TDA8060TS Datasheet, PDF (10/16 Pages) NXP Semiconductors – Satellite ZERO-IF QPSK down-converter

Philips Semiconductors
Satellite ZERO-IF QPSK down-converter
Product specification
TDA8060TS
APPLICATION INFORMATION
Close attention should be paid to the design of the external
tank circuit of the VCO so that it covers the
920 to 2200 MHz frequency range. Both series 6 Ω
resistors kill all parasitic oscillations that could alter this
frequency range. The BB835 Siemens varicap diodes are
mentioned because they provide the highest C_max/C_min
ratio as well as the least parasitic elements in our
frequency range. The U-shaped inductance can be printed
with a total length of approximately 20 mm.
Filters LP1 and LP2 are not detailed in this data sheet
because their design only depends on the global system.
As the TDA8060 has been designed to be compatible with
DVB, DSS and Asian DVB, the cut-off frequencies and the
tolerance in group delay, the orders of the filters cannot be
globally established.
Nevertheless, TDA8060 internally filters the baseband at
100 MHz and the nominal levels at inputs and outputs
mentioned in the specification table should be respected.
The input impedance of LP1 and LP2 must exceed 400 Ω
to avoid signal distortion.
The converter outputs (pin IOUT and pin QOUT) must be
AC-coupled via the low-pass filter to the baseband
amplifiers inputs (pin IBBIN and pin QBBIN). Because of
the high impedance at pin IQBBIN, a 100 nF capacitor
gives a high-pass frequency of 160 Hz.
1999 Aug 30
10