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MC44BS374T1/374T1A Advance Information
Features
1 Features
The MC44BS374T1/374T1A is a PAL/NTSC Modulator with integrated VCO.
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 6.5MHz subcarrier frequencies. These frequencies are selectable by bus.
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 1KHz audio test signal.
The MC44BS374T1/374T1A have the following features:
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 (30MHz-450MHz)
Boosted TV output level (82 dBuV typical) for the MC44BS374T1A
TV output level of 75 dBuV typical for the MC44BS374T1
High speed read and write I2C-bus compatible (800kHz)
I2C-bus 5V and 3.3V compatible
Fixed video modulation depth (82% typical)
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
On-chip video test pattern generator with sound test signal (1kHz)
Low-power programmable modulator standby mode
Transient output inhibit during PLL Lock-up at power-ON
Logical Output Port controlled by bus
Start-up on channel ‘71’ (871.25 MHz)
ESD protection, minimum 4 kV
2 Comparing the MC44BS374T1 and MC44BS374T1A to the
MC44BC374T1
Compared to the MC44BC374T1 devices, the MC44BS374T1/374T1A has the following improvements:
Higher output level for the MC44BS374T1A (82 dBuV versus 74.5 dBuV)
Higher Video signal to noise (+ 3 dB) for the MC44BS374T1A
I2C-bus 3.3V compatible
Lower power consumption in normal and standby modes (-2 mA)
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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