Silicon Laboratories SI4734/35-B20 - Manual (Page 19)

S i 4 7 3 4 / 3 5 - B 2 0
Rev. 1.0 19
4. Functional Description
4.1. Overview
Figure 9. Functional Block Diagram
The Si4734/35 is the industry's first fully integrated,
100% CMOS AM/FM/SW/LW radio receiver IC. Offering
unmatched integration and PCB space savings, the
Si4734/35 requires minimal external components and
less than 20 mm
2
of board area, excluding the antenna
inputs. The Si4734/35 AM/FM/SW/LW radio provides
the space savings and low power consumption
necessary for portable devices while delivering the high
performance and design simplicity desired for all
AM/FM/SW/LW solutions.
Leveraging Silicon Laboratories' proven and patented
Si4700/01 FM tuner's digital low intermediate frequency
(low-IF) receiver architecture, the Si4734/35 delivers
superior RF performance and interference rejection in
AM, FM, and short wave and long wave bands. The
high integration and complete system production test
simplifies design-in, increases system quality, and
improves manufacturability.
The Si4734/35 is a feature-rich solution including
advanced seek algorithms, soft mute, auto-calibrated
digital tuning, and FM stereo processing. In addition, the
Si4734/35 provides analog or digital audio output and a
programmable reference clock. The device supports
I
2
C-compatible 2-wire control interface, SPI, and a
Si4700/01 backwards-compatible 3-wire control
interface.
The Si4734/35 utilizes digital processing to achieve high
fidelity, optimal performance, and design flexibility. The
chip provides excellent pilot rejection, selectivity, and
unmatched audio performance, and offers both the
manufacturer and the end-user extensive
programmability and flexibility in the listening
experience.
The Si4735 incorporates a digital processor for the
European Radio Data System (RDS) and the North
American Radio Broadcast Data System (RBDS),
including all required symbol decoding, block
synchronization, error detection, and error correction
functions. Using RDS, the Si4735 enables broadcast
data such as station identification and song name to be
displayed to the user.
ADC
ADC
Si4734/35
DSP
DAC
DAC
FMI
FM / SW
ANT
VIO
1.5-3.6V
SCLK
SDIO
CONTROL
INTERFACE
SEN RST
ROUT
LOUT
LDO
VDD
GND
2.7 - 5.5 V
RDS
(Si4735)
AM / LW
ANT
RFGND
AMI
LNA
LNA
LOW-IF
DIGITAL
AUDIO
(Si4735)
DOUT
DFS
GPO/DCLK
AGC
AGC
AFC
RCLK