1
Description
LTC5569
300MHz to 4GHz 3.3V DUAL
ACTIVE DOWNCONVERTING MIXER
Demonstration circuit DC1719A is optimized for evaluation
of the LTC
®
5569 dual active downconverting mixer. Its RF
and LO input ports are internally matched to 50Ω from
1.4GHz to 3.3GHz, and from 1GHz to 3.5GHz, respectively.
The IF output uses a bandpass network followed by an
8:1 transformer to provide a 50Ω match at 190MHz. The
LTC5569 dual active mixer is optimized for diversity and for
MIMO receiver applications that require low power and small
size. Each mixer includes an independent LO buffer amplifier,
an active mixer core, and a bias circuit with an enable pin.
The symmetry of the IC assures that a phase and ampli-
tude coherent LO is applied to each mixer. Broadband
integrated transformers on the RF and LO inputs provide
single-ended 50Ω interfaces. The differential IF outputs
allow convenient interfacing to differential IF filters and
amplifiers.
Design files for this circuit board are available at
http://www.linear.com/demo
BoarD photo
Figure 1. Test Setup for Mixer 2-Tone Measurements
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
aBsolute MaxiMuM ratings
Supply Voltage (V
CCA
, V
CCB
, IFA
+
, IFA
–
,
IFB
+
, IFB
–
) ...................................................................4V
Enable Input Voltage (ENA, ENB) ......–0.3V to V
CC
+ 0.3V
Mixer Bias Voltage (BIASA, BIASB) ....–0.3V to V
CC
+ 0.3V
LO Input Power (350MHz to 4.3GHz) ...................10dBm
LO Input DC Voltage ............................................... ±0.1V
RF Input Power (300MHz to 4GHz) ......................15dBm
RF Input DC Voltage (RFA, RFB) ............................ ±0.1V
Operating Temperature Range (T
C
) ........ –40°C to 105°C
Junction Temperature (T
J
) .................................... 150°C
Storage Temperature Range .................. –65°C to 150°C
CAUTION: This part is sensitive to electrostatic discharge
(ESD). Observe proper ESD precautions when handling
the LTC5569.