TPA3112D1 design information - ???

Raymond Frost

Does anyone understand how the PLIMIT voltage is used and the power output calculated together with the o/p voltage amplitude as per table 2 in the data sheet SLOS654C. I must be having an off day because I cannot find any useable data regarding this subject. Any derivation of the figures in the table would be helpful, I shall be using a 12V system target output power is 20W into 4 ohms.

So, I see one confusing entry in table 2 when comparing it to Figure 9 in datasheet, the 4th line of table 2, Vplimit should read 3.5V (approx) which is close to what I would guess at.

over 12 years ago

0 Don Dapkus over 12 years ago

TI__Guru**** 189401 points

Hi, Raymond,

This is discussed on pages 11 and 12 of that document under the title heading, "PLIMIT,"

-d2

0 Raymond Frost over 12 years ago

Prodigy 20 points

What is the relationship between the Plimit voltage and the output voltage amplitude(Vp-p) given in table 2 of the datasheet SLOS654C?

0 Don Dapkus over 12 years ago

TI__Guru**** 189401 points

Hi, Raymond,

I just answered your other post asking about this.

And, you probably don't even need to muck about with PLIMIT, as Figure 7 shows 4 ohms 12V will result in clipping at 20W anyway.

-d2

0 Raymond Frost over 12 years ago in reply to Don Dapkus

Prodigy 20 points

Figure 9 implies nearly 20W when Vplimit is 4.0 (figure 7 is harmonic distortion curves) and Figure 9 suggests I will need to set Vplimit just above 4V. I obviously do not understand this device after reading the datasheet, this means that the data sheet is not very clear or I need to read another document for greater understanding. My interpretation of Figure 7 is that I shall get a sudden increase in distortion when operating at just over 10W and up to 20W. Should I just connect Plimit to GVDD instead of setting to a particular voltage?

0 Don Dapkus over 12 years ago in reply to Raymond Frost

TI__Guru**** 189401 points

Raymond,

Yeah, the PLIMIT description in the d/s could be improved.

Like I said, though, you are basically running at what the device can do, so IMHO, you can ignore the PLIMIT, and yes, just tie it to GVDD and move on.

-d2

Audio

Audio forum

TPA3112D1 design information - ???