SI4840-A10 Datasheet, PDF (13/26 Pages) Silicon Laboratories – BROADCAST ANALOG TUNING DIGITAL DISPLAY AM/FM/SW RADIO RECEIVER

4. Functional Description
AM
ANT
FM
ANT
AMI
RFGND
FMI
LNA
AGC
0/90
XTALI
2.0~3.6V _VDD1/2
AFC
REG
XTAL
OSC
Si4840/44-A10
Si4^S8ⁱ⁴3⁸0⁴/^x34
ADC
DAC
LOUT
DSP
ADC
DAC
ROUT
TUNE1/2
ADC
CONTROL INTERFACE
BAND
Figure 4. Si4840/44-A10 Functional Block Diagram
4.1. Overview
The Si4840/44-A10 is the first analog-tuned digital-
display digital CMOS AM/FM/SW radio receiver IC that
integrates the complete receiver function from antenna
input to audio output. Working with an external MCU
with LCD/LED driver, Si4840/44-A10 can output the
AM/FM/SW frequencies, band, Bass/Treble and
stereo/mono information to display on LCD/LED, while
using a simple potentiometer at the front end for analog-
tune. Leveraging Silicon Laboratories' proven and
patented digital low intermediate frequency (low-IF)
receiver architecture, the Si4840/44 delivers superior
RF performance and interference rejection in AM, FM
and SW bands. Additionally, the digital core provides
advanced audio conditioning for all environments,
removing pops, clicks, and loud static in variable signal
conditions. The superior control algorithm integrated in
Si4840/44-A10 provides easy and reliable control
interface while eliminating all the manual tuned external
components used in traditional solutions.
Like other successful audio products from Silicon Labs,
Si4840/44-A10 offers unmatched integration and PCB
space savings with minimum external components and
small board area on a single side PCB. The high
integration and complete system production test
simplifies design-in, increases system quality, and
improves manufacturability. The receiver has very low
power consumption, runs off two AAA batteries, and
delivers the performance benefits of high performance
digital radio experience with digital display to the legacy
analog-tuned radio market.
The Si4840/44-A10 provides good flexibility in using the
chip. The frequency range of FM/AM/SW bands,
mono/stereo threshold, de-emphasis value, AM tuning
step, AM soft mute level/rate, and Bass/Treble can be
either configured by the MCU or by using external
hardware to make a selection. The reference clock of
the FM tuner can be either provided by the crystal, or by
the host MCU within tolerance.
Si4840/44-A10 also has flexibility in selecting bands
and configuring band properties, enabling masked Host
MCU for multiple projects, and reducing the cost of
development. Four tuning preferences are available to
meet different tuning preference requirements.
Rev.1.0
13