Intersil Introduces New
2.4 GHz Extended Range Power Amplifier with Integrated Detector for Wireless
Networking Applications
- Intersil's ISL3985 Power Amplifier
doubles the throughput at maximum range
- Extends range by approximately 15%
for applications requiring "best" range performance
IRVINE,
Calif., Aug. 1, 2002 - Intersil Corporation (Nasdaq:ISIL), a world leader in
the design and manufacture of high performance analog and wireless networking
solutions, today introduced the ISL3985, a power amplifier (PA) with integrated
detector and "sleep mode" function that extends battery life.
Intersil's new
PA is designed to work with the complete range of PRISM(R) Wireless Local Area
Networking (WLAN) chip set solutions operating in the 2.4 GHz band. The ISL3985
is ideal for current Wi-Fi applications and emerging 802.11g products such as
access points (AP). Its higher output power increases range by up to 15 percent
and doubles the data throughput at maximum range. Applications for the ISL3985
include:
| -- |
Access Points and WLAN cards
targeting IEEE 802.11b, 11 Mbps standard. |
| -- |
Access Points and WLAN cards
targeting IEEE 802.11g, 54 Mbps draft standard. |
| -- |
Other 2.4 GHz Industrial
Scientific and Medical (ISM) band radios. |
| -- |
2.4 GHz time division multiplex
access (TDMA) packet protocol radios. |
The ISL3985 is a 2.4-GHz two-stage Radio-Frequency Power
Amplifier (RFPA) with a built-in detector. Cascaded output power is typically 21
dBm for the usual direct sequence spread spectrum (DSSS) signal and exceeds
Adjacent Channel Power Ratio (ACPR) specifications with less than -30dBc for the
first side lobe and less than -50 dBc for the second side lobe. The integrated
detector is accurate within +/- 1 dB over a 15 dB range. This allows an accurate
automatic level control function to be implemented. Packaging for the ISL3985 is
the very small 16-pad, 5 X 5 mm Quad Flatpack No leads (QFN) package that
conserves space and provides highly effective heat sinking to the main board.
Technical Features
| -- |
2.7 to 3.6 V single-supply
operation |
| -- |
21 dBm typical output power,
ACPR/DSSS (1st lobe less than -30 dBc, 2nd lobe less than -50 dBc) |
| -- |
28 dB typical overall two-stage
power gain |
| -- |
15 dB detector linear input
power range, +/- 1 dB detector accuracy |
| -- |
CMOS level compatible
"sleep mode" function |
| -- |
16-pad, 5 X 5 mm, QFN (Quad
Flatpack No leads) package compliant to JEDEC PUB95 MO-220 product
outlines |
Detailed Description
The performance of the ISL3985 RFPA can be optimized by
adjusting the value of an external, low temp co-resistor which sets bias
currents. External positive or negative voltages are not required to set the
bias current. The on-chip bias network provides optimum bias current and
temperature compensation.
The ISL3985's
power detect function provides a DC output voltage that is proportional to the
logarithm of the output power. The detector is accurate to within 0.5 dB at an
output power of 21 dBm. The slope of the detector output voltage is 100 mV/dB
over a 15 dB dynamic range. A simple use for the detector is to optimize output
power compensating for manufacturing deviations.
In a PRISM WLAN
application, the HFA3861B or HFA3863 baseband processor uses the detector's
output to dynamically monitor the ISL3985's output power. The output power is
changed as needed by adjusting the automatic gain control voltage of the HFA3783
IF quadrature modem. This is designed to provide the best possible error-free
data transfer rate in a given operating environment and helps compensate for
channel-to-channel and temperature related variability in the transmit chain.
The ISL3985's
"sleep mode" (power Up/Down) function does not require any external
circuitry. Fully integrating this function frees up board space and reduces
component count and cost. When the CMOS compatible Power Enable (PE) pin is
driven low, the total supply current to the RFPA drops to less than 50 uA,
typically in as little as 300 ns. Full output power returns within a few hundred
nanoseconds when the PE pin is driven high.
The ISL3985
Extended Range Power Amplifier is available in production volumes now.
Intersil + Elantec Means More for Our Customers
Intersil Corporation is a global semiconductor leader in
the design and manufacture of high performance analog and wireless networking
solutions. The acquisition of Elantec Semiconductor, Inc., expanded Intersil's
product portfolios to address four fast growing markets -- flat panel displays,
optical storage (CD and DVD recordable), power management, and wireless
networking. Intersil brings added customer value in providing complete silicon,
software and reference design solutions to new products that enhance the
computing experience for people wherever they live, work or travel. For more
information about Intersil or to find out how to become a member of our winning
team, visit the company's web site and career page at www.intersil.com
# # #
CONTACT:
Intersil
Corporation
Ron
Paciello, 321/724-7184
rpaciell@intersil.com
or
Ketchum
Kevin
Oates, 310/584-8331
kevin.oates@ketchum.com
