ADL5545

Data Sheet

Rev. B | Page 14 of 18

OPERATION DOWN TO 30 MHz

To operate the ADL5545 at frequencies below 100 MHz, a feed-

back network must be implemented between the input and output

ports of the device to ensure stability. Figure 35 shows a sample

configuration used to evaluate the device at frequencies below

100 MHz. Figure 36 to Figure 38 demonstrate the performance

of the device in this configuration.

1

2

(2)

3

ADL5545

L1

1000nH

VPOS

GND

RFIN

C1

100nF

RFOUT

C2

100nF

C6

10µF

C5

1nF

C4

100pF

RF

1500Ω

CF

10nF

Figure 35. Setup for Low Frequency Operation Down to 30 MHz

40

35

0

5

10

15

20

25

30

30

40

50

60

70

80

90

100

FREQUENCY (MHz)

P1dB

OIP3

GAIN

NOISE FIGURE

Figure 36. Noise Figure, Gain, P1dB, and OIP3 vs. Frequency,

30 MHz to 100 MHz

0

–5

–10

–15

–20

–35

–30

–25

30

40

50

60

70

80

90

100

FREQUENCY (MHz)

S12

S22

S11

Figure 37. Return Loss and Reverse Isolation, 30 MHz to 100 MHz

32

31

30

29

28

27

26

–7

–5

–3

1

–1

POUT PER TONE (dBm)

+85°C

+105°C

–40°C

+25°C

Figure 38. OIP3 vs. POUT at 30 MHz

W-CDMA ACPR PERFORMANCE

Figure 39 shows a plot of the adjacent channel power ratio

(ACPR) vs. POUT for the ADL5545. The signal type used is a

single wideband code division multiple access (W-CDMA)

carrier (Test Model 1-64) at 2140 MHz. This signal is generated

by a very low ACPR source. ACPR is measured at the output by

a high dynamic range spectrum analyzer that incorporates an

instrument noise-correction function.

0

–80

–70

–60

–50

–40

–30

–20

–10

–20

–15

–10

–5

0

5

POUT (dBm)

Figure 39. ACPR vs. POUT, Single W-CDMA Carrier (Test Model 1-64)

at 2140 MHz

The ADL5545 achieves an ACPR of −79 dBc at an output

power level of −4 dBm, at which point device noise and not

distortion begins to dominate the power in the adjacent

channels. At an output power level of 0 dBm, ACPR is still very

low at −69 dBc.