Sanyo LED-46XR123D, Service Manual

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IC Block Diagram
1
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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 then sampled 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 user programmable 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.