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TDA7350A

tors. Basically, the connection shown in fig. 34 has been chosen. First of all because its voltage swing is

Ω each. Then,

the gain VOUT/VIN is greater than unity, approximately 1+R2/R1. (VCC/2 is fixed by an auxiliary amplifier

common to both channel). It is possible, controlling the amount of this local feedback, to force the loop

gain (A .

β) to less than unity at frequencies for which the phase shift is 180°. This means that the output

buffer is intrinsically stable and not prone to oscillation.

Figure 34. The New Output Stage

In contrast, with the circuit of fig. 35, the solution adopted to reduce the gain at high frequencies is the use

of an external RC network.

4.8 AMPLIFIER BLOCK DIAGRAM

The block diagram of each voltage amplifier is shown in fig. 36. Regardless of production spread, the cur-

rent in each final stage is kept low, with enough margin on the minimum, below which cross-over distortion

would appear.

Figure 35. A Classical Output Stage

Figure 36. Amplifier Block Diagram