U4454B

www.DataSheet4U.com U4454B Quasi-Split-Sound Processing and AM-Demodulator Description The U4454B quasi-split-sound processor is a bipolar integrated circuit for all FM-TV standards and NICAM sound systems. For FM/NICAM the IC operates as QSS-mixer. In case of AM sound the circuit can be used as AM demodulator. Features D PLL intercarrier-mixer for all FM standards (incl. NICAM sound system) D High grade signal processing for FM/NICAM sound systems D Also suitable as AM-demodulator D Gain controlled wideband amplifier D AGC operates as a peak- and mean-level detector D High input sensitivity D Wide supply voltage range (6.8 V up to 13 V) D Low power consumption D ESD protection Case: 16-pin DIL plastic Block Diagram VCO Tank Loop filter 93 7653 12 Lock detector 16 IF Input 1 Video 11 8 9 VCO 90° 0° Interference rejection 6 Output Overload detector 14 3 NC +/– Lock detector AGC +V S 2 NC 5 IF AGC 4 15 10 7 Average 13 Figure 1. TELEFUNKEN Semiconductors Rev. A1, 23-Feb-96 1 (7) Preliminary Information U4454B Pin Description IFin NC NC GND C5 Vout C7 1 2 3 4 5 6 7 16 IFin 15 GND 14 VS 13 CRef 12 LF 11 LF 10 GND 9 95 11256 Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Symbol IFin NC NC GND C5 Vout C7 VVCO VVCO GND LF LD CRef VS GND IFin Function IF input Not connected Not connected Ground IF-AGC time constant Output for AM (audio frequency) or FM (intercarrier frequency) Averaging value (IF-AGC function) VCO circuit VCO circuit Ground PLL loop filter PLL...