MAX2022ETX Maxim Integrated Products, MAX2022ETX Datasheet - Page 9

• Manufacturer Part Number: MAX2022ETX
• Description: Modulator / Demodulator High-Dynamic-Range D irect Upconversion 1
• Manufacturer: Maxim Integrated Products

The MAX2022 is designed for upconverting differential
in-phase (I) and quadrature (Q) inputs from baseband to
a 1500MHz to 2500MHz RF frequency range.
Applications include single and multicarrier 1800MHz to
2200MHz UMTS/WCDMA, cdma2000, and DCS/PCS
base stations. Direct upconversion architectures are
advantageous since they significantly reduce transmitter
cost, part count, and power consumption as compared
to traditional IF-based double upconversion systems.
The MAX2022 integrates internal baluns, an LO buffer, a
phase splitter, two LO driver amplifiers, two matched
double-balanced passive mixers, and a wideband
quadrature combiner. Precision matching between the
in-phase and quadrature channels, and highly linear
mixers achieves excellent dynamic range, ACLR, 1dB
compression point, and LO and sideband suppression,
making it ideal for four-carrier WCDMA/UMTS operation.
The MAX2022 requires a single-ended LO input, with a
nominal power of 0dBm. An internal low-loss balun at
1, 5, 9–12, 14,
16–19, 22, 24,
27–30, 32, 34,
35, 36
PIN
EP
13
15
20
21
23
25
26
31
33
2
3
4
6
7
8
1500MHz to 2500MHz Quadrature Modulator
High-Dynamic-Range, Direct Upconversion
LO Input Balun, LO Buffer, and
RBIASLO3
RBIASLO1
RBIASLO2
VCCLOQ2
VCCLOQ1
VCCLOI1
VCCLOI2
VCCLOA
_______________________________________________________________________________________
RFOUT
NAME
COMP
BBQN
BBQP
BBIN
GND
BBIP
GND
LO
Detailed Description
Ground
3rd LO Amplifier Bias. Connect a 301Ω resistor to ground.
LO Input Buffer Amplifier Supply Voltage
Local Oscillator Input. 50Ω input impedance.
1st LO Input Buffer Amplifier Bias. Connect a 432Ω resistor to ground.
Compensation Capacitor Input. Connect a 22pF capacitor to ground.
2nd LO Amplifier Bias. Connect a 562Ω resistor to ground.
I-Channel 1st LO Amplifier Supply Voltage
I-Channel 2nd LO Amplifier Supply Voltage
Baseband In-Phase Positive Input
Baseband In-Phase Negative Input
RF Output
Baseband Quadrature Negative Input
Baseband Quadrature Positive Input
Q-Channel 1st LO Amplifier Supply Voltage
Q-Channel 2nd LO Amplifier Supply Voltage
Exposed Ground Paddle. The exposed paddle MUST be soldered to the ground plane using
multiple vias.
Phase Splitter
the LO input converts the single-ended LO signal to a
differential signal at the LO buffer input. In addition, the
internal balun matches the buffer’s input impedance to
50Ω over the entire band of operation.
The output of the LO buffer goes through a phase split-
ter, which generates a second LO signal that is shifted
by 90° with respect to the original. The 0° and 90° LO
signals drive the I and Q mixers, respectively.
Following the phase splitter, the 0° and 90° LO signals
are each amplified by a two-stage amplifier to drive the
I and Q mixers. The amplifier boosts the level of the LO
signals to compensate for any changes in LO drive lev-
els. The two-stage LO amplifier allows a wide input
power range for the LO drive. While a nominal LO
power of 0dBm is specified, the MAX2022 can tolerate
LO level swings from -3dBm to +3dBm.
The MAX2022 modulator is composed of a pair of
matched double-balanced passive mixers and a balun.
The I and Q differential baseband inputs accept signals
from DC to beyond 100MHz with differential amplitudes
FUNCTION
Pin Description
I/Q Modulator
LO Driver
9