
Temic Semiconductors
Description
The TDA4474 is an integrated bipolar circuit for full multistandard video/sound IF (VIF/SIF) signal processing in TV/VCR and Multimedia applications. The circuit processes all TV video IF signals with negative modulation (e.g. B/G standard), positive modulation (e.g. L standard) and the AM, FM/NICAM sound IF signals. Four IF inputs (2 x VIF plus 2 x SIF) and the common pinning with TDA4471 gives flexibility to design a universal IF module for various applications.
FEATUREs
● 5V supply voltage; low power consumption
● Active carrier generation by FPLL principle (frequency–phase–locked–loop) for true synchronous demodulation
● Very linear video demodulation, good pulse response and excellent intermodulation figures
● VCO circuit is operating on picture carrier frequency, the VCO frequency is switchable for the L’ mode
● Alignment–free AFC without external reference circuit, polarity of the AFC curve is switchable
● VIF–AGC for negative modulated signals (peak sync detection) and for positive modulation (peak white/black level detector)
● Tuner AGC with adjustable take over point
● Alignment–free quasi parallel sound (QPS) mixer for FM/NICAM sound IF signals
● Intercarrier output signal is gain controlled (necessary for digital sound processing)
● Complete alignment–free AM demodulator with gain controlled AF output
● Separate SIF–AGC with average detection
● Parallel operation of the AM demodulator and QPS mixer (for NICAM–L stereo sound)
● Four IF inputs (2 x VIFin and 2 x SIFin)
● Package and relevant pinning is compatible with the TDA4471; simplifies the design of an universal IF module