MXPA97000907A - Efficient amplifier of semiconductor complementary metal oxide radio frequency with transductance aument - Google Patents
Efficient amplifier of semiconductor complementary metal oxide radio frequency with transductance aumentInfo
- Publication number
- MXPA97000907A MXPA97000907A MXPA/A/1997/000907A MX9700907A MXPA97000907A MX PA97000907 A MXPA97000907 A MX PA97000907A MX 9700907 A MX9700907 A MX 9700907A MX PA97000907 A MXPA97000907 A MX PA97000907A
- Authority
- MX
- Mexico
- Prior art keywords
- active device
- current
- anode
- coupled
- active
- Prior art date
Links
- 239000004065 semiconductor Substances 0.000 title claims description 6
- 229910044991 metal oxide Inorganic materials 0.000 title claims description 4
- 150000004706 metal oxides Chemical class 0.000 title claims description 4
- 230000000295 complement effect Effects 0.000 title description 2
- 239000003990 capacitor Substances 0.000 claims description 8
- 230000010287 polarization Effects 0.000 description 12
- 238000000034 method Methods 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 101150110671 AHT1 gene Proteins 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000036039 immunity Effects 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Abstract
An (integrated circuit) of RF (radio frequency) having improved transconductance, comprising a first active device of a first type of coding having a commutator or gate, anode or drain cathode or source, and a second active device of a second equipment that has a commutator, ano anode and a cathode. The second active device coupled in series are the first active device. The switch of the first device is coupled to the switch of the second active device. A current reuse circuit is coupled with the first active device and the second active device, in which the current flows from the anode so that the first active device is reused in the second active device. So the transconductance is increased without increasing the use of current and without an increase in noise.
Description
EFFICIENT AMPLIFIER OF SEMOQDUCTOR O ^ EMEOTARY OF
METAL RADIO OXIDE FRECOENCE WITH TRANSTttCTANgTA ATJMBMTADA
CAMPQ DE LA PWENCIQ
This invention relates to the field of MOS amplifiers (metal oxide semiconductor), and more particularly to the field of MOS amplifiers having improved transconductance.
AHT1 P, Rfl PB THE INVBWCigW
The demand for portable wireless communication systems increases the goal over portable RF (radio frequency) transceivers. Wireless communications include cellular systems, satellite systems, radar and other systems that usually use a receiver with low noise. Considerable effort has been expended in developing more sensitive receptors. Transistor amplifiers have improved steadily, with emphasis on the frequency of increased operation. Along with the low noise RF amplifier, a balanced mixer is often used
REF: 23790 to convert from RF to IF (intermediate frequency). Balanced operations provide approximately 20 dB of immunity with respect to amplitude noise in the local oscillator signal. The intermediate frequencies of 30 to 30 MHz are typical, as are the intermediate frequency noise quantities of 1.5 to 2 dB for the IF preamplifier. The CMOS (thin oxide metal semiconductor complementary semiconductor) process technologies provide potential for applications in IC (integrated circuits) for RF. When designing an RF amplifier, the potential for low energy operation is one of the attractive attributes of CMOS technology. A typical CMOS circuit application can provide very low standby power. Current flows in the circuit only when a state transition occurs. For a n-channel device, the current carriers are electrons, while for a p-channel device the carriers are hollow. In a MOS transistor there are four separate regions or terminals: cathode or source, anode or drain, commutator or gate and substrate. For normal operation, the cathode, anode and switch voltages measured with respect to the substrate are positive for a n-channel device, and negative for a p-channel device.
Therefore, there is a need for CMOS transceivers that use low-cost, energy-efficient IC implementations for front-end circuits.
In accordance with the present invention, an IC for RF having improved transconductance is provided. The device comprises a first active device of a first type of conductance having a commutator, an anode and a cathode and a second active device of a second type of conductance having a commutator, an anode and a cathode. The second active device is coupled in series with the first active device. The switch of the first active device is coupled with the switch of the second active device. A current reuse circuit is coupled with the first active device and the second active device, in which the current flows from the anode of the first active device and is used in the second active device. Therefore, the transconductance is increased without increased current utilization and without increasing noise. An LA Cl (low noise amplifier) for RF that has improved transconductance and an RF mixer having improved transconductance is also described in accordance with the present invention.
BRIEF DESCRIPTION OF THE DIBB3
A more complete understanding of the present invention can be obtained by considering the present description together with the drawings in which: Figure 1 is a schematic diagram of a two-stage LNA for RF according to the present invention; Figure 2 is a schematic diagram of an RF mixer according to the present invention; Figure 3 is a graph of the magnitudes of Figure 4 is a graph of the IF output spectrum of the measured IC mixer.
