
2-5
PRISM 2.4GHz Chip Set
Direct Sequence Spread Spectrum
Wireless Transceiver Chip Set
The Intersil 2.4GHz PRISM chip set is
a highly integrated six-chip solution for
RF modems employing Direct Sequence
Spread Spectrum (DSSS) signaling.
Significant integration of transmit and
receive functions employ the following ICs: complete integrated
DSSS engine, the HFA3824; a quadrature
modulator/demodulator, integrated with an IF limiter amplifier
with RSSI, the HFA3724, HFA3726; a combined LNA/Mixer
and upconverter/preamplifier, the HFA3624; a high
performance, low noise amplifier for increased receiver
sensitivity, the HFA3424; a dual synthesizer, the HFA3524 and
a monolithic RF power amplifier, the HFA3925. Each of the
functions may be used individually or in any combination in
support of a variety of RF modem applications.
The PRISM chip set is intended to support various data
rates including systems targeting the proposed IEEE 802.11
standard “Direct Sequence Physical layer (DS-PHY)”.
Differential BPSK and QPSK signaling is employed with
differential encoding and decoding of packetized data. A PN
sequence rate of up to 22 MCPS is supported for up to a 16
chip PN code. Integrated programmable low pass filters are
used on the HFA3724 to allow chip rates from 2.75 MCPS to
22 MCPS. A flexible general purpose data and control
interface is provided for parameter configuration and for
transferring data packets between the PHY and Media Access
Control (MAC) layers. Data rates of up to 2 MBPS for DBPSK
and 4 MBPS for DQPSK are supported.
Features
Provides Antenna-to-Bits Data Stream
Low Voltage Operation from 2.7V to 5.5V
2.4GHz - 2.5GHz ISM Band Operation
Single Heterodyne Conversion
Programmable Antialiasing and Shaping Filters
10MHz to 400MHz IF Operation with RSSI
Autonomous Half Duplex Direct Sequence Modem
Selectable DBPSK, DQPSK Signalling
Antenna Diversity Selection
Direct Sequence Physical Layer (DS-PHY)
Differential Data Encoding/Decoding
Programmable 16-Bit PN Code
Data Rates up to 4 MBPS DQPSK
Power Management Control
Low Profile PCMCIA-Compatible Surface Mount
Packaging
Applications
Systems Targeting IEEE 802.11 Standard
PCMCIA Wireless Transceiver
WLAN RF Modems
TDMA Packet Protocol Radios
Part 15 Compliant Radio Links
Typical Application Diagram
QUAD IF MODULATOR
RFPA
HFA3925
(FILE# 4132)
HFA3724, HFA3726
(FILE# 4067, 4310)
DSSS BASEBAND PROCESSOR
D
C
HFA3824
(FILE# 4308)
TUNE/SELECT
HFA3524/A
0
o
/90
o
VCO
A/D
A/D
MAC-PHY
INTERFACE
802.11
VCO
DUAL SYNTHESIZER
HFA3624
UP/DOWN
CONVERTER
(FILE# 4066)
A/D
(FILE# 4062)
PRISM CHIP SET FILE #4063
M
U
X
M
U
X
DPSK
DEMOD
DPSK
MOD.
DE-
SPREAD
SPREAD
Q
I
HFA3424
(NOTE)
(FILE# 4131)
NOTE: Required for systems targeting 802.11 specifications.
CCA
RXI
RXQ
RSSI
TXI
TXQ
÷
2
Data Sheet
August 1997
File Number
4063.6
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
http://www.intersil.com or 407-727-9207
|
Copyright
Intersil Corporation 1999
PRISM is a registered trademark of Intersil Corporation. PRISM logo is a trademark of Intersil Corporation.
Antenna to Bits is a trademark of Intersil Corporation.