HFA3724 Datasheet, PDF (1/24 Pages) Intersil Corporation – 400MHz Quadrature IF Modulator/Demodulator

Data Sheet
HFA3724
November 1999 File Number 4067.7
400MHz Quadrature IF
Modulator/Demodulator
™ The Intersil 2.4GHz PRISM™ chip set is a
highly integrated five-chip solution for RF
modems employing Direct Sequence
Spread Spectrum (DSSS) signaling. The
HFA3724 400MHz Quadrature IF
Modulator/Demodulator is one of the five chips in the PRISM™
chip set (see the Typical Application Diagram).
The HFA3724 is a highly integrated baseband converter for
quadrature modulation applications. It features all the necessary
blocks for baseband modulation and demodulation of I and Q
signals. It has a two stage integrated limiting IF amplifier with 84db
of gain with a built in Receive Signal Strength Indicator (RSSI).
Baseband antialiasing and shaping filters are integrated in the
design. Four filter bandwidths are programmable via a two bit
digital control interface. In addition, these filters are continuously
tunable over a ±20% frequency range via one external resistor. The
modulator channel receives digital I and Q data for processing. To
achieve broadband operation, the Local Oscillator frequency input
is required to be twice the desired frequency of
modulation/demodulation. A selectable buffered divide by 2 LO
output and a stable reference voltage are provided for convenience
of the user. The device is housed in a thin 80 lead TQFP package
well suited for PCMCIA board applications.
Ordering Information
PART NUMBER
HFA3724IN
HFA3724IN96
TEMP. RANGE
(^oC)
-40 to 85
-40 to 85
PACKAGE
80 Ld TQFP
Tape and Reel
PKG. NO.
Q80.14x14
Simplified Block Diagram
Features
• Integrates all IF Transmit and Receive Functions
• Broad Frequency Range . . . . . . . . . . . 10MHz to 400MHz
• I/Q Amplitude and Phase Balance . . . . . . . . . . . 0.2dB, 2^o
• 5th Order Programmable
Low Pass Filter. . . . . . . . . . . . . . . . . . . 2.2MHz - 17.6MHz
• 400MHz Limiting IF Gain Strip with RSSI. . . . . . . . . .84dB
• Low LO Drive Level . . . . . . . . . . . . . . . . . . . . . . . -15dBm
• Fast Transmit-Receive Switching . . . . . . . . . . . . . . . . . 1µs
• Power Management/Standby Mode
• Single Supply 2.7V to 5.5V Operation
Applications
• Systems Targeting IEEE 802.11 Standard
• TDD Quadrature-Modulated Communication Systems
• Wireless Local Area Networks
• PCMCIA Wireless Transceivers
• ISM Systems
• TDMA Packet Protocol Radios
• PCS/Wireless PBX
• Wireless Local Loop
LIM1_IN _IF
RSSI1
RSSI2
MOD_LO_IN
MOD_LO_OUT
LO_GND
MOD_TX_IF_OUT
IF
I
÷2
0^o/90^o
M
U
M
U
X
X
Q
∑
2V
REF
LPF_RXI_OUT
LPF_RXQ _OUT
LPF_TXI_IN
LPF_TXQ_IN
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143 | Copyright © Intersil Corporation 1999
PRISM® is a registered trademark of Intersil Corporation. PRISM logo is a trademark of Intersil Corporation.