深圳市华之电科技有限公司

MC44BS373CADR2

MC44BS373CADR2

MC44BS373CADR2

Features Features

1 Features

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.

The MC44BS373CA also has the following features:

• Integrated on-chip programmable UHF oscillator

• No external varicaps diodes/inductor or tuned components

• Extremely low external component count

• Channel 21–69 UHF operation

• VHF range possible by internal dividers (30–450 MHz)

• Boosted TVOUT level (82 dBμV typical)

• High-speed read and write I2C bus compatible (800 kHz)

• I2C address selectable by pin (four choices) using external resistor (available only in QFN20

package)

• I2C bus 5- and 3.3-V compatible

• Fixed video modulation depth (93% typical in system L and 82% typical in the other standards)

• Peak white clip disabled by bus

• Programmable picture/sound carrier ratio (12 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 and 62.5 kHz)

• Direct RF sound modulator input (FM and AM modulator bypassed) for NICAM or stereo sound

MC44BS373CADR2