3.5GHz Downconverter Mixers
with Selectable LO Doubler
Typical Operating Characteristics (continued)
(MAX2683/MAX2684 EV kit, VCC = +5V, RBIAS = 1.2kΩ, ENX2 = GND, fRF = 3.6GHz, PRF = -20dBm, fLOX2 = 1650MHz for MAX2683 or
fLOX2 = 1350MHz for MAX2684, PLO = -5dBm, all input/output ports terminated in 50Ω, IFOUT+ and IFOUT- matched to single-ended
50Ω load, TA = +25°C, unless otherwise noted.)
MAX2684
IF PORT S11 vs. RBIAS
RFIN S11 vs. RBIAS
1.2kΩ,
2kΩ, 820kΩ
2kΩ,
1.2kΩ, 820kΩ
PIN
1
2, 3, 5, 9,
10, 12, 13,
15, EP
4
6
7
8
11, 14
16
NAME
VCC
GND
RFIN
ENX2
LOX2
LOX1
IFOUT-,
IFOUT+
BIAS
Pin Description
FUNCTION
Supply Voltage Input. Bypass with a 100pF capacitor as close to the pin as possible.
Ground. Connect to ground plane with a low-inductance connection. Solder exposed paddle
evenly to the board ground plane.
RF Input Port to Mixer. Requires a matching network and a DC-blocking capacitor that may be part
of this network.
LO Frequency-Doubler Enable Input. Drive low to enable the LO doubler and run external LO at
half frequency. Drive high to disable the LO doubler and run external LO at full frequency.
Half-Frequency Local-Oscillator Input to LO Frequency Doubler, LO Filter, and Downconverter
Mixer. Requires a DC-blocking capacitor. Leave unconnected if this pin is not used.
Full-Frequency Local-Oscillator Input to Downconverter Mixer. Requires a DC-blocking capacitor.
Leave unconnected if this pin is not used.
Differential, Open-Collector IF Output Ports of Mixer. Requires a matching network and pull-up
inductors to VCC that can be part of this network.
Bias-Setting Resistor Connection. A resistor, RBIAS, placed from BIAS to GND sets the linearity and
supply current of the mixer.
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