Specifications and information are subject to change without notice

WJ Communications, Inc

• Phone 1-800-WJ1-4401 • FAX: 408-577-6621 • e-mail: sales@wj.com • Web site: www.wj.com

September 2004

The Communications Edge

TM

AH31

High Dynamic Range IF Amplifier

Product Information

Reference Design: 870 – 960 MHz

Typical Performance

Frequency

900 MHz

S21

16.8 dB

S11

-14 dB

S22

-11 dB

Output P1dB

+21 dBm

Output IP3

+41 dBm

Noise Figure

2.1 dB

Bias

5 V @ 150 mA

Notes:

1.

The amplifier should be connected directly to a +5 V regulator; no dropping resistor is required.

2.

If no DC signal is present at the input (pin 1), C1 can be removed. The gate is internally grounded in the amplifier.

3.

All components are of size 0603.

4.

This is a reference design only. Sample evaluation boards are not readily available for this circuit. The actual implementation can be achieved

by requesting an AH31 Evaluation board (any frequency) and replacing the passive components with the values given above.

Gainvs Frequency

25

°C

10

12

14

16

18

20

800

850

900

950

1000

Frequency (MHz)

S11, S22 vs Frequency

25

°C

-20

-15

-10

-5

0

800

850

900

950

1000

Frequency (MHz)

S11

S22

Typical Device Data

Freq (MHz)

S11 (dB)

S11 (ang)

S21 (dB)

S21 (ang)

S12 (dB)

S12 (ang)

S22 (dB)

S22 (ang)

50

-2.89

-5.15

16.14

175.42

-29.18

5.50

-11.16

-10.29

100

-2.89

-8.61

16.07

173.09

-29.05

8.21

-11.42

-11.71

200

-2.93

-16.91

15.99

167.64

-28.46

13.72

-11.47

-17.87

300

-2.96

-25.39

15.90

162.22

-27.82

17.52

-11.60

-25.22

400

-3.01

-33.42

15.78

156.27

-27.04

20.10

-11.73

-32.59

500

-3.10

-41.65

15.72

150.37

-26.35

22.46

-11.88

-40.41

600

-3.16

-49.82

15.54

144.69

-25.57

23.12

-12.01

-48.04

700

-3.23

-57.37

15.25

139.50

-24.79

22.98

-12.22

-55.71

800

-3.24

-65.10

15.14

134.31

-24.33

21.53

-12.37

-62.56

900

-3.30

-72.57

14.98

129.13

-23.74

19.94

-12.50

-69.95

1000

-3.38

-79.77

14.74

124.24

-23.15

18.03

-12.67

-77.38

AH31

RF OUT

C5

.01

µF

C6

100 pF

L2

39 nH

L1

12 nH

C4

100 pF

RF IN

C2

2.4 pF

C1

100 pF

R2

5.1

Ω