ADRF5026

Data Sheet

Rev. A | Page 12 of 13

Narrow-Band Impedance Matching

5G mmWave Frequencies

Narrow-band impedance matching on the RF transmission

lines can improve return loss and insertion loss for a targeted

frequency range. The impedance matched circuit, highlighted

in Figure 22, achieves a flat insertion loss response of 2.4 dB

from 28 GHz to 43 GHz (see Figure 23). The dimensions of the

50 Ω lines are 14 mil trace width and a 7 mil gap. To implement

this impedance matched circuit, an 8 mil trace with a width of

5 mil is inserted between the pin pad and the 50 Ω trace.

Table 7, Figure 23, Figure 24, and Figure 25 show the measured

performance of ADRF5026 on the impedance matched circuit

on the probe matrix board.

RFC

VSS

EN

CTRL

VDD

RF2

EPAD

RF1

7mil

7mil

5mil

8mil 10mil

14mil

Figure 22. Impedance Matched Circuit

Table 7. Impedance Matched Parameters

Parameter

Test Condition

Typ

Unit

Insertion Loss

See Figure 23

Between RFC and RF1/RF2

100 MHz to 18 GHz

1.3

dB

18 GHz to 26 GHz

2.0

dB

26 GHz to 35 GHz

2.4

dB

35 GHz to 40 GHz

2.4

dB

40 GHz to 44 GHz

2.5

dB

Return Loss

See Figure 24

RFC and RF1/RF2 (On)

100 MHz to 18 GHz

17

dB

18 GHz to 26 GHz

10

dB

26 GHz to 35 GHz

7

dB

35 GHz to 40 GHz

9

dB

40 GHz to 44 GHz

15

dB

RF1/RF2 (Off)

See Figure 24

100 MHz to 18 GHz

18

dB

18 GHz to 26 GHz

17

dB

26 GHz to 35 GHz

18

dB

35 GHz to 40 GHz

12

dB

40 GHz to 44 GHz

7

dB

0

–5

–4

–3

–2

–1

0

5

10

15

20

25

30

35

45

40

FREQUENCY (GHz)

Figure 23. Insertion Loss vs. Frequency, with Impedance Matching

0

–40

–35

–30

–25

–20

–15

–10

–5

0

5

10

15

20

25

30

35

40

45

FREQUENCY (GHz)

RF1/RF2 OFF

RF1/RF2 ON

RFC

Figure 24. Return Loss vs. Frequency, with Impedance Matching

0

–110

–70

–80

–90

–100

–60

–50

–40

–30

–20

–10

0

5

10

15

20

25

30

35

40

45

FREQUENCY (GHz)

RF1 TO RF2

RFC TO RF1/RF2

Figure 25. Isolation vs. Frequency, with Impedance Matching