Data Sheet

ADRF5440

APPLICATIONS INFORMATION

analog.com

Rev. A | 16 of 18

RECOMMENDATIONS FOR PCB DESIGN

The RF ports are matched to 50Ω internally, and the pinout is

designed to mate a coplanar waveguide (CPWG) with 50Ω charac-

teristic impedance on the PCB. Figure 26 shows the referenced

CPWG design for a 150µm thick Megtron6 2×1080 R‑5775G dielec-

tric material. The RF trace with 300µm width and 300µm gap is

used for 42µm finished copper thickness.

Figure 26. Probe Board Stackup

Figure 27. Recommended RF Pin Transitions

Table 8 shows the recommended layout from the device RF pins

to the 50Ω CPWG. Signal pads have a 170µm diameter extended

with a neck for broadband tuning and tapered to RF trace with a 45°

angle. The optimized RF pin transitions for broadband performance

is given for different stackups in Table 8. For further recommenda-

tions on alternate PCB stackups with different dielectric thickness

and CPWG design, contact Analog Devices, Inc., Analog Devices

Support.

Table 8. Recommended RF Pin Transitions for Different Stackups

RF Stack-Up Height and Dielectric

RF Trace Dimensions

ADRF5440 Mnemonic

Transition Dimensions

H (µm)

Er

W (µm)

G (μm)

N (µm)

L (µm)

85

3.02

180

250

RFC, RF1, and RF4

120

90

RF2 and RF3

120

190

100

3.34

200

225

RFC, RF1, and RF4

120

90

RF2 and RF3

120

140

115

3.40

225

250

RFC, RF1, and RF4

120

90

RF2 and RF3

120

140

125

3.00

250

225

All

120

90

1501

3.40

300

300

All

120

90

175

3.16

360

245

All

170

90

190

3.00

425

225

All

170

90

200

3.55

425

275

All

170

90

1 Design reference and generic footprint.