\? T? PK Vfiftaf
Although the present invention is particularly suitable for use with a 900 MHz CMOS low noise amplifier (LNA) and a mixer, and will be described with respect to this application, the methods and apparatus described herein can be applied to other MOS circuits that require transconductance without increased energy consumption. With reference to Figure 1, a scheme of two LNAs for two-stage RF is shown, according to the present invention. An LNA for RF comprises a first stage 10 and a second stage 20. Similar components in the second stage are numbered the same as the components in the first stage, since the two stages operate in a similar manner. The first stage 10 consists of 3 nMOS, M2, M4 and M5 devices, 4 pMOS devices M1 # M3, M6 and M7, a resistor Rx, capacitors CB and Cx, and a current source IB1. The switch devices M2 and x are usually coupled and are known as VA voltage. The source of M2 and the source IB1 of current are coupled to a voltage supply VDD. The anode of M2 is coupled with the output circuit Vo? T ?, the anode of Mx and one side of Rx. The capacitor CB is coupled between the cathode and the anode of M3. The cathode of M3 is coupled to The anode of M3 is coupled to the cathode of M1. The second side of Rx is coupled to the M4 switch. Capacitor Cx is coupled to the switch from M4 to V ^. The output of the current source IB1 is coupled to the cathode of M4 and the cathode of Ms. The anode of M4 is coupled to the anode of M6 and the commutator of M6. The cathode of M6 is coupled to V ^. The anode of M5 is coupled to the anode of M7 and to the M7 commutator. The M3 switch is coupled to the M7 switch.
The external networks Ns and NL are coupled with the input of LNA and the output ports at 50O respectively. The LNA uses a cascade connection of two transconductance amplifier circuits. One advantage of the two circuit design is that it improves the reverse insulation of the LNA compared to the design of a single circuit. Another advantage is that uncoupling the input and output ports simplifies the coupling. An RF signal is applied to the VRF, which activates the MOS Mx and M2 switches in the first circuit. Since an external image reject filter is usually used between the LNA output and the RF input of the mixer, the LNA output is able to activate a load resistance RL of 50Q. Since the topologies of the first and second circuits are identical, only the operation of the first circuit (single circuit) is described herein. Again with reference to Figure 1, the Mx and M2 devices are configured so that the transconductance of the circuit is gm = gml + gm2, where gml is the transconductance of Mx and g ^ is the transconductance of M2. The CB capacitor diverts the source of Mx to ground at high frequencies. Since the anode current of Mx is reused in M2, gm is increased without increasing the current consumption, in contrast to a common source amplifier, consisting of x or M2 only. A polarization feedback amplifier sets the output voltage of V0UT1 of the circuit to the bias reference VB1. The devices M3, M4, M5, Ms and M7 of bias current regulated in the Mx and M2 devices. The reference polarization IREF and the mirror current which is constituted by the devices M8 and M2 establishes the desired polarization current in the Mx and M2 devices. The polarization feedback cycle is completed with a low pass filter consisting of Rx and Cx. The low pass filter provides the output voltage of VX1 from V0OT1. The low frequency pole that contributes through the filter dominates the transmission of the polarization feedback amplifier cycle to obtain a high phase margin for the loop. The direct coupling between the output of the first circuit and the input of the second circuit is used. The reference polarization VB1 sets the output voltage of V00T1 for the first circuit and therefore sets the input voltage of the second circuit, determined as the polarization current of the second circuit. The polarization feedback amplifier of the second circuit establishes the output voltage of V0UT2 for bias reference VB2. When VA is the input voltage of the first circuit determined by IREF VB1 = VB2 = VA. The RB and RX resistors are chosen large enough to avoid a significant input and output load. With reference to Figure 2, a schematic of a mixer according to the present invention is shown. The mixer 30 is made up of 4 nMOS devices M13, M14, M19 and M20 / 5 pMOS devices Mn M12, M15, M17 and M21, resistors RX1, RX2, RB1 and RB2, the capacitor CX and the current sources IB and IREF. The M1X switch is coupled to the switch of M14 and to VL01. The switch of M13 is coupled to the switch of M2 and VL02. The cathode of M16, the cathode of Mlβ and the source of current IB are coupled to a voltage supply VDD. The switch of M16 is coupled to VREF1. The M18 switch is coupled to the M18 anode. The current cathode IREF is coupled between the anode of M18 and the voltage supply V ^. Resistor RB1 is coupled between the M16 switch and the M18 switch. The anode of M16 is coupled between the cathode of M13 and the cathode of M14. The anode of M13 is coupled to the anode of Mn. The anode of M14 is coupled to the anode of M12. The cathode of MX1 and the cathode of M12 are coupled to the anode of M15. The anode of M1S is coupled to V ^ RX1 is coupled between the anode of M14 and the M19 switch. The voltage on the M19 switch is called VX. RX2 is coupled between the M1X anode and the M19 commutator. Cx is coupled between the switch of M19 and V ^. The anode of M1X is coupled to V0UT2. The anode of M14 is coupled to V0UT1. The current cathode is coupled to the M19 cathode and the M20 cathode. The anode of M19 is coupled to the anode of M21 and to the M21 switch. The anode of M20 is coupled to the anode of M17 and to the switch of M17. RB2 is coupled between the M15 switch and the M17 switch. The cathode of M17, the cathode of M21 and the cathode of M15 are coupled to VGND. The external networks Ns match the RF port of the mixer at 50Q. The RF input is applied in VRF, activating VRF1 and VRF2, and in turn, switches M15 and M16, in phase. Referring again to Figure 2, devices M1S and M16 are configured as a transconductance amplifier in which gm = gml5 + gml6, where gml5 is the transconductance of M15 and gml6 is the transconductance of M16. The mixing amplifier uses the design principle used for the LNA circuits so that gm is increased while the anode current is reused, therefore an increased current consumption is avoided to increase gm. The cross-coupled devices Mu, M12, M13 and M14 constitute the main mixing cell which is activated by the inputs of the differential local oscillator (LO) V ^ and VL02. The anode currents of the M1S and M16 devices are regulated through the M1X and M13 devices or through the M12 and M14 devices, as a function of the LO phase.
