TUA2019-5X Datasheet, PDF (1/15 Pages) Siemens Semiconductor Group – VHF I / VHF II / UHF-Tuner IC

VHF I / VHF II / UHF-Tuner IC
TUA 2019-5X
Preliminary Data
Bipolar IC
Features
q Few external components
q Frequency and amplitude-stable unbalanced
oscillator for the VHF I-frequency range
q Frequency and amplitude-stable balanced oscillators
for the VHF II- and UHF-frequency range
q Optimum decoupling of input frequency from oscillator
q Double balanced mixer with wide dynamic range and
high-impedance inputs for the VHF I-frequency range
q Double balanced mixer with wide dynamic range and
low-impedance inputs for the VHF II- and
UHF-frequency range
q Low-impedance SAW-filter driver output
q SAW-filter driver with high signal-handling capability
q Internal band switch
q Low-noise, internal reference voltage
q Integrated 1st IF-bandpass filter
P-DSO-24-1
Type
TUA 2019-5X
TUA 2019-5X
Ordering Code
Q67000-A5150
Q67006-A5150
Package
P-DSO-24-1 (SMD)
P-DSO-24-1 Tape & Reel
Circuit Description
This integrated circuit permits the design of TV-tuners covering the entire frequency
range from 48 … 900 MHz split into 3 frequency bands. The application is suitable for all
tuners in TV- and VCR-sets.
The integrated circuit includes 3 balanced mixers (double balanced mixer/ring mixer),
one unbalanced oscillator for VHF I and two balanced oscillators for VHF II and UHF, a
SAW-filter driver amplifier as well as a reference voltage source and a band switch.
Filters between tuner input and IC separate the TV-frequency signal into three bands.
The band switch ensures that only one band at a time is activated. In the activated band
the signal passes a frontend stage with MOSFET-amplifier, a double-tuned bandpass
filter and is then fed to the balanced mixer input of the IC which 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 activated
oscillator section and fed into common IF-stage for all bands. The IF-signal is further
amplified in a SAW-filter driver section in order to drive the SAW-filter with a low
impedance.
Semiconductor Group
1
02.95