Details about TDA 7293 Op Amp performance not currently covered by the datasheet

[Brian_DMC]

We are implementing two TDA 7293 amplifiers in a Master / slave configuration, for a 35 watt, 30 kHz drive of a high frequency device that operates between 2.8 ohms and 7.1 ohms on the output pins (5.6 ohms to 14.2 ohms per amplifier). We have a couple of questions we want to get clarified:

1. What is the output voltage range of the device, as a function of input source voltage? Nothing is specified in Table 2.1, but the onset power points of significant THD on the plots in figures 14 and 15 suggest that clipping and distortion start for peak to peak output amplitudes that exceed 80% to 85% of the supply voltage range. Is that correct?
2. Is there a Gain Bandwidth product specification for the TDA7293 device? If so, what is it? Table 2.3 lists an open loop voltage gain, and specifies a closed loop voltage gain (without specifying the frequency), but no GBWP listing.
3. Note (2) of the Gv entry in table 2.3 states:  “Gvmin >/= 26dB”. Some people in the group here believe that means the minimum gain in any application MUST be be more than 26db; others believe it just refers to the test conditions. Can the gain be lower – for instance, 20 dB? Seems like it should not matter for lower gains.

[AScha.3]

1. This is an audio power amp , so its output goes close to +/- supply .

2. no. 

3. 26dB is minimum gain for stability; so your circuit should use 26dB or more.

At lower gain setting oscillation might start.

[MasterT]

Q.2:

You can calculate high freq. limits via slew rate introduced distortion.

F = S-R / 2*PI()* Vp-p = 10 V/usec  / 6.28 * 80 Vp-p = 20 kHz

Or setting Freq = 30 kHz, max output non-distorted voltage = 53 Vp-p