Features

• Outputs to NTSC, PAL (B, D, G, H, I) and PAL-60
• 16-bit YCrCb (4:2:2) input format
• Simultaneous composite/S-video outputs
• Triple 9-bit video DACs
• 27 MHz DAC operating frequency eliminates the need for 1/sinc(x) correction filter
• Low-jitter phase-locked loop circuitry operates using a low-cost 14.31818 MHz crystal
• 40.5 or 33.9 MHz video decoder clock output
• 16.934 or 11.289 MHz audio decoder clock output
• 13.5 MHz and 27 MHz video pixel clock outputs
• Optimized luminance and chrominance internal filters for NTSC and PAL
• HSYNC* and VSYNC* outputs for master mode operation
• Sleep mode
• CMOS technology in 44-pin PLCC
• 5V single-supply operation

Description

The CH7203 video encoder integrates a dual PLL clock generator and a digital NTSC/PAL video encoder. By generating all essential clock signals for MPEG playback, and converting digital video inputs to either NTSC or PAL video signals, the CH7203 is an essential component of any low-cost solution for video-CD playback machines.

The CH7203 dual PLL clock synthesizer generates all clocks and timing signals from a 14.31818 MHz reference crystal (see application note 19 "Tuning Clock Outputs" for selection and tuning of the 14.31818 MHz crystal). The CH7203 generates a 40.5 or 33.9 MHz video decoder clock, 13.5 MHz and 27 MHz video pixel clocks, and a 16.934 or 11.289 MHz audio decoder clock. Timing signals from the PLLs are used to generate the horizontal and vertical sync signals which enable operating the CH7203 in master mode.

The fully digital video encoder is pin-programmable to generate either a 525-line NTSC or a 625-line PAL compatible video signal. It also features a logic selectable sleep mode which turns the encoder off while leaving both PLL's running.