VIDEO, CHROMA AND SYNCHRONIZING SIGNALS PROCESSING IC FOR PAL / NTSC / SECAM SYSTEM COLOR TV

TB1227CNG that is a signal processing IC for the PAL / NTSC / SECAM color TV system integrates video, chroma and synchronizing signal processing circuits together in a 56-pin shrink DIP plastic package. TB1227CNG incorporates a high performance picture quality compensation circuit in the video section, an automatic PAL / NTSC / SECAM discrimination circuit in the chroma section, and an automatic 50 / 60Hz discrimination circuit in the synchronizing section. Besides a crystal oscillator that internally generates 4.43MHz, 3.58MHz and M / N-PAL clock signals for color demodulation, there is a horizontal PLL circuit built in the IC.

The PAL / SECAM demodulation circuit which is an adjustment-free circuit incorporates a 1H DL circuit inside for operating the base band signal processing system.

Also, TB1227CNG makes it possible to set or control various functions through the built-in I2C bus line.

FEATURES

Video section

? Built-in trap filter

? Black expansion circuit

? Variable DC regeneration rate

? Y delay line

? Sharpness control by aperture control

? γ correction

? VSM output

Chroma section

? Built-in 1H Delay circuit

? PAL / SECAM base band demodulation system

? One crystal color demodulation circuit

(4.43MHz, 3.58MHz, M / N-PAL)

? Automatic system discrimination, system forced mode

? 1H delay line also serves as comb filter in NTSC demodulation

? Built-in band-pass filter, SECAM bell filter

? Color limiter circuit

? Fsc output

Synchronizing deflecting section

? Built-in horizontal VCO resonator

? Adjustment-free horizontal / vertical oscillation by count-down circuit

? Double AFC circuit

? Vertical frequency automatic discrimination circuit

? Horizontal / vertical holding adjustment

? Vertical ramp output

? Vertical amplitude adjustment

? Vertical linearity / S-shaped curve adjustment

? SCP (Sand Castle Pulse) output

Text section

? Linear RGB input

? OSD RGB input

? Cut / off-drive adjustment

? RGB primary signal output