Power amplifier and communication unit

• US 6,313,699 B1
• Filed: 06/13/2000
• Issued: 11/06/2001
• Est. Priority Date: 09/29/1995
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Sportstation
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ishikawa, Osamu, Kunihisa, Taketo, Nishijima, Masaaki
• Primary Examiner(s): Shingleton, Michael B
• Application Number:
  US09/593,123
• Time in Patent Office: 511 Days
• Field of Search: 455/126, 330/51, 330/129, 330/302
• US Class Current: 330/51
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/372 Noise reduction and elimination in amplifier
• CPC Class Codes: H03F 2203/7215 the gated amplifier being switched on or off by a switch at the input of the amplifier
• CPC Class Codes: H03F 2203/7221 the gated amplifier being switched on or off by a switch at the output of the amplifier
• CPC Class Codes: H03F 2203/7231 the gated amplifier being switched on or off by putting into cascade or not, by choosing between amplifiers by one or more switch(es)
• CPC Class Codes: H03F 2203/7233 the gated amplifier, switched on or off by putting into parallel or not, by choosing between amplifiers by one or more switch(es), being impedance adapted by switching an adapted passive network
• CPC Class Codes: H03F 2203/7236 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers by (a ) switch(es)
• CPC Class Codes: H03F 3/602 Combinations of several amplifiers
• CPC Class Codes: H03F 3/68 Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics power amplifiers using a combination of several semiconductor amplifiers H03F3/211; combinations of amplifiers using coupling networks with distributed constants H03F3/602
• CPC Class Codes: H03F 3/72 Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal

Abstract

A power amplifier including: a first amplifier PA2 having an input terminal and an output terminal; a passive circuit PC3 having an input terminal and an output terminal; and a first switch SW2 having a single-pole terminal and two multi-throw terminals, one of the multi-throw terminals of the first switch SW2 being connected to the input terminal of the first amplifier PA2 and the other of the multi-throw terminals of the first switch SW2 being connected to the input terminal of the passive circuit PC3. This makes it possible to provide a power amplifier and a communication unit which can be operated with different frequencies, output powers or modulation types.

Claims

1. A communication unit comprising:

a first amplifier having an input node and an output node;

a second amplifier having an input node and an output node operable in a first mode at a first frequency;

and output matching circuit having an input node and an output node operable in a second mode at a second frequency;

a first switch having a single-pole node and two or more multi-throw nodes;

a second switch having a single-pole node and two or more multi-throw nodes; and

an antenna,

wherein the output node of the first amplifier is connected to the single-pole node of the first switch,

at least one of the multi-throw nodes of the first switch is connected to the input node of the second amplifier and at least another multi-throw node of the first switch is connected to the input node of the output matching circuit,

the output node of the second amplifier is connected to one of the multi-throw nodes of the second switch and the output node of the output matching circuit is connected to another multi-throw node of the second switch,

the single-pole node of the second switch is connected to the antenna whereby in synchronization with the first switch, operation in either the first mode or the second mode is provided, and

the first frequency is different from the second frequency.

5. A communication unit according to claim 1, wherein an output power of the communication unit when operating in the first mode is the same as an output power of the communication unit when operating in the second mode.

2. A communication unit comprising:

a first amplifier having an input node and an output node;

a second amplifier having an input node and an output node operable in a first mode at a first frequency;

a third amplifier having an input node and an output node operable in a second mode at a second frequency;

a first switch having a single-pole node and two or more multi-throw nodes;

a second switch having a single-pole node and two or more multi-throw nodes; and

an antenna,

wherein the output node of the first amplifier is connected to the single-pole node of the first switch,

at least one of the multi-throw nodes of the first switch is connected to the input node of the second amplifier and at least another multi-throw node of the first switch is connected to the input node of the third amplifier,

the output node of the second amplifier is connected to one of the multi-throw nodes of the second switch and the output node of the third amplifier is connected to another multi-throw node of the second switch,

the single-pole node of the second switch is connected to the antenna whereby in synchronization with the first switch, operation in either the first mode or the second mode is provided, and

the first frequency is different from the second frequency.

6. A communication unit according to claim 2, wherein an output power of the communication unit when operating in the first mode is the same as an output power of the communication unit when operating in the second mode.

3. A communication unit comprising:

an amplifier having an input node and an output node;

a first output matching circuit having an input node and an output node operable in a first mode at a first frequency;

a second output matching circuit having an input node and an output node operable in a second mode at a second frequency;

a first switch having a single-pole node and two or more multi-throw nodes;

a second switch having a single-pole node and two or more multi-throw nodes; and

an antenna,

wherein the output node of the amplifier is connected to the single-pole node of the first switch,

at least one of the multi-throw nodes of the first switch is connected to the input node of the first output matching circuit and at least another multi-throw node of the first switch is connected to the input node of the second output matching circuit,

the output node of the first output matching circuit is connected to one of the multi-throw nodes of the second switch and the output node of the second output matching circuit is connected to another multi-throw node of the second switch,

the single-pole node of the second switch is connected to the antenna whereby in synchronization with the first switch, operation in either the first mode or the second mode is provided, and

the first frequency is different from the second frequency.

7. A communication unit according to claim 3, wherein an output power of the communication unit when operating in the first mode is the same as an output power of the communication unit when operating in the second mode.

4. A communication unit comprising:

a first passive output matching circuit having an input node and an output node operable in a first mode at a first frequency;

a second passive output matching circuit having an input node and an output node operable in a second mode at a second frequency;

a third passive output matching circuit having an input node and an output node;

a fourth passive output matching circuit having an input node and an output node;

a first switch having a single-pole node and two or more multi-throw nodes;

a second switch having a single-pole node and two or more multi-throw nodes;

a third switch having a single-pole node and two or more multi-throw nodes;

a fourth switch having a single-pole node and two or more multi-throw nodes;

an amplifier having an input node and an output node; and

an antenna,

wherein one of the multi-throw nodes of the first switch is connected to the input node of the first passive output matching circuit, another multi-throw node of the first switch is connected to the input node of the second passive output matching circuit and the output node of the amplifier is connected to the single-pole node of the first switch,

the single-pole node of the second switch is connected to an input, at least one of the multi-throw nodes of the second switch is connected to the input node of the third passive output matching circuit and at least another multi-throw node of the second switch is connected to the input node of the fourth passive output matching circuit,

the single-pole node of the third switch is connected to the input node of the amplifier, at least one of the multi-throw nodes of the third switch is connected to the output node of the third passive output matching circuit and at least another multi-throw node of the third switch is connected to the output node of the fourth passive output matching circuit,

one of the multi-throw nodes of the fourth switch is connected to the output node of the first passive output matching circuit and another multi-throw node of the fourth switch is connected to the output node of the second passive output matching circuit,

the single-pole node of the fourth switch is connected to the antenna whereby in synchronization with the first switch, operation in either the first mode or the second mode is provided, and

the first frequency is different from the second frequency.

8. A communication unit according to claim 4, wherein an output power of the communication unit when operating in the first mode is the same as an output power of the communication unit when operating in the second mode.