DESCRIPTION
Demonstration circuit 1048A is a 1.5GHz to 2.7GHz Direct
Conversion I/Q Receiver featuring the LT5575.
The LT®5575 is an 800MHz to 2.7GHz direct conversion
quadrature demodulator optimized for high linearity
receiver applications. It is suitable for communications
receivers where an RF signal is directly converted into I
and Q baseband signals with bandwidth up to 490MHz.
The LT5575 incorporates balanced I and Q mixers, LO
buffer amplifiers and a precision, high frequency quadrature
phase shifter. The integrated on-chip broadband
transformers provide 50W single-ended interfaces at
the RF and LO inputs. Only a few external capacitors
are needed for its application in an RF receiver system.
Demonstration circuit 1048A is designed for evaluating
the LT5575 in the frequency range between 1.5GHz and
2.7GHz. It can be optimized for input frequencies below
1.5GHz by installing external shunt capacitors at RF input
and LO input ports. Refer to the LT5575 data sheet
for details.
Design files for this circuit board are available. Call
the LTC factory.