MC44BC374T_ARCHIVED中文资料Multi-Standard Audio/Video Modulator数据手册恩XP规格书

描述 Description

Overview The MC44BC374T and MC44BC374T1 are phase-locked loop (PLL) tuned, ultra high frequency (UHF) and very high frequency (VHF), audio/video (A/V), high integration modulator, integrated circuits (IC). These devices are intended for use in VCRs, games, and set-top box systems, and both use \"T\" software.The MC44BC374T and MC44BC374T1 have the same hardware package as the MC44BC374C. The only difference is the software and the start up channel.The MC44BC374T starts up on channel 36 (591.25 MHz) and the MC44BC374T1 starts up on channel 71 (871.25 MHz). Both are compatible with the following formats:PAL—Phase Alternation Line (European TV format) NTSC—National Television System Committee An on-chip high-speed I2C compatible bus receiver sets the channel. It is tuned by a PLL over the full range of the UHF bands. 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, which are selectable using the bus.The modulation standard is chosen using a control bit that selects between System L and System B/G.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 MC44BC374T and MC44BC374T1 are available in a 16-pin (SO16NB) package.

特性 Features

•MC44BC374T available in channel 36 startup frequency (591.25 MHz)
•MC44BC374T1 available in channel 71 startup frequency (871.25 MHz)
•No external varicaps diodes/inductor or tuned components
•Channel 21-69 UHF operation
•VHF range possible by internal dividers (30 MHz to 450 MHz)
•Integrated on-chip programmable UHF oscillator
•Extremely low external components count
•High-speed read and write I2C-bus compatible (800 kHz)
•Fixed video modulation depth (80% in PAL and 90% in SECAM)
•Peak White Clip disabled via the bus
•Programmable picture/sound carrier ratio (12 dB and 16 dB)
•Integrated on-chip programmable sound subcarrier oscillator (4.5 MHz to 6.5 MHz)—no external varicaps
•On-chip video test pattern generator with sound test signal (1 kHz)
•Low-power programmable modulator standby mode programmable by I2C Bus or switchable by STBY pin voltage
•Transient output inhibit during PLL lock-up at power-on
•Custom masked versions with unique start-up settings possible (no I2C bus programming required)
•Extremely robust ESD protection, minimum 4 kV, typical 6 kV