US20020125954A1 - High-frequency amplifier circuit having a directly-connected bias circuit - Google Patents
High-frequency amplifier circuit having a directly-connected bias circuit Download PDFInfo
- Publication number
- US20020125954A1 US20020125954A1 US09/801,623 US80162301A US2002125954A1 US 20020125954 A1 US20020125954 A1 US 20020125954A1 US 80162301 A US80162301 A US 80162301A US 2002125954 A1 US2002125954 A1 US 2002125954A1
- Authority
- US
- United States
- Prior art keywords
- transistor
- bias
- circuit
- inductor
- frequency amplifier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000000694 effects Effects 0.000 abstract description 5
- 230000003071 parasitic effect Effects 0.000 description 5
- 238000004891 communication Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000005094 computer simulation Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/30—Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters
- H03F1/302—Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters in bipolar transistor amplifiers
Definitions
- the invention is in the field of transistor amplifier circuits, and relates more particularly to high-frequency amplifier circuits and bias circuits for such amplifier circuits.
- the output stage is typically a bipolar transistor connected in a common-emitter configuration, biased with either a voltage source or a current source providing a bias signal at the base of the output stage transistor.
- a straightforward way of biasing the output stage is to use a current-mirror circuit where the output stage is part of the current-mirror circuit.
- the quiescent DC current in the output stage can be directly controlled by a constant current in the current-mirror circuit.
- the bias of the amplifying transistor is provided by the current-mirror circuit through a resistor.
- the use of a resistor results in an increase in power loss in the circuit. This loss may be quite significant when a large current flows through the resistor.
- a new high-frequency amplifier circuit which includes an amplifying transistor and a bias circuit directly connected to the amplifying transistor.
- the bias circuit includes a bias transistor having a control terminal and an inductor coupled to the control terminal, with the bias transistor also having an output terminal directly connected to the amplifying transistor.
- a resistor is connected in series with the inductor coupled to the control terminal of the bias transistor, and the resistor and inductor are coupled between the control terminal and a power supply terminal.
- an additional transistor having a control terminal connected to the output terminal of the bias transistor and an output terminal connected to the control terminal of the bias transistor.
- High-frequency amplifier circuits in accordance with the present invention offer a significant improvement in that mismatch effects and power losses due to parasitic resistance are minimized and the connection of an external component such as an inductor is simplified.
- FIGURE shows a simplified schematic diagram of a high-frequency amplifier circuit in accordance with the invention.
- a simplified schematic diagram of a high-frequency amplifier circuit 1 is shown in the single FIGURE of the drawing.
- the amplifier circuit 1 includes an amplifying transistor 2 and a bias circuit 3 having a bias transistor 4 which has its emitter directly connected to the base of the amplifying transistor 2 .
- the bias circuit 3 also includes an additional transistor 6 having its collector connected to the base of transistor 4 and its base connected to the emitter of transistor 4 .
- transistor 6 is configured in a common-emitter mode and transistor 4 is configured in an emitter-follower mode of operation.
- An RF signal to be amplified is provided at terminal Vin through a coupling capacitor 8 to the base of transistor 2 , and an amplified output signal is taken from the collector of transistor 2 at terminal Vout, which is also coupled to a power supply terminal Vcc through an inductor 10 .
- the bias circuit 3 and amplifying transistor 2 are both coupled between the power supply terminal Vcc and a common terminal, shown here as a ground terminal gnd.
- an inductor 12 here connected in series with a resistor 14 , is coupled between Vcc and the base of bias transistor 4 , with the output of the bias circuit being directly connected to the amplifying transistor by a direct connection between the emitter of transistor 4 and the base of transistor 2 .
- bias circuits are typically coupled to the amplifying transistor by either a resistor or an inductor.
- these techniques can give rise to a number of disadvantages, including nonlinearity, mismatch, power loss, and the necessity for two extra bonding pads when an off-chip inductor is used.
- these problems are reduced or eliminated by directly connecting the bias circuit to the amplifying transistor, and providing the inductor 12 in series with the resistor 14 at a portion of the bias circuit remote from its connection to the amplifying transistor.
