(ARCHIVED)
The MC44BS373CA is a multi-standard, PAL/SECAM/NTSC modulator.
The channel is set by an on-chip high-speed I2C compatible bus receiver. A phase-locked loop (PLL) tunes the modulator over the full UHF range.
The modulator incorporates a sound subcarrier oscillator and uses a second PLL to derive 4.5, 5.5, 6.0, and 6.5 MHz subcarrier frequencies. These frequencies are selectable by bus.
The modulation standard can be chosen using a control bit that selects between positive and negative modulation.
The picture-to-sound ratio may be adjusted using the bus. In addition, an on-chip video test pattern generator can be switched ON with a 1 KHz audio test signal.
View Block DiagramFeatures
- Integrated on-chip programmable UHF oscillator
- No external varicaps diodes/inductor or tuned components
- Extremely low external components count
- Channel 21-69 UHF operation
- VHF range possible by internal dividers (30 MHz to 450 MHz)
- Boosted TVout level (82 dBuV typical)
- High-speed read and write I2C-bus compatible (800 kHz)
- I2C address selectable by pin (4 choices); available only in QFN20 pin package
- I2C-bus 5 V and 3.3 V compatible
- Fixed video modulation depth (93% typ. in system L and 82% typ. in the other standards)
- Peak White Clip disabled by bus
- Programmable picture/sound carrier ratio (12 dB and 16 dB)
- Integrated on-chip programmable sound subcarrier oscillator (4.5, 5.5, 6.0 and 6.5 MHz) - no external varicaps
- Programmable sound reference frequency (31.25 kHz and 62.5 kHz)
- Direct RF sound modulator input (FM and AM modulator bypassed for NICAM or stereo sound applications); available only in QFN20 pin package
- On-chip video test pattern generator with sound test signal (1 kHz)
- Low-power programmable modulator standby mode
- Transient output inhibit during PLL lock-up at power-on
- Logical output port controlled by bus
- ESD protection, minimum 4 kV
Increase Your Knowledge
- Design News Update Subscribe for design tips, tricks and product news delivered to your inbox.
- On-Demand Training Learn from the experts at your convenience.
