LT5522EUF Linear Technology, LT5522EUF Datasheet - Page 14

• Manufacturer Part Number: LT5522EUF
• Description: IC MIXER DWNCONV HI SIGN 16-QFN
• Manufacturer: Linear Technology
• Series: LT5522r

Specifications of LT5522EUF

• Rf Type: Cellular, PCS, UMTS
• Frequency: 400MHz ~ 2.7GHz
• Number Of Mixers: 1
• Gain: -0.2dB
• Noise Figure: 13.9dB
• Secondary Attributes: Down Converter
• Current - Supply: 68mA
• Voltage - Supply: 4.5 V ~ 5.25 V
• Package / Case: 16-WQFN Exposed Pad
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIO S I FOR ATIO
LT5522
inductor is recommended for L4 to preserve conversion
gain and minimize DC voltage drop to the IF
DC blocking capacitor and C3 is a bypass capacitor.
The narrowband bridge IF balun delivers good conversion
gain, linearity and noise figure over a limited IF bandwidth.
LO-IF leakage is approximately –32dBm, which is 17dB
worse than that obtained with a transformer. Typical IF
output return loss is plotted in Figure 13 for comparison
with other matching methods. Typical mixer performance
versus RF input frequency for 240MHz IF matching is
shown in Figure 16. Typical performance versus IF output
frequency for the same circuit is shown in Figure 17. The
results in Figure 17 show that the usable IF bandwidth is
approximately ±25MHz, assuming tight tolerance match-
ing components. Contact the factory for application assis-
tance with this circuit.
14
L1, L2 =
Figure 15. Narrowband Bridge IF Balun (240MHz Example)
C C
4 6
,
=
V
ω
CC
Z
•
IF
ω
•
Z
IF
IF
Z
U
IF
+
–
OUT
1
•
L4
390nH
Z
L2
100nH
OUT
C4
4.7pF
U
(Z
100nH
1000pF
4.7pF
L1
IF
C6
C3
= 400)
W
1000pF
5522 F15
C7
IF OUT
50Ω
+
pin. C7 is a
U
Figure 16. Typical Performance Using a
Narrowband Bridge Balun (Swept RF)
Figure 17. Typical Performance Using a
Narrowband Bridge Balun (Swept IF)
24
20
16
12
21
19
17
15
13
11
–1
4
0
9
7
5
3
1
8
1600
190
IIP3
G
200
C
1700
210
IF OUTPUT FREQUENCY (MHz)
RF INPUT FREQUENCY (MHz)
SSB NF
220
LO-IF
1800
IIP3
230
SSB NF
G
LO-IF
1900
C
240
250
2000
260
LOW SIDE LO
P
RF = 1900MHz
V
T
LOW SIDE LO
P
IF = 240MHz
V
T
LO
CC
A
LO
CC
A
= 25°C
= 25°C
270
= –5dBm
= 5VDC
= –5dBm
= 5VDC
2100 2200
280
5522 F16
5522 F17
290
10
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
30
10
–10
–30
–50
–70
–90
5522fa