- the inductor 12 will have substantially no effect on the DC characteristics of the circuit, but will effectively reduce or eliminate the RPF loading effect of resistor 14 on the amplifying transistor 2 , a problem that would otherwise be particularly severe in circuits operating with a low power supply voltage.
- Operational advantages of the disclosed circuit include a more constant gain over a wider output range and improved linearity, advantages that are particularly important in applications such as wireless digital communication circuits.
- the inductor 12 can be provided on-chip or off-chip. If the inductor is provided off-chip, the invention offers the additional advantage of requiring less chip area and one less bonding pad, because only one internal bonding pad is required since one side of the inductor can be connected to Vcc outside the chip.
- the present invention provides a power amplifier circuit with a bias circuit which reduces or eliminates mismatch problems, power losses, external component connection complexity and performance degradation due to loading effects of prior-art bias circuits.
Abstract
Description
- The invention is in the field of transistor amplifier circuits, and relates more particularly to high-frequency amplifier circuits and bias circuits for such amplifier circuits.
- In high-frequency amplifier circuits, the output stage is typically a bipolar transistor connected in a common-emitter configuration, biased with either a voltage source or a current source providing a bias signal at the base of the output stage transistor.
- In IC technology, a straightforward way of biasing the output stage is to use a current-mirror circuit where the output stage is part of the current-mirror circuit. The quiescent DC current in the output stage can be directly controlled by a constant current in the current-mirror circuit. Typically, the bias of the amplifying transistor is provided by the current-mirror circuit through a resistor. However, the use of a resistor results in an increase in power loss in the circuit. This loss may be quite significant when a large current flows through the resistor.
- In order to reduce or eliminate this loss and provide RF isolation between the amplifying transistor and the biasing circuit, it has been suggested to use an inductor instead of a resistor to couple the bias circuit to the base of the RF amplifier transistor, as shown for example in U.S. Pat. No. 6.043,714. However, this is not a complete solution to the problem, since parasitic resistance from the inductor can still cause a power loss and furthermore, it may cause a mismatch between the transistor pair in the current-mirror circuit due to the parasitic resistance. In some IC amplifier designs, these problems can be reduced by employing an external inductor, having a lower parasitic resistance than that of an on-chip inductor, but with many circuits this will require two bonding pads for external connection. This is relatively undesirable, since bonding pads are always at a premium in IC design.
- Accordingly, it would be desirable to have a high-frequency amplifier circuit in which a bias circuit is employed which minimizes mismatch, minimizes power loss, and permits an external component connection, if required, to be done with only a single bonding pad.
- It is therefore an object of the invention to provide a high-frequency amplifier circuit in which a bias circuit is provided which minimizes mismatch, minimizes power loss due to parasitic resistance in an inductor, and permits an external component to be connected with only a single bonding pad.
- In accordance with the invention, these objects are achieved by a new high-frequency amplifier circuit which includes an amplifying transistor and a bias circuit directly connected to the amplifying transistor. The bias circuit includes a bias transistor having a control terminal and an inductor coupled to the control terminal, with the bias transistor also having an output terminal directly connected to the amplifying transistor.
- In a preferred embodiment of the invention, a resistor is connected in series with the inductor coupled to the control terminal of the bias transistor, and the resistor and inductor are coupled between the control terminal and a power supply terminal.
- In a further preferred embodiment of the invention, an additional transistor is provided having a control terminal connected to the output terminal of the bias transistor and an output terminal connected to the control terminal of the bias transistor.
- High-frequency amplifier circuits in accordance with the present invention offer a significant improvement in that mismatch effects and power losses due to parasitic resistance are minimized and the connection of an external component such as an inductor is simplified.
- These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments to be described hereinafter.
- The invention may be more completely understood with reference to the following description, to be read in conjunction with the accompanying drawing, in which the single FIGURE shows a simplified schematic diagram of a high-frequency amplifier circuit in accordance with the invention.
