Application circuit of uPC1891

In the application circuit of ptPC1891A , SA is the working state conversion switch, with a total of four bits to choose from.
It is mainly realized by logically combining pins 11 and 12 of IC with different levels. Please refer to Table 5-12. Among them, H is
the high level Sv, L is the low level OVo potentiometer RPi is used to adjust the depth of the concert hall and cinema effects, RP2~
pin 4 is used to adjust the output intensity of the left and right channels and surround channels respectively, island~ c9 is an external filter capacitor. The power amplifier circuit part in the picture
is a surround channel power amplifier. The circuit uses TDA2030A to form a fffL form to increase the output power.
    The power supply voltage of PC1891A is 12V, and an integrated voltage regulator 7812,111 is used. The state control voltage of pin 2 is
Sv, which is controlled by 78 1 2 The output 12V voltage is provided after being stepped down by Rs and stabilized by VDi.