TPA3130D2: TPA3130D2 1SPW

ling li

Part Number: TPA3130D2
Other Parts Discussed in Thread: TPA3116D2EVM

hi all，

IC: tpa3130d2 PVCC and AVCC = 15V

BD mode, there is no input audio, and the oscilloscope tests any output (single end to ground test) DC = 7.5V, which I think is correct.

1spw mode, no input audio. The oscilloscope tests any output (single end to ground test) and finds that DC = 2.5V. It doesn't feel right. What's the problem?

1psw mode, R51 = ohm, R53 = 5.6k, and the gain is 20dB. I try to input 1kHz sine wave. As expected, the waveform is asymmetrically distorted (single end to ground test).

8547.Schematic Prints.pdf

over 2 years ago

+1 Dylan Yao over 2 years ago

TI__Genius 9140 points

Ling,

at 1SPW mode, the idle duty cycle is less than 50%, which result in DC=2.5V. you can refer to datasheet page 20 for PWM waveform.

you should measure the OUTP-OUTN, instead of OUTP only or OUTN only.

Dylan

0 ling li over 2 years ago in reply to Dylan Yao

Prodigy 10 points

Dylan，

Thank you very much.

The following questions about BD mode.

1. Distortion was found in some bands. why？As shown in the figure below, 1kHz is perfect and 3kHz is distorted. L=22uH，C=0.68uF。

2. I roughly calculated the value of zobel resistor and capacitor. RZ = 10R, CZ = 2.2uf. Is CZ too large? How to determine the power of RZ? 1W? 5W?

0 Yanming Gong over 2 years ago in reply to ling li

TI__Mastermind 19030 points

Hi,

What's the output power when distortion? maybe the output is clipped.

10ohm+2.2uF is not suitable, it will increase idle current. We suggest 10ohm+330pF.

Regards,

Derek

0 ling li over 2 years ago in reply to Yanming Gong

Prodigy 10 points

Hello,

1. There is no clipping, but the waveform is abnormal. Look at the figure of 3kHz, VPP does not reach the clipping voltage.

2. OK, how many watts should I choose for 10ohm?

0 Yanming Gong over 2 years ago in reply to ling li

TI__Mastermind 19030 points

Hi,

1, the distortion may be related to inductor non-linearity.

2, The snubber has no impact to max power.

Regards,

Derek

0 ling li over 2 years ago in reply to Yanming Gong

Prodigy 10 points

Hello!

1. Do you suspect that the distortion is caused by inductance? How to solve it?

2. I mean, how many watts is the zobel resistor RZ? How to calculate? 谢谢。

0 Dylan Yao over 2 years ago in reply to ling li

TI__Genius 9140 points

Ling,

Due to China public holiday, the response will be delayed, will feedback you at Wednesday.

Dylan

0 Yanming Gong over 2 years ago in reply to ling li

TI__Mastermind 19030 points

For snubber calculation, you can refer the below APP note:

https://www.ti.com/lit/an/sloa201/sloa201.pdf?ts=1632273790069&ref_url=https%253A%252F%252Fwww.ti.com%252Fsitesearch%252Fdocs%252Funiversalsearch.tsp%253FlangPref%253Den-US%2526searchTerm%253DSLOA201%2526nr%253D21

Inductor non-linearity is very hard to solve, it is related to the inductor you selected.

BTW, did you add lp filter on oscilloscope when you captured the waveform?

Regards,

Derek

0 ling li over 2 years ago in reply to Yanming Gong

Prodigy 10 points

Hello!

Can you help test the output waveform of tpa3116d2evm in different frequency bands?, I don't have tpa3116d2evm.

Does Ti have any explanatory data on the relationship between inductance parameters and output waveform distortion. I tested a variety of inductors and found that they all have waveform distortion in different frequency bands.

I didn't use LP filter。