LTC5588-1
APPLICATIONS INFORMATION
RF Section
The RF port output impedance for EN = Low is given in
Table 9.
After upconversion, the RF outputs of the I and Q mixers
are combined. An on-chip balun performs internal dif-
ferential to single-ended conversion, while transforming
the output signal to 50Ω as shown in Figure 1.
Table 9. RF Output Impedance vs Frequency for EN = Low
REFLECTION COEFFICIENT
FREQUENCY
(MHz)
RF OUTPUT
IMPEDANCE
MAG
ANGLE
Table 8 shows the RF port output impedance vs frequency
for EN = High.
0.2
0.25
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.2
1.4
1.6
1.8
1.9
2.0
2.5
3.0
3.2
3.5
4.0
4.5
5.0
5.5
6.0
7.2+j11
8.0+j13
9.0+j16
12+j21
15+j25
19+j29
23+j32
29+j34
35+j35
40+j34
51+j28
57+j18
57+j7.0
53+j0.4
51-j2.4
48-j4.0
38-j4.9
31-j0.7
29+1.0
27+j3.6
24+j5.6
22+j6.9
19+j11
17+j20
15+j28
0.761
0.742
0.720
0.675
0.622
0.571
0.518
0.464
0.414
0.363
0.266
0.175
0.090
0.030
0.025
0.044
0.153
0.240
0.266
0.308
0.365
0.405
0.478
0.563
0.628
155
149
144
133
123
115
107
99
Table 8. RF Output Impedance vs Frequency for EN = High
REFLECTION COEFFICIENT
FREQUENCY
(MHz)
RF OUTPUT
IMPEDANCE
MAG
0.742
0.723
0.702
0.660
0.609
0.560
0.509
0.457
0.409
0.359
0.266
0.180
0.098
0.042
0.032
0.043
0.142
0.227
0.255
0.298
0.365
0.406
0.475
0.541
0.613
ANGLE
154
149
143
133
123
114
106
98
0.2
0.25
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.2
1.4
1.6
1.8
1.9
2.0
2.5
3.0
3.2
3.5
4.0
4.5
5.0
5.5
6.0
7.8+j11
8.7+j13
9.7+j16
12+j21
16+j25
19+j29
24+j32
30+j34
35+j35
41+j34
52+j28
58+j18
58+j7.1
55+j0.2
52-j2.7
50-j4.3
39-j5.9
32-j1.9
30-j0.2
27+j2.2
23+j4.5
22+j6.8
19+j11
17+j20
15+j27
92
86
72
60
43
91
7.0
85
–74
–111
–155
–177
–177
169
164
161
151
132
118
70
57
39
3.4
–52
–92
–149
–173
–180
172
167
161
151
133
120
55881fb
23
Linear [ Linear ]
