TPA3110D2: Sound on delay

Hi,

What's the test points of the outputs? I suggest you should check PWM on output pins.

On the waveforms, the output signal comes from the points OUTPL(25) and OUTLN(23)

Hi

The 15ms is make sense. I do not know why one device has so long time delay.

Does all TAP3110D2 devices have same behavior?

Hi!

At first I thought they were defective chips. I bought different series of chips in different stores and in all cases the TPA3110D2 has a delay, and the TPA3110LD2 has no delay. More than a dozen microcircuits have been tested.

Hi,

Did you check the difference on same board or same design?

 I checked the devices feature, the two devices has same start-on time performance.

And I checked the first waveform, whey the PWM was negative voltage at start-up?

Why the voltage at start at the output of the TPA3110D2 I do not know. Perhaps this is related to the problem? I check in one design, solder TPA3110D2 from the printed circuit board, replace it with TPA3110LD2 and the problem with the delay disappears. Logically, everything rests on low-quality microcircuits, but this is not an isolated case, I bought it in different places. Where and how to buy guaranteed quality TPA3110D2 chips? I am in Ukraine.

Hi 

   Since you tested so many device and with same results, maybe not forces on the quality first. The voltage at the start up is possible related, let's re-do some test first. Please check below things:

    1. The negative voltage at your fist picture Ch2, may because you set AC coupling for the probe of oscilloscope. Please double check. And capture the PWM with PVCC together. The PWM voltage is coming from PVCC directly, they shouldn't be negative.

    2. Please use resistor as the load first to do the test.

    3. Please don't send in audio signal while testing, we just need to check at which point the PWM start to appear.

    4. Please zoom in the PWM waveform, to check if the duty cycle is 50% 

1. Yes, in the previous figures the oscilloscope input was in AC mode. The new figures show that the outputs are positive levels.

2. Used a wire resistor 8 ohm, 50W.

3. In the first figure, the oscillogram is "without an input audio signal."

4. In the second picture  duty cycle PWM  (not ideal 50%)

Hi!

Bought in different places and took a long time. Due to the war, unfortunately, this is not possible. Tell me, where can I buy guaranteed good chips? I'm in Ukraine.

Hi,

Could you contact TI FAE, Sale team of your location for further support?