Claims
- 1. A branching filter package comprising:
a SAW filter chip housing area which houses a piezo electric base, on which a transmitting SAW filter and a receiving SAW filter having a different frequency passing band with each other, are formed; an impedance matching circuit for said transmitting SAW filter and said receiving SAW filter; and a branching circuit for said transmitting SAW filter and said receiving SAW filter.
- 2. A branching filter package as claimed in claim 1, wherein said impedance matching circuit is formed by using a strip line circuit and an open circuit.
- 3. A branching filter package as claimed in claim 2 further comprising:
a first package base board and a second package base board, wherein said strip circuit is formed on said first package base board, and said open circuit and said branching circuit are formed on said second package base board.
- 4. A branching filter package as claimed in claim 2, wherein said branching circuit has a characteristic impedance lower than 50 ohm.
- 5. A branching filter package as claimed in claim 1 further comprising:
a plurality of package base boards, wherein an earth voltage pattern for said transmitting SAW filter and said receiving filter is formed separately on one of said plurality of package base boards.
- 6. A branching filter package as claimed in claim 1 further comprising:
a heat radiating opening which radiates a heat generated from said transmitting SAW filter and said receiving SAW filter out of said branching filter package.
- 7. A branching filter package as claimed in claim 1 further comprising:
a plurality of package base boards, wherein a spurious eliminating open stab, which is used as said impedance matching circuit, is formed on one of said plurality of package base boards.
Priority Claims (1)
Number |
Date |
Country |
Kind |
149959 |
May 1999 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of U.S. patent application Ser. No. 09/450,997, filed Nov. 29, 1999, and Japan Patent Application No. 149959, filed May 28, 1999, both of which are incorporated herein by reference.
[0002] This application also claims the priority of U.S. patent application Ser. No. 09/785,501, filed Feb. 20, 2001, U.S. patent application Ser. No. 09/305,304, filed May 5, 1999, issued as U.S. Pat. No. 6,222,426, and Japan Patent Application No. 10-160088, filed Jun. 9, 1998, all of which are incorporated herein by reference.
Continuation in Parts (3)
|
Number |
Date |
Country |
Parent |
09450997 |
Nov 1999 |
US |
Child |
10114326 |
Apr 2002 |
US |
Parent |
09305304 |
May 1999 |
US |
Child |
09450997 |
Nov 1999 |
US |
Parent |
09758501 |
Jan 2001 |
US |
Child |
09305304 |
May 1999 |
US |