VDD = 5V.

Regarding TAS2770 vs TAS5722L, each one has pros and cons (I personally know TAS2770 better and TAS5722L not so much):

• TAS5722L requires less voltage rails
• TAS2770 features IV-sense
• TAS2770 features spread spectrum mode for improved EMI
• TAS2770 features PDM interface

As you can see, TAS2770 has additional features that can be useful if needed, otherwise you can just compare performance for the specific power and supply voltage ranges you're considering and make a decision between these two.

IV-sense is used in some applications to know the state of the speaker in terms of voltage and current in real time. This can be used to calculate the estimated temperature of the coil and also diaphragm excursion if you have the correct model of the speaker.

Best regards,
-Ivan Salazar
Applications Engineer

Hi Ivan, thank you for the above. We will go with one of the above:
TAS2770
TAS5722L
TAS2505

A few questions:
Does the TAS5722L have any specific power sequencing requirements? It looks like the TAS2770 does not?
I am still having difficulties understanding why the TAS2505 is recommended. Based on the efficiency plots of all 3 devices. Both the TAS2770 and TAS5722L are more efficient at 4 and 8 ohm loads at VIN = 5V. It looks like the TAS2770 is actually most efficient of the 3. Please explain.
Regarding your point "TAS5722L requires less voltage rails" - they both require 2 rails for our app - 1.8 and 5V
Regarding your point "TAS2770 features PDM interface" - can this be used as a microphone input then? We are also using the PCMD3140 in our app. What is the SNP002770?

Thank you for your patience thus far.  Hopefully, we can come to a conclusion and have resolution on what device is best for our app.

Hi Daniel,

• TAS5722L does require a specific sequence, but some details about its POR are included in data sheet section 7.4.7
• Taking a closer look, I agree with you, TAS2770 is showing better performance even at lower supply levels. I was still considering as if you needed low power while still having a higher supply voltage rail.
  Another thing to consider would be the price, I can only talk for the prices on ti.com but being TAS2770 more capable in terms of output power and voltage range, it would be more expensive as well.
• Correct, both require 1.8V and 5V, I was mostly considering the variety of supply connections to the device and the required decoupling for each one. TAS2770 requires IOVDD and AVDD as separate rails in addition to VBAT while TAS5722L needs DVDD only and AVDD to PVDD shorted together
  If PCB routing and space is not a concern I would say either option is equally good.
• PDM interface in TAS2770 is for playback purposes only, so if you're using PCMD3140 for recording into a host it would not be replaceable.
• SN are custom parts, based on the same functionality

Best regards,
-Ivan Salazar
Applications Engineer

Please see my responses below:

• TAS5722L does require a specific sequence, but some details about its POR are included in data sheet section 7.4.7
  • Can you specify the sequencing order? I do not see any specific details
• Taking a closer look, I agree with you, TAS2770 is showing better performance even at lower supply levels. I was still considering as if you needed low power while still having a higher supply voltage rail.
  Another thing to consider would be the price, I can only talk for the prices on ti.com but being TAS2770 more capable in terms of output power and voltage range, it would be more expensive as well.
  • Understood
• Correct, both require 1.8V and 5V, I was mostly considering the variety of supply connections to the device and the required decoupling for each one. TAS2770 requires IOVDD and AVDD as separate rails in addition to VBAT while TAS5722L needs DVDD only and AVDD to PVDD shorted together
  If PCB routing and space is not a concern I would say either option is equally good.
  • Understood.
• PDM interface in TAS2770 is for playback purposes only, so if you're using PCMD3140 for recording into a host it would not be replaceable.
  • Understood. Can you elaborate on what applications this would be useful for?
• SN are custom parts, based on the same functionality
  • Understood

Hi Daniel,

My first reply has a typo, sorry for the confusion:

• TAS5722L does not require a specific sequence, but some details about its POR are included in data sheet section 7.4.7

Best regards,
-Ivan Salazar
Applications Engineer