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dc2091afa
DEMO MANUAL DC2091A
Description
LTC5599
30MHz to 1300MHz Low Power
Direct Quadrature Modulator
Demonstration circuit 2091A is optimized for evaluation
of the
LTC
®
5599
low power direct quadrature modulator.
The balanced I and Q baseband input ports can be either
AC- or DC-coupled to a source with a common mode volt-
age level of about 1.4V. Fixed LC networks on the LO and
RF ports cover a continuous 90MHz to 1300MHz range.
The SPI interface controls the supply current, modulator
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
QuikEval is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
gain, and allows optimization of the LO carrier feedthrough
and side-band suppression.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2091A
MeasureMent setup
Figure 1. Test Setup for RF Performance Measurements
I+
I–
Q+
Q–
DC2091 F01
BB SIGNAL SOURCE
(V
CMBB
= 1.4V
DC
)
SPECTRUM
ANALYZER
LO SIGNAL
SOURCE
DC POWER SUPPLY
(3.3V)
– +
–3dB
–6dB
