10
RF2619
Application Schematic
Measurement
Reference Plane
ZS=1 kΩ
IN+
IN-
10 nF
1
10 nF
2
ZIN=1 kΩ
3
4
5
GAIN
CONTROL
3.3 kΩ
16
GAIN
15
10 nF
14
10 nF
13
VCC
12
6
11
7
10
8
9
ZLOAD,EFF=500 Ω
R2 sets the balanced output impedance to 1 k Ω. L1 and C2
serve dual purposes. L1 serves as an output bias choke,
and C2 serves as a series DC block. In addition, the values
of L1 and C2 may be chosen to form an impedance
matching network if the load impedance is not 1k Ω .
Otherwise, the values of L1 and C1 are chosen to form a
parallel-resonant tank circuit at the IF when the IF filter's
input impedance is 1 k Ω.
C1 L1
C2
R2:
1 kΩ
C2
C1
L1 ZOUT=1 kΩ
VCC
10 nF
ZLOAD=1 kΩ
CDMA Filter
OUT+
OUT-
Measurement
Reference Plane
10-28
Rev B5 010720