Sanyo LED-24XR113D, Service Manual

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TUNER IC XC5200C
The Single-Chip Multi-Standard Tuner XC5200C supports all analog TV formats transmitted
worldwide in the 42-1000 MHz band on either cable or terrestrial broadcast channels. It implements
on-chip tuning, and channel filtering without external (SAW) filters and has no manually tunable parts.
The broadband tuner converts the selected channel into an Intermediate Frequency (IF), which is
thensampled by an internal high-resolution analog-to-digital converter (A/D) for further processing.
The IF signals are filtered using a standard-dependent high-rejection channel filter and converted to a
userprogrammable output frequency. At the output of the D/A converter, the TV signal is low-pass filtered
using a high-performance smoothing filter and input to a variable gain amplifier. The IF output amplifier
gain can be controlled via an external analog signal on Vagc.
The XC5200C architecture is summarized in Figure 1. XC5200C Block Diagram.