zl10354 Zarlink Semiconductor, zl10354 Datasheet - Page 16

• Manufacturer Part Number: zl10354
• Description: Diversity Enabled Nordig Unified Dvb-t Cofdm Terrestrial Demodulator For Pc-tv And Hand-held Digital Tv Dtv
• Manufacturer: Zarlink Semiconductor

ZL10354
Data Sheet
3.0
Diversity Operation of ZL10354
The ZL10354 demodulator can be used as a stand-alone system, but is designed primarily for use as part of a
multi-receiver system in which two or more tuners, each with their own aerial, are connected to the same number of
ZL10354s. This is shown in general form in Figure 5.
Figure 5 - Outline Diversity System
The ZL10354s are connected together in a chain using the diversity data bus, a high-speed, 5-bit bus which feeds
channel-corrected, ODFM data to the next demodulator in the chain. Each subsequent ZL10354 combines the
incoming OFDM data with its own received data to get the optimum reception for each carrier.
The SADD1 and SADD0 pins allow up to four ZL10354s to each be defined with a different serial bus address, but
the system is not limited to four devices. However, each group of (up to) four ZL10354s must be controlled via a
separate serial bus to avoid address clashes. The other main requirement is that all the demodulators are driven
from the same clock source.
The diversity data are transferred from one device to the next through either the diversity pins, or parts of the MPEG
bus, which isn’t (usually) required on any device other than the last. The diversity bus pins are very flexible, being
definable as either inputs or outputs, and when defined as inputs, the data pin order can be swapped. This flexibility
eases the PCB layout issues considerably. In effect, six different pinouts can be defined for the ZL10354, in addition
to the default non-diversity pinout. These pinout possibilities are shown in detail in Table 6, the non-diversity pin list
is in Table 5, and the two main diversity pin list options are in Table 3 and Table 4. In these latter two tables the bus
pin swap options are not shown.
The versatility of this approach can be demonstrated with a dual receiver system (see Figure 6) in which the two
ZL10354 based receivers can function either as a single diversity receiver, giving improved reception in mobile
environments, or as a dual non-diversity receiver where two MPEG streams from different channels are required for
picture-in-picture or play-and-record applications.
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Zarlink Semiconductor Inc.