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8-460
RF3334
Rev A6 061016
Pin
Function
Description
Interface Schematic
1RFDEC
External decoupling capacitor for RF single-ended to differential con-
verter.
2RF
LNA Input, Internally matched to 75
Ω. Should be AC-coupled.
3GND
Ground.
4IFVCC
5V supply for IF section.
5
IFSET
IF Gain select. The resistance between this pin and pin 6 (IFSETB)
determines the gain of the IF amplifier. Maximum gain is achieved by
placing a short circuit between the pins. Larger values of resistance will
reduce the IF gain according to the following equation where R is the
value of resistance between pins 5 and 6.
IFGain=20log(1600/(R=75))15.
6IFSETB
Complementary IF Gain select.
7IFOUT
IF Amplifier Output. Differential output of the IF amplifier. The differen-
tial load across this pin and pin 8 (IFOUTB) should be 1k
Ω or greater
for optimal performance. The differential output impedance across this
pin and pin 8 in 10
Ω.
8IFOUTB
Complementary IF Amplifier Output.
9GND
Ground.
10
MIXLOADB
Complementary Mixer load.
11
MIXLOAD
Differential output of the RF mixer. A resonant load should be applied to
this pin and pin 10 (MIXLOADB) that will act as a bandpass filter at the
desired IF frequency. VCC should be supplied to this pin via an inductor
or a resistor. Use of a resistor will degrade intermodulation perfor-
mance.
100
Ω
RFDEC
V
CC
VBIAS
RF
IFSETB
IFSET
IFSETB
IFSET
IF OUT
VBIAS
V
CC
IF OUTB
VBIAS
V
CC
MIXLOAD
MIXLOADB
MIXLOAD
MIXLOADB