LTC5591 datasheet(14/20 Pages) LINER

14 / 20 page

LTC5592

5592f

The RF input impedance and input reflection coefficient,

versus RF frequency, are listed in Table 1. The reference

plane for this data is Pin 1 of the IC, with no external

matching, and the LO is driven at 2.16GHz.

Table 1. RF Input Impedance and S11

(at Pin 1, No External Matching, fLO = 2.16GHz)

FREQUENCY

(GHz)

RF INPUT

IMPEDANCE

S11

MAG

ANGLE

1.6

66.0 + j6.8

0.15

1.7

62.4 + j0.5

0.11

1.8

57.9 – j3.8

0.08

–24

1.9

53.2 – j6.1

0.07

–59

2.0

48.5 – j8.8

0.09

–95

2.1

40.6 – j9.3

0.14

–130

2.2

35.0 – j0.1

0.18

–180

2.3

39.3 + j3.7

0.13

–201

2.4

41.2 + j3.9

0.11

–207

2.5

41.7 + j4.3

0.10

–211

2.6

42.8 + j4.1

0.09

–212

2.7

44.1 + j3.6

0.07

–213

APPLICATIONS INFORMATION

Figure 5. LO Input Schematic

LO Input

The LO input, shown in Figure 5, is connected to the

primary winding of an integrated transformer. A 50Ω

impedance match is realized at the LO port by adding

an external series capacitor, C2. This capacitor is also

needed for DC blocking if the LO source has DC voltage

present, since the primary side of the LO transformer is

DC-grounded internally. The DC resistance of the primary

is approximately 1.8Ω.

The secondary of the transformer drives a pair of high

speed limiting differential amplifiers for channels A and B.

The LTC5592’s LO amplifiers are optimized for the 1.7GHz

to 2.5GHz LO frequency range; however, LO frequencies

outside this frequency range may be used with degraded

performance.

The LO port is always 50Ω matched when VCC is applied,

even when one or both of the channels is disabled. This

helps to reduce frequency pulling of the LO source when

the mixer is switched between different operating states.

Figure 6 illustrates the LO port return loss for the different

operating modes.

Figure 6. LO Input Return Loss

The nominal LO input level is 0dBm, though the limiting

amplifiers will deliver excellent performance over a ±6dBm

input power range. Table 2 lists the LO input impedance

and input reflection coefficient versus frequency.

Table 2. LO Input Impedance vs Frequency

(at Pin 16, No External Matching, ENA = ENB = High)

FREQUENCY

(GHz)

INPUT

IMPEDANCE

S11

MAG

ANGLE

1.7

46.4 + j34.4

0.34

1.8

47.0 + j31.0

0.31

1.9

46.5 + J28.2

0.28

2.0

44.4 + J26.8

0.28

2.1

43.1 + j26.0

0.28

2.2

41.8 + j26.2

0.29

2.3

40.4 + j27.4

0.31

2.4

38.8 + j28.5

0.33

2.5

38.0 + j30.4

0.35

FREQUENCY (MHz)

1700

–30

–20

–25

–15

–10

–5

5592 F06

1900

2100

2300

2500

BOTH CHANNELS ON

ONE CHANNEL ON

BOTH CHANNELS OFF

MIXER B

LTC5592

ISEL

5592 F05

ENA

ENB

BIAS

MIXER A

LTC5591 датащи(PDF) 14 Page - Linear Technology

LTC5591 датащи(HTML) 14 Page - Linear Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

датащи скачать

ссылки URL