When a VRF input is applied, the anode currents of Mi5 and M? E differ in gMVRF. This difference in current is then used to produce alternating current through a mixing cell which results in the desired IF current at the output ports V0UT1 and V0UT2 of the mixer. The outputs of the high impedance mixer are capable of driving an external high impedance IF filter. The polarization of the mixer is similar to that used for the LNA circuits. A feedback amplifier usually sets the common mode output level of the mixer, Vx, with the reference polarization VB. A differential pair and current mirror are constituted by MOS devices M15, M17, M19, M20 and M21, which regulate the polarization current in the mixing cell. The reference polarization IREF and a mirror current consisting of the MOS Mß and M16 devices establish the desired bias current in the mixing cell. A low pass filter completes the feedback loop. The low pass filter consists of RX1 # RX2 and Cx. This provides the common mode level Vx from outputs V00T1 and voot2- Resistors RB1, RB2, RX1 and RX2 are selected large enough to avoid a significant input and output load.
With reference to figure 3, a graph of the measured front and rear gain magnitudes of LNA is shown, | S21 | and | S12 |, respectively. With reference to figure 4, a graph of the IF output spectrum of the mixer measured when mixing two RF input tones at 899.5 Mhz and 900.5 Mhz with a frequency of LO at 1 Ghz is shown. The RF energy level is 29 dBm for each tone. The LO energy level is 0 dBm. The designs of the LNA and the mixer use external coupling capacitors at the input and output ports. The manufactured devices are measured in TQFP packages and manufactured in a CMOS process of 0.5 μm. The active area of the LNA IC is 0.7 mm x 0.4 mm. The active area of the LNA IC mixer is 0.7 mm x 0.2 mm. Numerous modifications and alternative embodiments of the invention will be apparent to those skilled in the art in light of the foregoing description. Accordingly, this description should be considered as illustrative only and for the purpose of describing to those skilled in the art the best way of carrying out the invention. The details of the structure may vary substantially without departing from the spirit of the invention and the exclusive use of all modifications which fall within the scope of the appended claims is considered as reserved. It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates. Having described the invention as above, property is claimed as contained in the following:
Claims (20)
1. An IC (integrated circuit) of RF (radio frequency) having an improved transconductance, the device is characterized in that it comprises-. a first active device of a first type of conductance having a commutator or gate, an anode or drain and a cathode or 'source; a second active device of a second type of conductance having a switch, an anode and a cathode, the second active device is coupled in series with the first active device and the switch of the first active device is coupled with the switch of the second active device; a current reuse circuit is coupled to the first active device and to the second active device, wherein a current flowing from the anode of the first active device is reused in the second active device; so the transconductance is increased without increasing current usage and without an increase in noise.
2. The device according to claim 1, characterized in that the first active device is an nMOS device (metal oxide semiconductor).
3. The device according to claim 1, characterized in that the second active device is a pMOS device.
4. The device according to claim 1, characterized in that the current reuse circuit regulates the current in the first active device and in the second active device.
5. The device according to claim 1, characterized in that the current reuse circuit further comprises a mirror current and a bias reference current to establish a bias current for the first active device and for the second active device.
6. The device according to claim 1, characterized in that it additionally comprises a low pass filter coupled between the current reuse circuit and the anode of the first active device, and the anode of the second active device.
7. The device according to claim 1, characterized in that it additionally comprises a capacitor coupled from the cathode of the first active device to the first voltage potential.
