ADL5350

Rev. 0 | Page 19 of 24

APPLICATIONS INFORMATION

LOW FREQUENCY APPLICATIONS

The ADL5350 can be used in low frequency applications. The

circuit in Figure 59 is designed for an RF of 136 MHz to 176 MHz

and an IF of 45 MHz using a high-side LO. The series and

parallel resonant circuits are tuned for 154 MHz, which is

the geometric mean of the desired RF frequencies. The

performance of this circuit is depicted in Figure 60.

RF/IF

GND2

LOIN

NC

RF/IF

NC

VPOS

100nH

100nF

4.7µF

27pF

36nH

10nF

27pF

LO

1nF

36nH

RF

3V

IF

GND1

ADL5350

12

3

4

87

6

5

ALL INDUCTORS

ARE 0603CS

SERIES FROM

COILCRAFT

Figure 59. 136 MHz to 176 MHz RF Downconversion Schematic

40

35

30

25

20

15

10

12

10

8

6

4

2

0

136

176

166

156

146

RF FREQUENCY (MHz)

IIP3

IP1dB

LOSS

Figure 60. Measured Performance for Circuit in Figure 59

Using High-Side LO Injection and 45 MHz IF

HIGH FREQUENCY APPLICATIONS

The ADL5350 can be used at extended frequencies with

some careful attention to board and component parasitics.

Figure 61 is an example of a 2560 MHz to 2660 MHz down-

conversion using a low-side LO. The performance of this circuit

is depicted in Figure 62. Note that the inductor and capacitor

values are very small, especially for the RF and IF ports. Above

2.5 GHz, it is necessary to consider alternate solutions to avoid

unreasonably small inductor and capacitor values.

RF/IF

GND2

LOIN

NC

RF/IF

NC

VPOS

2.1nH

100pF

4.7µF

0.7pF

1.5nH

1nF

1pF

0.67nH

RF

3V

IF

GND1

ADL5350

12

3

4

87

6

5

3.0nH

LO

100pF

ALL INDUCTORS

ARE 0302CS

SERIES FROM

COILCRAFT

Figure 61. 2560 MHz to 2660 MHz RF Downconversion Schematic

35

30

25

20

15

10

5

0

14

13

12

11

10

9

8

7

2560

2660

2580

2600

2620

2640

RF FREQUENCY (MHz)

IIP3

IP1dB

LOSS

Figure 62. Measured Performance for Circuit in Figure 61

Using Low-Side LO Injection and 374 MHz IF

The typical networks used for cellular applications below

2.6 GHz use band-select and band-reject networks on the RF

and IF ports. At higher RF frequencies, these networks are not

easily realized by using lumped element components. As a result, it

is necessary to consider alternate filter network topologies to

allow more reasonable values for inductors and capacitors.