SI4420-D1-FT Datasheet, PDF (1/33 Pages) List of Unclassifed Manufacturers – Si4420 Universal ISM Band FSK Transceiver

Si4420 Universal ISM
Band FSK Transceiver
DESCRIPTION
Silicon Labs’ Si4420 is a single chip, low power, multi-channel FSK
transceiver designed for use in applications requiring FCC or ETSI
conformance for unlicensed use in the 315, 433, 868 and 915 MHz
bands. The Si4420 transceiver is a part of Silicon Labs’ EZRadio^TM product
line, which produces a flexible, low cost, and highly integrated solution that
does not require production alignments. The chip is a complete analog RF
and baseband transceiver including a multi-band PLL synthesizer with PA,
LNA, I/Q down converter mixers, baseband filters and amplifiers, and an
I/Q demodulator. All required RF functions are integrated. Only an external
crystal and bypass filtering are needed for operation.
The Si4420 features a completely integrated PLL for easy RF design, and
its rapid settling time allows for fast frequency-hopping, bypassing
multipath fading and interference to achieve robust wireless links. The
PLL’s high resolution allows the usage of multiple channels in any of the
bands. The receiver baseband bandwidth (BW) is programmable to
accommodate various deviation, data rate and crystal tolerance
requirements. The transceiver employs the Zero-IF approach with I/Q
demodulation. Consequently, no external components (except crystal and
decoupling) are needed in most applications.
The Si4420 dramatically reduces the load on the microcontroller with the
integrated digital data processing features: data filtering, clock recovery,
data pattern recognition, integrated FIFO and TX data register. The
automatic frequency control (AFC) feature allows the use of a low accuracy
(low cost) crystal. To minimize the system cost, the Si4420 can provide a
clock signal for the microcontroller, avoiding the need for two crystals.
For low power applications, the Si4420 supports low duty cycle operation
based on the internal wake-up timer.
FUNCTIONAL BLOCK DIAGRAM
RF1 13
RF2 12
LNA
PA
MIX
I
AMP OC
MIX
Q
Self cal.
AMP OC
RF Parts
PLL & I/Q VCO
with cal.
RSSI
BB Amp/Filt./Limiter
I/Q
DEMOD
COMP
DQD
AFC
clk
Data Filt
CLK Rec ^data
FIFO
7
DCLK /
CFIL /
FFIT /
FSK /
6 _{DATA /}
nFFS
Data processing units
CLK div
8
CLK
Xosc
9
XTL /
REF
WTM
with cal.
LBD
Low Power parts
Controller
Bias
15 1
ARSSI SDI
2
3
4
5
10
16
SCK nSEL SDO nIRQ nRES nINT /
VDI
11 14
VSS VDD
Si4420
PIN ASSIGNMENT
Rev C and later
This document refers to Si4420-IC Rev D1.
See www.silabs.com/integration for any applicable
errata. See back page for ordering information.
FEATURES
 Fully integrated (low BOM, easy design-in)
 No alignment required in production
 Fast-settling, programmable, high-resolution PLL synthesizer
 Fast frequency-hopping capability
 High bit rate (up to 115.2 kbps in digital mode and 256 kbps
in analog mode)
 Direct differential antenna input/output
 Integrated power amplifier
 Programmable TX frequency deviation (15 to 240 KHz)
 Programmable RX baseband bandwidth (67 to 400 kHz)
 Analog and digital RSSI outputs
 Automatic frequency control (AFC)
 Data quality detection (DQD)
 Internal data filtering and clock recovery
 RX synchron pattern recognition
 SPI compatible serial control interface
 Clock and reset signals for microcontroller
 16 bit RX Data FIFO
 Two 8 bit TX data registers
 Low power duty cycle mode
 Standard 10 MHz crystal reference
 Wake-up timer
 2.2 to 5.4 V supply voltage
 Low power consumption
 Low standby current (0.3 A)
 Compact 16 pin TSSOP package
TYPICAL APPLICATIONS
 Remote control
 Home security and alarm
 Wireless keyboard/mouse and other PC peripherals
 Toy controls
 Remote keyless entry
 Tire pressure monitoring
 Telemetry
 Remote automatic meter reading
Si4420-DS Rev 1.7r 0308
1
www.silabs.com