2x100W TPA3116D2 (2 chips, each in PBTL)

[CyberPit]

Hi CyberPit; The driver works just fine but there is a new issue I did not have checked before. At MAX volume (or very high volume) the amp module switches between mute and un-mute states so the out put sound starts and stops repeatedly. Kind of turning on and off the amp very quickly. This does not happen at low volume. Do you have any idea why? Does it have anything to do with input voltage? Thank a lot.

Hi farhad-San,
I guess you are using the UN-regulated power supply, so the supply voltage might be dropped at the big output swing.
Decreasing zener voltage will expand the tolerance of supply voltage drop (allowance level). On the other hand, this change will increases the risk of shut-off pop occurs.

Another possibility of the reason is Over-Current Protection which has an original feature of TPA3116D2 if you connect the very low impedance speaker loads...

 

[farhad]

Hi farhad-San,
I guess you are using the UN-regulated power supply, so the supply voltage might be dropped at the big output swing.
Decreasing zener voltage will expand the tolerance of supply voltage drop (allowance level). On the other hand, this change will increases the risk of shut-off pop occurs.

Another possibility of the reason is Over-Current Protection which has an original feature of TPA3116D2 if you connect the very low impedance speaker loads...

Dear CyberPit; I use an unregulated linear power supply (12V rectified=almost 18V). When I disconnect the driver and go back to the original setup this severe on-off does not happen. It happens only at high volume when the driver is connected.

 

[alephotos]

Hi, has anyone tried or modifier this version?
Thanks

 

[CyberPit]

Dear CyberPit; I use an unregulated linear power supply (12V rectified=almost 18V). When I disconnect the driver and go back to the original setup this severe on-off does not happen. It happens only at high volume when the driver is connected.

farhad-San,

If you feel too sensitive to detect the short term supply voltage drop, you can modify the circuit like this way...

 

[jemraid]

Hi, has anyone tried or modifier this version?
Thanks

Hi AlePhotos
If you haven't found it already: TPA3116D2 Amp

Cheers - J

 

[farhad]

View attachment 855599
farhad-San,
If you feel too sensitive to detect the short term supply voltage drop, you can modify the circuit like this way...

Dear CyberPit, Thank you so much for your suggestion. I will check the new circuit and report here.