SI4735-D60-GU Silicon Laboratories Inc, SI4735-D60-GU Datasheet - Page 23

• Manufacturer Part Number: SI4735-D60-GU
• Description: RF RX FM AM SW LW 24 SSOP
• Manufacturer: Silicon Laboratories Inc
• Series: -r

Specifications of SI4735-D60-GU

• Mfg Application Notes: SI47xx Prog Guide AppNote
• Frequency: 153kHz ~ 279kHz, 520kHz ~ 1.71MHz, 2.3MHz ~ 26.1MHz, 64MHz ~ 108MHz
• Sensitivity: -
• Data Rate - Maximum: -
• Modulation Or Protocol: AM, FM, SW-LW
• Applications: General Purpose
• Current - Receiving: 18.5mA
• Data Interface: PCB, Surface Mount
• Memory Size: -
• Antenna Connector: PCB, Surface Mount
• Features: RSSI Equipped
• Voltage - Supply: 2 V ~ 5.5 V
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 24-SSOP (0.154", 3.90mm Width)
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-2140

4.2. Operating Modes
The Si473x operates in either an FM receive, AM
receive, or audio AUXIN ADC mode. In FM mode, radio
signals are received on FMI and processed by the FM
front-end circuitry. In AM mode, radio signals are
received on AMI and processed by the AM front-end
circuitry. In audio AUXIN ADC mode, stereo audio
signals on LIN/RIN are sampled, converted to digital,
filtered, and decimated to 32, 44.1, or 48 kHz for the I
digital audio interface. In addition to the receiver mode,
there is a clocking mode to choose to clock the Si473x
from a reference clock or crystal. On the Si473x, there is
an audio output mode to choose between an analog
and/or digital audio output. In the analog audio output
mode, ROUT and LOUT are used for the audio output
pins. In the digital audio mode, DOUT, DFS, and DCLK
pins are used. Concurrent analog/digital audio output
mode is also available requiring all five pins.
4.3. FM Receiver
The Si473x FM receiver is based on the proven
Si4700/01 FM tuner. The receiver uses a digital low-IF
architecture
components and factory adjustments. The Si473x
integrates a low noise amplifier (LNA) supporting the
worldwide FM broadcast band (64 to 108 MHz). An
AGC circuit controls the gain of the LNA to optimize
sensitivity and rejection of strong interferers. An image-
reject mixer downconverts the RF signal to low-IF. The
quadrature mixer output is amplified, filtered, and
digitized
converters (ADCs). This advanced architecture allows
the
demodulation, and stereo audio processing to achieve
superior performance compared to traditional analog
architectures.
Si473x
with
allowing
to
high
perform
the
resolution
channel
elimination
analog-to-digital
selection,
of
external
FM
Rev. 1.0
2
S
4.4. AM Receiver
The highly-integrated Si473x supports worldwide AM
band reception from 520 to 1710 kHz using a digital
low-IF architecture with a minimum number of external
components and no manual alignment required. This
digital low-IF architecture allows for high-precision
filtering offering excellent selectivity and SNR with
minimum variation across the AM band. The DSP also
provides adjustable channel step sizes in 1 kHz
increments, AM demodulation, soft mute, seven
different channel bandwidth filters, and additional
features, such as a programmable automatic volume
control (AVC) maximum gain allowing users to adjust
the level of background noise.
Similar to the FM receiver, the integrated LNA and AGC
optimize sensitivity and rejection of strong interferers
allowing better reception of weak stations.
The Si473x provides highly-accurate digital AM tuning
without
flexibility, the receiver supports a wide range of ferrite
loop sticks from 180–450 µH. An air loop antenna is
supported by using a transformer to increase the
effective inductance from the air loop. Using a 1:5 turn
ratio inductor, the inductance is increased by 25 times
and easily supports all typical AM air loop antennas
which generally vary between 10 and 20 µH.
4.5. SW Receiver
The Si4734/35 is the first fully integrated IC to support
AM and FM, as well as short wave (SW) band reception
from 2.3 to 26.1 MHz fully covering the 120 meter to
11 meter bands. The Si4734/35 offers extensive
shortwave features such as continuous digital tuning
with minimal discrete components and no factory
adjustments. Other SW features include adjustable
channel step sizes in 1 kHz increments, adjustable
channel bandwidth settings, advanced seek algorithm,
and soft mute.
The Si4734/35 uses the FM antenna to capture short
wave signals. These signals are then fed directly into
the AMI pin in a wide band configuration. See "AN332:
Si47xx Programming Guide” and “AN383: Si47xx
Antenna and Schematic Guidelines" for more details.
Si4730/31/34/35-D60
factory
adjustments.
To
offer
maximum
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