L64780 LSI Logic Corporation, L64780 Datasheet - Page 14

• Manufacturer Part Number: L64780
• Description: Dvb-t Cofdm Demodulator Technical Manual 2/00
• Manufacturer: LSI Logic Corporation

1.3 RF Tuner Block Functions
Figure 1.2
1-4
RF Filter
Tracking
UHF Tuner Example
which then completes the error correction, delivering an MPEG-2
Transport Stream. Other MPEG-standard LSI Logic chips (for example,
L64118 and L64005) can then be used to demultiplex the MPEG-2
Transport Stream into its coded audio, coded video, and data
components, handle Conditional Access, and decode the audio and
video signals for presentation to the display and loudspeakers. In
Figure
RF-channel selection, mode selection for the L64780 chip, and program
selection for the MPEG demultiplexer.
Figure 1.2
The example uses a double-conversion approach, in which the RF Tuner
converts the UHF signal to a first IF (IF1, where filtering, amplification,
and gain control are done) followed by another conversion to the second
low IF, (IF2), required at the input of the L64780.
Introduction
1.1, the microprocessor is embedded in the L64118. It controls
LO 1
indicates the functions performed within the RF Tuner block.
Filter
IF 1
LO 2
Filter
IF 2
L64780