MAX2022ETX+TD Maxim Integrated, MAX2022ETX+TD Datasheet - Page 12

• Manufacturer Part Number: MAX2022ETX+TD
• Description: Modulator / Demodulator 1.5-2.5GHz Quadratr Modulator
• Manufacturer: Maxim Integrated

Specifications of MAX2022ETX+TD

• Rohs: yes

MAX2022
Pin Description (continued)
Detailed Description
The MAX2022 is designed for upconverting differential
in-phase (I) and quadrature (Q) inputs from baseband to
a 1500MHz to 3000MHz RF frequency range. The device
can also be used as a demodulator, downconverting an
RF input signal directly to baseband or an IF frequency.
Applications include single and multicarrier 1500MHz
to 3000MHz UMTS/WCDMA, LTE/TD-LTE, cdma2000,
and DCS/PCS base stations. Direct conversion architec-
tures are advantageous since they significantly reduce
transmitter or receiver cost, part count, and power con-
sumption as compared to traditional IF-based double-
conversion systems.
The MAX2022 integrates internal baluns, an LO buffer, a
phase splitter, two LO driver amplifiers, two matched dou-
ble-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.
LO Input Balun, LO Buffer, and Phase Splitter
The MAX2022 requires a single-ended LO input, with a
nominal power of 0dBm. An internal low-loss balun at
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 splitter,
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.
www.maximintegrated.com
PIN
21
23
25
26
31
33
—
VCCLOQ2
VCCLOQ1
NAME
BBQN
BBQP
BBIN
RF
EP
Baseband In-Phase Negative Input
RF Port
Baseband Quadrature Negative Input
Baseband Quadrature Positive Input
Q-Channel 2nd LO Amplifier Supply Voltage
Q-Channel 1st LO Amplifier Supply Voltage
Exposed Ground Paddle. The exposed paddle MUST be soldered to the
ground plane using multiple vias.
Downconversion 1500MHz to 3000MHz
LO Driver
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 levels. 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.
I/Q Modulator
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 500MHz with differential amplitudes
up to 2V
The wide input bandwidth allows for direct interface with
the baseband DACs. No active buffer circuitry between
the baseband DAC and the MAX2022 is required.
The I and Q signals directly modulate the 0° and 90° LO
signals and are upconverted to the RF frequency. The
outputs of the I and Q mixers are combined through a
balun to a singled-ended RF output.
Applications Information
LO Input Drive
The LO input of the MAX2022 requires a single-ended
drive at a 1500MHz to 3000MHz frequency. It is internally
matched to 50Ω. An integrated balun converts the single-
ended input signal to a differential signal at the LO buffer
differential input. An external DC-blocking capacitor is the
only external part required at this interface. The LO input
power should be within the -3dBm to +3dBm range.
Quadrature Modulator/Demodulator
P-P
High-Dynamic-Range, Direct Up/
differential (common-mode input equals 0V).
FUNCTION
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