adl5331 Analog Devices, Inc., adl5331 Datasheet - Page 14

• Manufacturer Part Number: adl5331
• Description: 1 Mhz To 1.2 Ghz Vga With 30 Db Gain Control Range
• Manufacturer: Analog Devices, Inc.

ADL5331
INTERFACING TO AN IQ MODULATOR
The basic connections for interfacing the ADL5331 with the
ADL5385
quadrature modulator with an output frequency range of
50 MHz to 2.2 GHz. It offers excellent phase accuracy and
amplitude balance, enabling high performance direct RF
modulation for communication systems.
The output of the ADL5385 is designed to drive 50 Ω loads and
easily interfaces with the ADL5331. The input to the ADL5331
can be driven single-ended, as shown in Figure 17. Similar
configurations are possible with the ADL537x family of
are shown in Figure 24. The ADL5385 is an RF
BASEBAND INPUTS
DIFFERENTIAL I/Q
DAC
DAC
LO
Figure 24. ADL5385 Quadrature Modulator and ADL5331 Interface
IBBP
IBBN
QBBP
QBBN
100pF
VPOS
5V
ADL5385
IQ MOD
100pF
COMM
VOUT
Rev. 0 | Page 14 of 16
10nF
10nF
quadrature modulators. These modulators can provide outputs
from 500 MHz to 4 GHz.
SOLDERING INFORMATION
On the underside of the chip scale package, there is an exposed
compressed paddle. This paddle is internally connected to the
chip’s ground. Solder the paddle to the low impedance ground
plane on the printed circuit board to ensure specified electrical
performance and to provide thermal relief. It is also recom-
mended that the ground planes on all layers under the paddle
be stitched together with vias to reduce thermal impedance.
INHI
INLO
GAIN CONTROL
VPOS
ADL5331
5V
RF VGA
COMM
OPLO
OPHI
68µH
5V
68µH
10nF
10nF
ETC1-1-13
RF OUTPUT