LTM9005IV-AB#PBF Linear Technology, LTM9005IV-AB#PBF Datasheet - Page 15

• Manufacturer Part Number: LTM9005IV-AB#PBF
• Manufacturer: Linear Technology

Specifications of LTM9005IV-AB#PBF

• Lead Free Status / RoHS Status: Compliant

applicaTions inForMaTion
RF input impedance and S11 versus frequency (with no
external matching) are listed in Table 1 and referenced
to Pin M3. The S11 data can be used with a microwave
circuit simulator to design custom matching networks and
simulate board-level interfacing to the RF input filter.
Table 1 RF Input Impedance vs Frequency
RF Input Overload
In the event of an overload condition at the RF in-
put, (Applications to provide additional text following
characterization).
LO Input Port
The LO input, shown in Figure 6, is internally matched from
1GHz to 5GHz. The input match can be shifted down, as
low as 750MHz, with a single shunt capacitor (C4) on Pin
M6. One example is plotted in Figure 7 where C4 = 2.7pF
produces a 50MHz to 1GHz match.
FREQUENCY
(MHz)
1300
1700
1950
2200
2450
2700
3000
3300
3600
3900
300
450
600
900
50
IMPEDANCE
12.0 + j14.5
14.7 + j17.4
20.5 + j23.3
34.4 + j30.3
59.6 + j23.8
59.2 – j18.1
41.5 – j24.5
28.3 – j21.3
19.0 – j13.5
9.1 + j11.2
69.2 + j2.8
13.9 – j5.1
10.8 + j3.4
9.4 + j12.3
4.6 + j2.3
INPUT
0.832
0.706
0.639
0.588
0.506
0.380
0.299
0.163
0.184
0.274
0.374
0.481
0.568
0.645
0.700
MAG
S11
ANGLE
–120.3
–145.5
–167.3
174.7
153.8
145.8
138.7
123.4
–53.5
–94.2
171.9
151.4
97.5
55.8
6.9
LO input matching below 750MHz requires the series
inductor (L4)/shunt capacitor (C4) network shown in
Figure 6. Two examples are plotted in Figure 7 where
L4 = 2.7nH/C4 = 3.9pF produces a 650MHz to 830MHz
match and L4 = 10nH/C4 = 8.2pF produces a 460MHz to
560MHz match.
The optimum LO drive is –3dBm for LO frequencies above
1.2GHz, although the amplifiers are designed to accom-
modate several dB of LO input power variation without
significant mixer performance variation. Below 1.2GHz,
0dBm LO drive is recommended for optimum noise figure,
although –3dBm will still deliver good conversion gain
and linearity.
LO
IN
FOR LO < 1GHz
EXTERNAL
MATCHING
C4
L4
–10
–20
–30
0
0.3
C4 = 8.2pF
L4 = 10nH
Figure 7. LO Input Return Loss
15
Figure 6. LO Input Schematic
L4 = 2.7nH
C4 = 3.9pF
LO
V
CC1
LO FREQUENCY (GHz)
L4 = 0
C4 = 2.7pF
1
NO EXT
MATCH
REGULATOR
LTM9005
9005 F07
5
LIMITER
V
REF
15
9005 F06
TO
MIXER
9005p