NEC company has introduced a new generation of audio driver Ic-PPC1342V in order to adapt to the high power requirements after the broadband low distortion 50w driving circuit rVPC1225H. The lc has the advantages of t1PC1225H and the same peripheral circuits. The voltage deviation is smaller (±5mV), the voltage adaptation range is wider (20~±70V), and the driving power is more abundant, which is the first choice for the home-made amplifier. The lC port uses two rrPC1342v to form a 2×110W power amplifier circuit structure as shown in Figure 6-13 (the protection circuit in the dotted line is shared by two channels) Figure 6-14 shows the power amplifier printed circuit board except the protection circuit. Figure. In Figure 6-13, ICl (.uPCl342V) power supply is 65V, power amplifier tube (C2922, A1216) power supply ±56V t protection circuit and DC servo loop power supply are ±25V and ±15v respectively, using this front and rear high and low voltage, each The stage separation power supply mode plays a decisive role in reducing interstage interference and improving the dynamic range and sound quality of the power amplifier. The Icl internal circuit is mirrored symmetrically complementary differential amplifier preamplifier, power driven and perfect constant current and constant voltage by excellent DC amplifier. Start-up, protection, temperature compensation and other circuit components lcl3 foot and external cz complete the front-stage squelch function, VT1, R3. RP is ici external bias circuit, C4 is the vibration-absorbing capacitor, ensuring that IC1 does not appear high-frequency self-excitation Under the premise, it should be as small as possible. The IC2 and the external circuit form a shunting servo loop, which can control the output midpoint offset voltage within ±2mV, so that the amplifier is DCized, the power amplifier resolution is improved, the high frequency phase shift distortion is reduced, and the work is more stable. SUNLUX IOT Technology (Guangdong) INC. , https://www.sunluxbarcodereader.com