Transmission output control circuit, and wireless device using the same

• US 7,299,015 B2
• Filed: 05/18/2005
• Issued: 11/20/2007
• Est. Priority Date: 05/27/2004
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Osumi, Yuji, Iwamiya, Hiroki
• Primary Examiner(s): Vuong; Quochien B.
• Application Number:
  US10/555,463
• Publication Number:
  US 20060240788A1
• Time in Patent Office: 916 Days
• Field of Search: 455/91, 455/127.1, 455/69, 455/115.1, 455/115.3, 455/126, 455/127.2, 455/522, 330/129, 330/135, 330/279, 330/282, 330/284, 330/285
• US Class Current: 455/127.1
• CPC Class Codes: H03F 1/0205 in transistor amplifiers
• CPC Class Codes: H03F 1/30 Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters in differential amplifiers H03F3/45479
• CPC Class Codes: H03F 1/345 using hybrid or directional couplers
• CPC Class Codes: H03F 2200/99 A diode as rectifier being used as a detecting circuit in an amplifying circuit
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/60 Amplifiers in which coupling networks have distributed constants, e.g. with waveguide resonators H03F3/54 takes precedence
• CPC Class Codes: H03G 3/3042 in modulators, frequency-changers, transmitters or power amplifiers transmission power control in bidirectional transmission systems H04W52/04
• CPC Class Codes: H04B 1/04 Circuits

Abstract

According to a transmitting output control circuit, one end of a coupling capacitor and one end of main line of a directional coupler are coupled with an output terminal of a power amplifier. A switch for coupling the other end of the coupling capacitor and one end of a sub line of the directional coupler with an anode of a first diode or a second terminating resistor is formed in a power amplifying apparatus. Any one of the coupling capacitor and the directional coupler is coupled by switching the switch. By using this structure, the stable transmitting power control circuit, which can be used in a wide dynamic range necessary for detecting a transmitting output signal level, can be provided.

Claims

1. A transmitting output control circuit comprising:

a power amplifying apparatus including;

a power amplifier;

a coupling capacitor for taking a part of a transmitting output signal of the power amplifier; and

a first diode for inputting a signal corresponding to an output signal amplified by the power amplifier and generating a detecting signal;

a directional coupler having a main line and sub line;

a first terminating resistor coupled with one end of the sub line of the directional coupler;

a switch disposed in the power amplifying apparatus;

a second terminating resistor coupled with the switch; and

a smoothing circuit coupled with a cathode of the first diode,

wherein one end of the coupling capacitor and one end of the main line of the directional coupler are coupled with an output terminal of the power amplifier,

wherein the switch is further coupled with an other end of the coupling capacitor, an other end of the sub line of the directional coupler, and an anode of the first diode, and the switch has a first state in which said other end of the coupling capacitor is coupled with the anode of the first diode and said other end of the sub line of the directional coupler is coupled with the second terminating resistor, and a second state in which said other end of the coupling capacitor is coupled with the second terminating resistor and said other end of the sub line of the directional coupler is coupled with the anode of the first diode,

wherein the part of the transmitting output signal of the power amplifier is taken through one of the coupling capacitor and the directional coupler by switching the first state and the second state of the switch.

2. The transmitting output control circuit of claim 1,

wherein the power amplifying apparatus, the first terminating resistor, the second terminating resistor and a load resistor forming the smoothing circuit are mounted at a surface layer of a multilayer board,

wherein the directional coupler is mounted at a dielectric layer of the multilayer board.

3. The transmitting output control circuit of claim 2,

wherein the second terminating resistor is built in the power amplifying apparatus.

4. The transmitting output control circuit of claim 2,

wherein the main line and the sub line of the directional coupler are formed of comb-shaped stripline electrodes provided in the dielectric layer of the multilayer board.

5. The transmitting output control circuit of claim 2,

wherein the smoothing circuit is formed of a smoothing capacitor and the load resistor,

wherein the smoothing capacitor is formed in such a manner that a ground electrode on the surface layer of the multilayer board and a capacitor electrode on the dielectric layer of the multilayer board face each other across the dielectric layer,

wherein one end of the load resistor is coupled with the ground electrode, and an other end of the load resistor is coupled with the capacitor electrode through a via hole of the multilayer board.

6. The transmitting output control circuit of claim 1,

wherein the power amplifying apparatus further includes:

a base bias terminal; and

a temperature compensating circuit coupled with the base bias terminal,

wherein variation in gain of the power amplifier depending on variation in an ambient temperature of the power amplifier is compensated by controlling a base bias voltage applied to the base bias terminal.

7. The transmitting output control circuit of claim 6,

wherein the temperature compensating circuit includes a second diode.

8. The transmitting output control circuit of claim 6,

wherein the temperature compensating circuit includes a bipolar transistor.

9. The transmitting output control circuit of claim 6,

wherein the temperature compensating circuit includes a MOSFET.

10. The transmitting output control circuit of any one of claims 1-9,

wherein the power amplifying apparatus, which includes the power amplifier, the first diode, the coupling capacitor, the switch and the temperature compensating circuit, is made into IC.

11. A wireless device comprising:

a transmitting section;

a controlling section;

the transmitting output control circuit of any one of claims 1-9; and

an antenna.