5

CMPA0060002D Rev 1.1

Cree, Inc.

4600 Silicon Drive

Durham, North Carolina, USA 27703

USA Tel: +1.919.313.5300

Fax: +1.919.869.CREE

www.cree.com/wireless

Copyright © 2009-2012 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree

and the Cree logo are registered trademarks of Cree, Inc. Other trademarks, product and company names are the property of their

respective owners and do not imply specific product and/or vendor endorsement, sponsorship or association.

External Termination Reference Design

The following is a plot of the gain of the die only.

Notes:

1

An off chip termination is needed to reduce the high gain peak at low frequencies.

2

The off chip termination should be designed to minimize the impact on the MMIC’s performance at higher

frequencies.

LRC Reference Circuit

The Drain and Gate circuit use the same L and C components but different values for the resistor.

Figure 2.

The Drain resistor needs to be dimensioned to handle 3 W of RF dissipation for the lowest frequencies while the Gate

resistor needs to handle 0.5 W. The suppliers of the SMT components are:

L1 = 47 nH, CoilCraft PN: 0402CS –47NXJB

C1 = 470 pf Murata PN: GRM1885C2A471A01D

Die only

10

12

14

16

18

20

22

24

26

28

30

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

Frequency (GHz)

S21 (Die Only)