AD8340 Datasheet, PDF (1/20 Pages) Analog Devices – 700 MHz to 1000 MHz RF Vector Modulator

FEATURES
Cartesian amplitude and phase modulation
700 MHz to 1.0 GHz frequency range
Continuous magnitude control of −2 dB to −32 dB
Continuous phase control of 0° to 360°
Output third-order intercept 24 dBm
Output 1 dB compression point 11 dBm
Output noise floor −149 dBm/Hz @ full gain
Adjustable modulation bandwidth up to 230 MHz
Fast output power disable
4.75 V to 5.25 V single-supply voltage
APPLICATIONS
RF PA linearization/RF predistortion
Amplitude and phase modulation
Variable attenuators and phase shifters
CDMA2000, GSM/EDGE linear power amplifiers
Smart antennas
GENERAL DESCRIPTION
The AD8340 vector modulator performs arbitrary amplitude
and phase modulation of an RF signal. Since the RF signal path
is linear, the original modulation is preserved. This part can be
used as a general-purpose RF modulator, a variable attenu-
ator/phase shifter, or a remodulator. The amplitude can be
controlled from a maximum of −2 dB to less than −32 dB, and
the phase can be shifted continuously over the entire 360° range.
For maximum gain, the AD8340 delivers an OP1dB of 11 dBm,
an OIP3 of 24 dBm, and an output noise floor of −149 dBm/Hz,
independent of phase. It operates over a frequency range of
700 MHz to 1.0 GHz.
The baseband inputs in Cartesian I and Q format control the
amplitude and phase modulation imposed on the RF input
signal. Both I and Q inputs are dc-coupled with a ±500 mV
differential full-scale range. The maximum modulation band-
width is 230 MHz, which can be reduced by adding external
capacitors to limit the noise bandwidth on the control lines.
700 MHz to 1000 MHz
RF Vector Modulator
AD8340
FUNCTIONAL BLOCK DIAGRAM
VPRF
QBBP OBBM
VPS2
90°
RFIP
RFIM
0°
RFOP
RFOM
CMOP
IBBP IBBM
Figure 1.
DSOP
Both the RF inputs and outputs can be used differentially or
single-ended and must be ac-coupled. The RF input and output
impedances are nominally 50 Ω over the operating frequency
range. The DSOP pin allows the output stage to be disabled
quickly in order to protect subsequent stages from overdrive.
The AD8340 operates off supply voltages from 4.75 V to 5.25 V
while consuming approximately 130 mA.
The AD8340 is fabricated on Analog Devices’ proprietary, high
performance 25 GHz SOI complementary bipolar IC process. It
is available in a 24-lead Pb-free LFCSP package and operates
over a −40°C to +85°C temperature range. Evaluation boards
are available.
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
www.analog.com
Fax: [phone] © 2004 Analog Devices, Inc. All rights reserved.