TPA3111D1: Audio performance

Alexandre lazareff

Prodigy 30 points

Part Number: TPA3111D1
Other Parts Discussed in Thread: TAS5805

Hello,

We have a question regarding the audio performance of the TPA3111.

Do you know if there is some power limitation due to the modulation and the speaker ?

Below our results and comparison with a class AB amplifier:

		Sanson class AB amplifier	TPA3111 integrate in our design
Audio signal	Acoustic power (dB SPL)	Power measurement (rms):	Power measurement (rms):
Pink noise	72dB	518mW	160mW
White noise	79dB	872mW	989mW
1kHz sinewave	85,6dB	1W	5W

Power measurement is done directly on the speaker using differential probe for the voltage and a current probe for the current.

We also did the measurement with 2 Fluke 117 RMS multimeter (one for voltage, and one for current) and the results are in the same order of magnitude.

For a 1kHz sine wave, we need 5 watt to deliver 85dB instead of 1 watt with a class AB amplifier.

We need to gain 5dB SPL at 1kHz to meet our requirements, but the amplifier seems to have non linear behaviour.

We did the tests with and without LC filters, and the results are the same

Any advice from your audio experts team ?

Or do you recommend an other amplifier ?

Thanks,

Best regards,

Alexandre

over 7 years ago

0 Xiaolin Qin over 7 years ago

TI__Expert 6295 points

hello, Alexandre,

what is your current mesured SPL value at 1KHZ? not fully understand "gain 5dB SPL at 1KHZ". do you mean frequency response at 1KHZ not meet your application?

Regards
Linda

0 Alexandre lazareff over 7 years ago in reply to Xiaolin Qin

Prodigy 30 points

Hello Linda,

To reach a SPL value of 85.6dB we need to deliver:
1W with Sanson class AB amplifier
5W with TPA3111

Regards,
Alexandre

0 Xiaolin Qin over 7 years ago in reply to Alexandre lazareff

TI__Expert 6295 points

Hello,

would you like to try some digital input Class-D, like TAS5805 there is EQ inside DSP and you can do compensation by your self.

Regards
Linda

0 Alexandre lazareff over 7 years ago in reply to Xiaolin Qin

Prodigy 30 points

Hello,

I am not sure to understand the link between compensation with an EQ and the power performance we have.
Could you please give more detail ?

Regards,
Alexandre

0 Xiaolin Qin over 7 years ago in reply to Alexandre lazareff

TI__Expert 6295 points

what I am talking about speaker response curve compensation. you can look at TI audio amplifier with DSP. www.ti.com/.../sloa263.pdf, page 11, there is EQ tuning introduction.

maybe I understand your point wrong. you want to achieve more output power at 1kHz? what is target output power, PVDD and Load?

Regards
Linda

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TPA3111D1: Audio performance