Description:
...Circuit DescriptionThis integrated circuit permits the design of TV-tuners covering the entire frequency range from48 … 900 MHz split into 3 frequency bands. The application is suitable for all tuners in TV- andVCR-sets.... ...unbalanced oscillator for VHF I and two balanced oscillators for VHF II and UHF, a SAW-filter driveramplifier as well as a reference voltage source and a band switch. Filters between tuner input andIC separate the TV-frequency signal into three bands. The band switch ensures that only one bandat a time is activated. In the activated band the signal passes a frontend stage with MOSFET-... ...is a high-impedance stage for the VHF I-range and a low-impedance stage for the VHF II- and UHF-range, respectively. The input signal is mixed there with the oscillator signal from the activatedoscillator section and fed into common IF-stage for all bands. The IF-signal is further amplified in aSAW-filter driver section in order to drive the SAW-filter with a low impedance....