MAX2023EVKIT+ Maxim Integrated, MAX2023EVKIT+ Datasheet - Page 3

• Manufacturer Part Number: MAX2023EVKIT+
• Description: Modulator / Demodulator MAX2023 Evaluation Kit
• Manufacturer: Maxim Integrated

Specifications of MAX2023EVKIT+

• Data Bus Width: 16 bit
• Interface Type: Direct Launch DAC interface
• Modulation Type: Quadrature
• Operating Supply Voltage: 4.75 V to 5.25 V
• Operating Temperature Range: - 40 C to + 85 C
• Operating Voltage: 4.75 V to 5.25 V
• Output Power: 5.6 dBm
• Supply Current: 295 mA

MAX2023 Evaluation Kit
As shown in Figure 1, providing an RC termination on
each of the I+, I-, Q+, Q- ports reduces the amount of
LO leakage present at the RF port under varying temp-
erature, LO frequency, and baseband drive conditions.
Note that the resistor value is chosen to be 50Ω with a
corner frequency 1 / (2πRC) selected to adequately filter
the f
of the baseband response at the highest baseband
frequency. The common-mode f
I+/I- and Q+/Q- effectively see the RC networks and
thus become terminated in 25Ω (R/2). The RC network
provides a path for absorbing the 2f
while the inductor provides high impedance at f
2f
The MAX2023 EV kit includes flexibility for a diplexer
network to be installed if desired. See Figure 3 for
details on the EV kit schematic.
Figure 1. Example Diplexer Network for GSM 1800/1900 Applications
4
LO
_______________________________________________________________________________________
LO
to help the diplexing process.
and 2f
LO
leakage, yet not affecting the flatness
Q
I
LO
L = 11nH
LO
C = 2.2pF
L = 11nH
C = 2.2pF
and 2f
and f
LO
LO
signals at
leakage,
LO
and
50Ω
50Ω
50Ω
50Ω
C = 2.2pF
C = 2.2pF
LO
The MAX2023 evaluation board can be a guide for your
board layout. Pay close attention to thermal design and
close placement of components to the IC. The
MAX2023 package’s exposed paddle (EP) conducts
heat from the device and provides a low-impedance
electrical connection to the ground plane. The EP must
be attached to the PCB ground plane with a low ther-
mal and electrical impedance contact. Ideally, this is
achieved by soldering the backside of the package
directly to a top metal ground plane on the PCB.
Alternatively, the EP can be connected to an internal or
bottom-side ground plane using an array of plated vias
directly below the EP. The MAX2023 EV kit uses nine
evenly spaced 0.016in-diameter, plated through holes
to connect the EP to the lower ground planes.
Depending on the ground plane spacing, large sur-
face-mount pads in the IF path may need to have the
ground plane relieved under them to reduce parasitic
shunt capacitance.
RF MODULATOR
MAX2023
90°
Layout Considerations
RF