- A simplified schematic diagram of a high-frequency amplifier circuit1 is shown in the single FIGURE of the drawing. The amplifier circuit 1 includes an
amplifying transistor 2 and abias circuit 3 having a bias transistor 4 which has its emitter directly connected to the base of the amplifyingtransistor 2. Thebias circuit 3 also includes an additional transistor 6 having its collector connected to the base of transistor 4 and its base connected to the emitter of transistor 4. In the illustrative embodiment shown, transistor 6 is configured in a common-emitter mode and transistor 4 is configured in an emitter-follower mode of operation. - An RF signal to be amplified is provided at terminal Vin through a
coupling capacitor 8 to the base oftransistor 2, and an amplified output signal is taken from the collector oftransistor 2 at terminal Vout, which is also coupled to a power supply terminal Vcc through aninductor 10. Thebias circuit 3 and amplifyingtransistor 2 are both coupled between the power supply terminal Vcc and a common terminal, shown here as a ground terminal gnd. - In accordance with the invention, an
inductor 12, here connected in series with aresistor 14, is coupled between Vcc and the base of bias transistor 4, with the output of the bias circuit being directly connected to the amplifying transistor by a direct connection between the emitter of transistor 4 and the base oftransistor 2. - In the prior art, bias circuits are typically coupled to the amplifying transistor by either a resistor or an inductor. However, these techniques can give rise to a number of disadvantages, including nonlinearity, mismatch, power loss, and the necessity for two extra bonding pads when an off-chip inductor is used. In accordance with the present invention, these problems are reduced or eliminated by directly connecting the bias circuit to the amplifying transistor, and providing the
inductor 12 in series with theresistor 14 at a portion of the bias circuit remote from its connection to the amplifying transistor. In this configuration, theinductor 12 will have substantially no effect on the DC characteristics of the circuit, but will effectively reduce or eliminate the RPF loading effect ofresistor 14 on the amplifyingtransistor 2, a problem that would otherwise be particularly severe in circuits operating with a low power supply voltage. Operational advantages of the disclosed circuit include a more constant gain over a wider output range and improved linearity, advantages that are particularly important in applications such as wireless digital communication circuits. - Computer simulation results on a PCS-CDMA linear power amplifier indicate that the provision of
inductor 12 can result in an improvement in ACPR (Adjacent Channel Power Ratio) of about 8 dB with the power amplifier starting to saturate later when the inductor is provided. - It should be noted that the
inductor 12 can be provided on-chip or off-chip. If the inductor is provided off-chip, the invention offers the additional advantage of requiring less chip area and one less bonding pad, because only one internal bonding pad is required since one side of the inductor can be connected to Vcc outside the chip. - In this manner, the present invention provides a power amplifier circuit with a bias circuit which reduces or eliminates mismatch problems, power losses, external component connection complexity and performance degradation due to loading effects of prior-art bias circuits. These features translate into the performance advantages of a more constant gain over a wider output range and improved linearity in power amplifier applications such as wireless digital communications.
- While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention. Thus, for example, different types of transistors, bias circuits, and amplifying transistor circuits may be employed as appropriate, and alternations to the circuit configuration may be made to suit particular design requirements.
