
Analog Devices
GENERAL DESCRIPTION
The AD1970 is a complete analog or digital-in, analog-out BTSC encoder which includes pilot-tone generation and subcarrier mixing functions. The stereo ADC provides the means for digitization of the analog baseband audio signal. A built-in high performance DAC is provided to output the BTSC baseband composite signal. The output of the AD1970 can be connected with minimal external circuitry to the input of a 4.5 MHz aural FM modulator.
FEATURES
Complete BTSC encoder
Pilot tone generator
Includes subcarrier modulation
Channel separation: 30 dB
Bandwidth up to 14 kHz
Stereo analog or digital input
Phat-Stereo™ algorithm for stereo image enhancement
Dialog enhancement function for playing wide dynamic
range video sources over built-in TV speakers
Includes L − R dual-band compressor
I2C port for control of modes, effects, and parameters
Analog input performance
74 dB dynamic range
−72 dB THD + N
Digital input performance
87 dB dynamic range
−83 dB THD + N
Integrated op amps for analog inputs and outputs
Single-ended output reduces external part count
Integrated PLL generates all clocks from composite video,
48 kHz sample clock, or high speed master clock
Sync stripper to recover video clock from composite
video signal
Output level control for setting aural carrier deviation
Macrovision™-compliant
Dolby™ RF mode-compatible
48-pin LQFP plastic package
APPLICATIONS
Digital set top box
DVD player
DVD recorder