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1.3 Main Features of Tuner
1.3.1 Dual band support
The tuner supports two different input paths – UHF and S-band. This essentially results
in dual band support:
a. UHF – From 470 to 862 MHz
b. S-band – From 2100 to 2700MHz
1.3.2 Fully integrated solution
The tuner integrates variable gain LNAs, PGAs, and has a built-in mixing and low pass
filtering. The tuner compensates internally for the DC offset, utilizing the DC correction
feedback which is generated by the demodulator.
In addition, the UHF path is single-ended, meaning that no Balance-Unbalance (Balun)
component is required for this path.
Further improvement of the performance is done by responding to the feed backs from
the tuner only during certain time slots windows as signaled by the demodulator.
1.3.3 Robust Clocking system
The tuner can be fed by two alternative clock sources:
a. External crystal at the range of 8 to 40MHz
b. Reference clock from the host system at the range of 4 to 40MHz (a 200mV p-p
minimum analog low voltage swing)
1.3.4 Robust power supply circuitry
The tuner is driven by input voltage of 1.2V.
The tuner has an on-chip LDOs and hence supports DC-DC supply without performance
degradation and provides PSRR of 80dB.
1.3.5 GSP controlled
The tuner is digitally controlled and configured using General Serial Port (I
2
C like), which
is driven by the demodulator. The control and configuration mechanism of the tuner can
be considered as an internal process of the SMS1180.
1.4 Main Features of
Demodulator
1.4.1 CMMB (S-TiMi) support
The demodulator is a dedicated CMMB (S-TiMi) component.
This chip CMMB functionality is enabled by loading the firmware to the demodulator.
Typically, the firmware image is stored on the host’s memory, and upon invocation of the
power-up sequence, the firmware image is loaded to the demodulator and initiates the
CMMB reception.
The firmware download duration depends on the physical interface used, and lasts
maximum 50msec (except for GSP where duration will extend for up to 1 second).
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