POWER AMPLIFYING MODULE

• US 20150171796A1
• Filed: 12/05/2014
• Published: 06/18/2015
• Est. Priority Date: 12/12/2013
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Matsui, Toshiki
• Granted Patent: US 9,374,040 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03F 1/0222 by using a signal derived from the input signal
• CPC Class Codes: H03F 1/3223 using feed-forward H03F1/3211 takes precedence
• CPC Class Codes: H03F 1/56 Modifications of input or output impedances, not otherwise provided for
• CPC Class Codes: H03F 2200/111 the amplifier being a dual or triple band amplifier, e.g. 900 and 1800 MHz, e.g. switched or not switched, simultaneously or not
• CPC Class Codes: H03F 2200/222 A circuit being added at the input of an amplifier to adapt the input impedance of the amplifier
• CPC Class Codes: H03F 2200/318 A matching circuit being used as coupling element between two amplifying stages
• CPC Class Codes: H03F 2200/387 A circuit being added at the output of an amplifier to adapt the output impedance of the amplifier
• CPC Class Codes: H03F 2200/411 the output amplifying stage of an amplifier comprising two power stages
• CPC Class Codes: H03F 2200/429 Two or more amplifiers or one amplifier with filters for different frequency bands are coupled in parallel at the input or output
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2200/504 the supply voltage or current being continuously controlled by a controlling signal, e.g. the controlling signal of a transistor implemented as variable resistor in a supply path for, an IC-block showed amplifier
• CPC Class Codes: H03F 3/19 with semiconductor devices only
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/24 of transmitter output stages

Abstract

The linearity of a power amplifying module employing an envelope tracking scheme is improved. The power amplifying module includes a first bipolar transistor having a base to which a first radio frequency signal is input and an emitter grounded, and a second bipolar transistor having a base to which a first constant voltage is applied, a collector to which a first power supply voltage is applied, the first power supply voltage adapted to vary in accordance with an amplitude of the first radio frequency signal, and an emitter connected to a collector of the first bipolar transistor. The second bipolar transistor is configured to output a first amplified signal, obtained by amplifying the first radio frequency signal, from the collector of the second bipolar transistor.

Claims

1. A power amplifying module comprising:

a first bipolar transistor having a base to which a first radio frequency signal is input and an emitter grounded; and

a second bipolar transistor having a base to which a first constant voltage is applied, a collector to which a first power supply voltage is applied, the first power supply voltage adapted to vary in accordance with an amplitude of the first radio frequency signal, and an emitter connected to a collector of the first bipolar transistor, the second bipolar transistor configured to output a first amplified signal, obtained by amplifying the first radio frequency signal, from the collector of the second bipolar transistor.

2. The power amplifying module according to claim 1, further comprising:

a third bipolar transistor connected in an emitter-follower connection manner to the base of the first bipolar transistor and configured to supply a bias to the first bipolar transistor based on a first bias control voltage applied to a base of the third bipolar transistor; and

a constant voltage circuit configured to generate the first constant voltage based on the first bias control voltage.

3. The power amplifying module according to claim 1, further comprising:

a fourth bipolar transistor having a base to which a second radio frequency signal is input and an emitter grounded,

wherein the first power supply voltage adapted to vary in accordance with an amplitude of the first or second radio frequency signal selectively input is input to the collector of the second bipolar transistor, wherein the emitter of the second bipolar transistor is connected to the collector of the first bipolar transistor and to a collector of the fourth bipolar transistor, and wherein the second bipolar transistor is configured to output the first amplified signal, obtained by amplifying the first or second radio frequency signal, from the collector of the second bipolar transistor.

4. The power amplifying module according to claim 3, further comprising:

a third bipolar transistor connected in an emitter-follower connection manner to the base of the first bipolar transistor and configured to supply a bias to the first bipolar transistor based on a first bias control voltage applied to a base of the third bipolar transistor;

a fifth bipolar transistor connected in an emitter-follower connection manner to the base of the fourth bipolar transistor and configured to supply a bias to the fourth bipolar transistor based on a second bias control voltage applied to a base of the fifth bipolar transistor; and

a constant voltage circuit configured to generate the first constant voltage based on the first or second bias control voltage.

5. The power amplifying module according to claim 4, further comprising:

a first control terminal to which the first bias control voltage is input, the first control terminal connected to the base of the third bipolar transistor and to the constant voltage circuit; and

a second control terminal to which the second bias control voltage is input, the second control terminal connected to the base of the fifth bipolar transistor and to the constant voltage circuit.

6. The power amplifying module according to claim 1, further comprising:

a sixth bipolar transistor having a base to which the first amplified signal is input and an emitter grounded; and

a seventh bipolar transistor having a base to which a second constant voltage is applied, a collector to which a second power supply voltage is applied, the second power supply voltage adapted to vary in accordance with the amplitude of the first radio frequency signal, and an emitter connected to a collector of the sixth bipolar transistor, the seventh bipolar transistor configured to output a second amplified signal, obtained by amplifying the first amplified signal, from the collector of the seventh bipolar transistor.

7. The power amplifying module according to claim 2, further comprising:

a sixth bipolar transistor having a base to which the first amplified signal is input and an emitter grounded; and

a seventh bipolar transistor having a base to which a second constant voltage is applied, a collector to which a second power supply voltage is applied, the second power supply voltage adapted to vary in accordance with the amplitude of the first radio frequency signal, and an emitter connected to a collector of the sixth bipolar transistor, the seventh bipolar transistor configured to output a second amplified signal, obtained by amplifying the first amplified signal, from the collector of the seventh bipolar transistor.

8. The power amplifying module according to claim 3, further comprising:

a sixth bipolar transistor having a base to which the first amplified signal is input and an emitter grounded; and

a seventh bipolar transistor having a base to which a second constant voltage is applied, a collector to which a second power supply voltage is applied, the second power supply voltage adapted to vary in accordance with the amplitude of the first radio frequency signal or the second radio frequency signal, and an emitter connected to a collector of the sixth bipolar transistor, the seventh bipolar transistor configured to output a second amplified signal, obtained by amplifying the first amplified signal, from the collector of the seventh bipolar transistor.

9. The power amplifying module according to claim 4, further comprising:

a sixth bipolar transistor having a base to which the first amplified signal is input and an emitter grounded; and

a seventh bipolar transistor having a base to which a second constant voltage is applied, a collector to which a second power supply voltage is applied, the second power supply voltage adapted to vary in accordance with the amplitude of the first radio frequency signal or the second radio frequency signal, and an emitter connected to a collector of the sixth bipolar transistor, the seventh bipolar transistor configured to output a second amplified signal, obtained by amplifying the first amplified signal, from the collector of the seventh bipolar transistor.

10. The power amplifying module according to claim 4, further comprising:

a sixth bipolar transistor having a base to which the first amplified signal is input and an emitter grounded; and

a seventh bipolar transistor having a base to which a second constant voltage is applied, a collector to which a second power supply voltage is applied, the second power supply voltage adapted to vary in accordance with the amplitude of the first radio frequency signal or the second radio frequency signal, and an emitter connected to a collector of the sixth bipolar transistor, the seventh bipolar transistor configured to output a second amplified signal, obtained by amplifying the first amplified signal, from the collector of the seventh bipolar transistor.