Claims (5)
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/801,623 US6456163B1 (en) | 2001-03-08 | 2001-03-08 | High-frequency amplifier circuit having a directly-connected bias circuit |
CN02800570.8A CN1633746A (en) | 2001-03-08 | 2002-02-18 | High-frequency amplifier circuit having a directly-connected bias circuit |
JP2002570393A JP2004521545A (en) | 2001-03-08 | 2002-02-18 | High frequency amplifier with direct bias circuit |
EP02712158A EP1371134A2 (en) | 2001-03-08 | 2002-02-18 | High-frequency amplifier circuit having a directly-connected bias circuit |
PCT/IB2002/000493 WO2002071596A2 (en) | 2001-03-08 | 2002-02-18 | High-frequency amplifier circuit having a directly-connected bias circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/801,623 US6456163B1 (en) | 2001-03-08 | 2001-03-08 | High-frequency amplifier circuit having a directly-connected bias circuit |
Publications (2)
Publication Number | Publication Date |
---|---|
US20020125954A1 true US20020125954A1 (en) | 2002-09-12 |
US6456163B1 US6456163B1 (en) | 2002-09-24 |
Family
ID=25181626
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/801,623 Expired - Fee Related US6456163B1 (en) | 2001-03-08 | 2001-03-08 | High-frequency amplifier circuit having a directly-connected bias circuit |
Country Status (5)
Country | Link |
---|---|
US (1) | US6456163B1 (en) |
EP (1) | EP1371134A2 (en) |
JP (1) | JP2004521545A (en) |
CN (1) | CN1633746A (en) |
WO (1) | WO2002071596A2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6531924B2 (en) * | 2001-04-18 | 2003-03-11 | Qualcomm Incorporated | Bias method and circuit for distortion reduction |
US20110025422A1 (en) * | 2009-07-30 | 2011-02-03 | Qualcomm Incorporated | Power amplifier bias current monitor and control mechanism |
CN103873156A (en) * | 2012-12-10 | 2014-06-18 | 北京普源精电科技有限公司 | Radio frequency measurement device with amplifier |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6417735B1 (en) * | 2001-12-07 | 2002-07-09 | Koninklijke Philips Electronics N.V. | Amplifier with bias compensation using a current mirror circuit |
US7057461B1 (en) * | 2003-03-19 | 2006-06-06 | Dynalinear Technologies, Inc. | Heterostructure bipolar transistor power amplifier module with dynamic voltage supply for improved efficiency |
JP2005020518A (en) * | 2003-06-27 | 2005-01-20 | Renesas Technology Corp | High frequency power amplifier circuit, electronic component for high frequency power amplification and its manufacturing method |
CN101394152B (en) * | 2007-09-20 | 2010-08-11 | 锐迪科科技有限公司 | Radio frequency power amplifier circuit |
JP2013106010A (en) * | 2011-11-16 | 2013-05-30 | Fujitsu Ltd | Driving circuit and optical transmitter |
US8854140B2 (en) * | 2012-12-19 | 2014-10-07 | Raytheon Company | Current mirror with saturated semiconductor resistor |
US10958222B2 (en) | 2018-06-15 | 2021-03-23 | Richwave Technology Corp. | Bias circuit |
TWI710210B (en) * | 2019-06-13 | 2020-11-11 | 立積電子股份有限公司 | Bias device |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2353173A1 (en) | 1976-04-13 | 1977-12-23 | Thomson Csf | TRANSISTORIZED POWER AMPLIFIER OPERATING IN CLASS AB AND ITS POLARIZATION CIRCUIT |
US4230999A (en) * | 1979-03-28 | 1980-10-28 | Rca Corporation | Oscillator incorporating negative impedance network having current mirror amplifier |
FI89110C (en) * | 1991-09-19 | 1993-08-10 | Nokia Mobile Phones Ltd | Power detector |
US5548248A (en) | 1995-07-30 | 1996-08-20 | Wang; Nan L. L. | RF amplifier circuit |
JP2720851B2 (en) | 1995-10-25 | 1998-03-04 | 日本電気株式会社 | Amplifier bias current control circuit |
US5670912A (en) | 1996-01-31 | 1997-09-23 | Motorola, Inc. | Variable supply biasing method and apparatus for an amplifier |
JP3327783B2 (en) * | 1996-08-30 | 2002-09-24 | シャープ株式会社 | Transistor power amplifier |
US5828269A (en) | 1996-12-05 | 1998-10-27 | Philips Electronics North America Corporation | High-frequency amplifier with high input impedance and high power efficiency |
