Internal circuit of TDA1521

Internal circuit schematic diagram of TDA1521.

TDA1521 is an excellent power amplifier integrated circuit launched by Philips. It has the characteristics of wide frequency response,
small transient intermodulation distortion, high conversion rate and high output power
    . TDA1521 includes TDA1521, TDA1521AT]~1521B, TDA1521AQ, T 】Both 1521BQ,
TDA1521Q and other models, their internal circuits and electrical parameters are basically the same, only the packaging form is different. This circuit adopts
9-pin single in-line package (TDA1521) and single-row zigzag package ( TDA1521 Q). The circuit is equipped with two identical
amplifiers and short circuit and overheat protection functions. It not only has high output power and low distortion, but also has good channel balance performance
. There is no impact noise when the power is turned on and there are few external components. The working power supply voltage range
    of this circuit is ±7.5~±20Vo. When Vc=±16V, the quiescent current IQ=
40mAo voltage gain Gv=30dBo harmonic distortion "∞- 0.15% (Po=6W)o output power per channel Po=
12W (RL=8fl, order still-o-5%) or 15W (RL= 8n, THD=10%). When single power supply vc=24V, the output power of
each channel is PO=6W (RL=蛐, order∞ - 10%) or 8W (RL= 8n,”∞=10%).