SI4822-A10 Datasheet, PDF (13/24 Pages) Silicon Laboratories – BROADCAST ANALOG TUNING DIGITAL DISPLAY AM/FM/SW RADIO RECEIVER

4. Functional Description
Si4822/26-A10
AMI
AM
ANT
RFGND
FM
ANT
FMI
XTALI
2.0~3.6V _VDD1/2
LNA
AGC
0/90
AFC
REG
XTAL
OSC
Si4^S8ⁱ⁴3⁸0²/²3^/4²⁶
ADC
DSP
DAC
ADC
AOUT
ADC
CONTROL INTERFACE
TUNE1/2
BAND
Figure 4. Si4822/26-A10 Functional Block Diagram
4.1. Overview
The Si4822/26-A10 is the entry level 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, Si4822/26 can output the
AM/FM/SW frequencies and band and volume
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 Si4822/26 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
Si4822/26 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,
Si4822/26 offers unmatched integration and PCB space
savings with minimum external components and a 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 Si4822/26 provides good flexibility in using the
chip. The frequency range of FM/AM/SW bands, de-
emphasis value, AM tuning step, and AM soft mute
level/rate 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 provided by
either the crystal or by the host MCU within tolerance.
The Si4822/26 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