GENERAL DESCRIPTION

The SAF7129AH encodes digital CB-Y-CR video data to an NTSC, PAL or SECAM CVBS or S-video signal. Simultaneously, RGB or bypassed but interpolated CB-Y-CR signals are available via three additional DACs.

Through a 54 MHz multiplexed digital D1 input port, the circuit accepts two ITU-R BT.656 compatible CB-Y-CR data streams with 720 active pixels per line in 4 : 2 : 2 multiplexed formats. For example, an MPEG decoded data with overlay and MPEG decoded data without overlay, where one data stream is latched at the rising, the other one is latched at the falling clock edge.

It includes a sync/clock generator and on-chip DACs.

FEATURES

• Monolithic CMOS 3.3 V device, 5 V I2C-bus optional

• Digital PAL/NTSC/SECAM encoder

• System pixel frequency 13.5 MHz

• 54 MHz double-speed multiplexed D1 interface capable of splitting data into two separate channels (encoded and baseband)

• Three Digital-to-Analog Converters (DACs) for CVBS (CSYNC), VBS (CVBS) and C (CVBS) two times oversampled with 10-bit resolution (signals in brackets optional)

• Three DACs for RED (CR), GREEN (Y) and BLUE (CB) two times oversampled with 9-bit resolution (signals in brackets optional)

• Alternatively, an advanced composite sync is available on the CVBS output for RGB display centreing

• Real-time control of subcarrier

• Cross-colour reduction filter

• Closed captioning encoding and World Standard Teletext (WST) and North-American Broadcast Text System (NABTS) teletext encoding including sequencer and filter

• Copy Generation Management System (CGMS) encoding (CGMS described by standard CPR-1204 of EIAJ); 20 bits in lines 20/283 (NTSC) can be loaded via I2C-bus

• Fast I2C-bus control port (400 kHz)

• Line 23 Wide Screen Signalling (WSS) encoding

• Video Programming System (VPS) data encoding in line 16 (50/625 lines counting)

• Encoder can be master or slave

• Programmable horizontal and vertical input synchronization phase

• Programmable horizontal sync output phase

• Internal Colour Bar Generator (CBG)

• Controlled rise/fall times of output syncs and blanking

• On-chip crystal oscillator (3rd-harmonic or fundamental crystal)

• Down mode (low output voltage) or power-save mode of DACs

• QFP44 package.