TPA3106D1EVM: I need the highest possible sound pressure with the input signal of 420mV for a class D amplifier. The speaker has 8 ohms. It should be possible to achieve a higher sound pressure with the TPA3106D1 instead of the TPA3112D

Fritz Herren

Prodigy 120 points

Part Number: TPA3106D1EVM
Other Parts Discussed in Thread: TPA3112D1, TPA3106D1, TPA3118D2, TPA3116D2

over 6 years ago

0 Mike Tripoli over 6 years ago

Genius 3295 points

Hi Fritz,

First, what are you using for a preamp? The input to this device needs a low-impedance to drive the input of the Class D amp (this is pretty much true for all of them) as the input impedance changes with gain. Your preamp should also give you some gain to get the input to the Class D at the right level.

Mike Tripoli

0 Shawn Zheng over 6 years ago

TI__Mastermind 24835 points

Hi Fritz,
From the AMP point of view, I think you want as large output power as possible. Yes, TPA3106D1 can support larger output power than TPA3112D1 Basically. But you need to know that the final max output power actually depends on the system level thermal performance on your board. So you need to pay highly attention to the thermal performance during the PCB layout design.
BTW, TPA3106D1 is a very old device. Why don't you consider TPA3118D2 or TPA3116D2, which can support larger output power. They can be used in PBTL mode for mono output channel application.
Best regards,
Shawn Zheng

0 Fritz Herren over 6 years ago in reply to Mike Tripoli

Prodigy 120 points

Hi Mike
Thank you for your answer
I use the VS1000 as Ogg Vorbis player.
Here the link to the datasheet http://www.vlsi.fi/fileadmin/datasheets/vs1000.pdf .
On page 6 the analog output data are described.
The maximum I measured at the input of the TPA3106D1 is an amplitude of 420mV. This is the maximum level. I can reduce - but it's important how louder the better
Do I have to use an additional preamp?

Here is the scheme part VS1000. https://cloud2.quickline.com/share/54b4500b44e17dcf9795484edc075974e2f57f0e153b18bbdc08f0843d84858854845eb09d8a2774628f82ac66ffd667

I am looking forward to your answer

Fritz

0 Fritz Herren over 6 years ago in reply to Shawn Zheng

Prodigy 120 points

0 Fritz Herren over 6 years ago in reply to Shawn Zheng

Prodigy 120 points

Hi Shawn
thank you for your answer.
The problem is the output level or that I need an additional preamp.
Naturally, I can also take a newer generation - unfortunately it does not solve my problem

Best regards
Fritz

0 Shawn Zheng over 6 years ago in reply to Fritz Herren

TI__Mastermind 24835 points

Hi Fritz,
Thank you for the explanation. So the 420mV input amplitude is for peak value, right? With 36db gain setting, the output amplitude can reach 26.88V peak value. While the max PVCC power supply voltage is 26V for both device. So even a larger input amplitude is used, the output signal is clipped by the PVCC power supply.
Best regards,
Shawn Zheng

0 Fritz Herren over 6 years ago in reply to Shawn Zheng

Prodigy 120 points

Hi Shawn

thanks for the hint
I will try with a generator if I can achieve a greater sound pressure.

It's right - so the 420mV input amplitude is for peak value, at the output I have a level of 25.8V peak. PVCC is 24.5V

Best regards
Fritz

Audio

Audio forum

TPA3106D1EVM: I need the highest possible sound pressure with the input signal of 420mV for a class D amplifier. The speaker has 8 ohms. It should be possible to achieve a higher sound pressure with the TPA3106D1 instead of the TPA3112D