US5909147A (en) | 1997-09-19 | 1999-06-01 | Honeywell Inc. | Amplifier having DC coupled gain stages |
JP3922773B2 (en) | 1997-11-27 | 2007-05-30 | 三菱電機株式会社 | Power amplifier |
US6326849B1 (en) * | 2000-09-28 | 2001-12-04 | Eic Corporation | Isolation circuit for use in RF amplifier bias circuit |
US6333677B1 (en) * | 2000-10-10 | 2001-12-25 | Rf Micro Devices, Inc. | Linear power amplifier bias circuit |
-
2001
- 2001-03-08 US US09/801,623 patent/US6456163B1/en not_active Expired - Fee Related
-
2002
- 2002-02-18 JP JP2002570393A patent/JP2004521545A/en not_active Withdrawn
- 2002-02-18 EP EP02712158A patent/EP1371134A2/en not_active Withdrawn
- 2002-02-18 WO PCT/IB2002/000493 patent/WO2002071596A2/en not_active Application Discontinuation
- 2002-02-18 CN CN02800570.8A patent/CN1633746A/en active Pending
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6531924B2 (en) * | 2001-04-18 | 2003-03-11 | Qualcomm Incorporated | Bias method and circuit for distortion reduction |
US20110025422A1 (en) * | 2009-07-30 | 2011-02-03 | Qualcomm Incorporated | Power amplifier bias current monitor and control mechanism |
US8890617B2 (en) | 2009-07-30 | 2014-11-18 | Qualcomm Incorporated | Bias current monitor and control mechanism for amplifiers |
US8970307B2 (en) | 2009-07-30 | 2015-03-03 | Qualcomm Incorporated | Bias current monitor and control mechanism for amplifiers |
US9166533B2 (en) * | 2009-07-30 | 2015-10-20 | Qualcomm Incorporated | Bias current monitor and control mechanism for amplifiers |
CN103873156A (en) * | 2012-12-10 | 2014-06-18 | 北京普源精电科技有限公司 | Radio frequency measurement device with amplifier |
Also Published As
Publication number | Publication date |
---|---|
EP1371134A2 (en) | 2003-12-17 |
WO2002071596A2 (en) | 2002-09-12 |
CN1633746A (en) | 2005-06-29 |
WO2002071596A3 (en) | 2003-10-09 |
JP2004521545A (en) | 2004-07-15 |
US6456163B1 (en) | 2002-09-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6778016B2 (en) | Simple self-biased cascode amplifier circuit | |
US6946913B2 (en) | High frequency amplifier circuit | |
US6417735B1 (en) | Amplifier with bias compensation using a current mirror circuit | |
US6414553B1 (en) | Power amplifier having a cascode current-mirror self-bias boosting circuit | |
US6492875B2 (en) | Self-boosting circuit for a power amplifier | |
US6791418B2 (en) | Capacitor coupled dynamic bias boosting circuit for a power amplifier | |
US7439805B1 (en) | Enhancement-depletion Darlington device | |
JP3631426B2 (en) | High power amplifier | |
US7619482B1 (en) | Compact low voltage low noise amplifier | |
US20020079971A1 (en) | Compact cascode radio frequency CMOS power amplifier | |
US7688133B2 (en) | Power amplifier | |
US7872532B2 (en) | High-frequency power amplifier and communication device | |
US6456163B1 (en) | High-frequency amplifier circuit having a directly-connected bias circuit | |
US5844443A (en) | Linear high-frequency amplifier with high input impedance and high power efficiency | |
US6417734B1 (en) | High-frequency amplifier circuit with negative impedance cancellation | |
US20040201421A1 (en) | Apparatus, methods and articles of manufacture for power amplifier control in a communication system | |
US20030201827A1 (en) | High frequency power amplifier module | |
JP2006093906A (en) | High-frequency power amplifier | |
US6593814B2 (en) | Amplifier circuit with protective device | |
KR20050122113A (en) | A low noise amplifier for low-power ultra-wideband receivers |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: KONINKLIJKE PHILIPS ELECTRONICS N.V., NETHERLANDS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LUO, SIFEN;SOWLATI, TIRDAD;REEL/FRAME:011685/0813 Effective date: 20010226 |
|
AS | Assignment |
Owner name: KONINKLIJKE PHILIPS ELECTRONICS N.V., NETHERLANDS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:PHILIPS ELECTRONICS NORTH AMERICA CORPORATION;REEL/FRAME:013174/0968 Effective date: 20020717 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20060924 |