TDA4556

· Gain controlled chrominance amplifier for PAL, SECAM and NTSC
· ACC rectifier circuits (PAL/NTSC, SECAM)
· Burst blanking (PAL) in front of 64 ms glass delay line
· Chrominance output stage for driving the 64 ms glass delay line (PAL, SECAM)
· Limiter stages for direct and delayed SECAM signal
· SECAM permutator Demodulator part
· Flyback blanking incorporated in the two synchronous demodulators (PAL, NTSC)
· PAL switch
· Internal PAL matrix
· Two quadrature demodulators with external reference tuned circuits (SECAM)
· Internal filtering of residual carrier
· De-emphasis (SECAM)
· Insertion of reference voltages as achromatic value (SECAM) in the (B-Y) and (R-Y) colour difference output stages (blanking) Identification part
· Automatic standard recognition by sequential inquiry
· Delay for colour-on and scanning-on
· Reliable SECAM identification by PAL priority circuit
· Forced switch-on of a standard
· Four switching voltages for chrominance filters, traps and crystals
· Two identification circuits for PAL/SECAM (H/2) and NTSC
· PAL/SECAM flip-flop
· SECAM identification mode switch (horizontal, vertical or combined horizontal and vertical)
· Crystal oscillator with divider stages and PLL circuitry (PAL, NTSC) for double colour subcarrier frequency
· HUE control (NTSC)
· Service switch

The TDA4555 and TDA4556 are monolithic integrated multistandard colour decoders for the PAL, SECAM, NTSC 3,58 MHz and NTSC 4,43 MHz standards. The difference between the TDA4555 and TDA4556 is the polarity of the colour difference output signals (B-Y) and (R-Y).