8. An IC (integrated circuit) of LNA (low noise amplifier) for RF (radio frequency) having improved transconductance, the device is characterized in that it comprises; a first active device of a first type of conductance having a commutator or gate, an anode or drain and a cathode or source; a second active device of a second type of conductance having a switch, an anode and a source, the second active device is coupled in series with the first active device and the switch of the first active device is coupled with the switch of the second active device; a current reuse circuit is coupled with the first active device and the second active device, wherein the current flowing from the anode of the first active device is reused in the second active device; so the transconductance is increased without an increase in current usage and without an increase in noise.
9. The device according to claim 8, characterized in that the first active device is an nMOS device (metal oxide semiconductor).
10. The device according to claim 8, characterized in that the second active device is a pMOS device.
11. The device according to claim 8, characterized in that the current reuse circuit regulates the current in the first active device and in the second active device.
12. The device according to claim 8, characterized in that the current reuse circuit further comprises a mirror current and a bias reference current to establish a bias current for the first active device and for the second active device.
The device according to claim 8, characterized in that it additionally comprises a low pass filter coupled between the current reuse circuit and the anode of the first active device, and the anode of the second active device.
14. The device according to claim 8, characterized in that it additionally comprises a capacitor coupled from the source of the first active device to the first voltage potential.
15. An RF mixer having an improved transconductance, the device is characterized in that it comprises: a first active device of a first type of conductance having a commutator or gate, an anode or drain and a cathode or source; a second active device of a second type of conductance having a switch, an anode and a cathode, the second active device is coupled in series with the first active device, and the switch of the first active device is coupled with the switch of the second device active; a current reuse circuit is coupled to the first active device and the second active device, wherein a current flowing from the anode of the first active device is reused in the second active device; so the transconductance is increased without increasing the current utilization without an increase in noise.
16. The device according to claim 15, characterized in that the first active device is an nMOS device.
17. The device according to claim 15, characterized in that the second active device is a pMOS device.
18. The device according to claim 15, characterized in that the current reuse circuit regulates the current in the first active device and in the second active device.
19. The device according to claim 15, characterized in that the current reuse circuit additionally comprises a mirror current and a bias reference current to establish a bias current for the first active device and for the second active device.
20. The device according to claim 15, characterized in that it additionally comprises a low pass filter coupled between the current reuse circuit and the anode of the first active device, and the anode of the second active device.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/597,776 US5721500A (en) | 1996-02-07 | 1996-02-07 | Efficient CMOS amplifier with increased transconductance |
| US08597776 | 1996-02-07 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| MXPA97000907A true MXPA97000907A (en) | 1998-04-01 |
| MX9700907A MX9700907A (en) | 1998-04-30 |
Family
ID=24392881
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| MX9700907A MX9700907A (en) | 1996-02-07 | 1997-02-04 | An efficient rf cmos amplifier with increased transconductance. |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US5721500A (en) |
| EP (1) | EP0789450A3 (en) |
| JP (1) | JPH09232882A (en) |
| CA (1) | CA2193153C (en) |
| MX (1) | MX9700907A (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6175279B1 (en) | 1997-12-09 | 2001-01-16 | Qualcomm Incorporated | Amplifier with adjustable bias current |
| US6754478B1 (en) * | 1998-07-24 | 2004-06-22 | Gct Semiconductor, Inc. | CMOS low noise amplifier |
| GB2351195A (en) | 1999-06-10 | 2000-12-20 | Ericsson Telefon Ab L M | An MOS voltage to current converter with current to voltage output stage and MOS feedback |
| US6859652B2 (en) | 2000-08-02 | 2005-02-22 | Mobile Satellite Ventures, Lp | Integrated or autonomous system and method of satellite-terrestrial frequency reuse using signal attenuation and/or blockage, dynamic assignment of frequencies and/or hysteresis |
| AU8468801A (en) * | 2000-08-02 | 2002-02-13 | Mobiles Satellite Ventures Lp | Coordinated satellite-terrestrial frequency reuse |
| US7792488B2 (en) * | 2000-12-04 | 2010-09-07 | Atc Technologies, Llc | Systems and methods for transmitting electromagnetic energy over a wireless channel having sufficiently weak measured signal strength |
| FR2857798B1 (en) * | 2003-07-17 | 2005-12-02 | Commissariat Energie Atomique | LOW CONSUMPTION VOLTAGE AMPLIFIER. |
| US20050124311A1 (en) * | 2003-12-03 | 2005-06-09 | Farsheed Mahmoudi | Low-voltage low-power high-linearity active CMOS mixer |
| JP4103883B2 (en) * | 2004-11-08 | 2008-06-18 | セイコーエプソン株式会社 | Amplifier circuit |
| US7215201B2 (en) * | 2005-06-20 | 2007-05-08 | Texas Instruments Norway As | Integrated circuit having a low power, gain-enhanced, low noise amplifying circuit |
| CN101820251A (en) * | 2010-05-17 | 2010-09-01 | 北京大学 | Ultra-low power consumption low-noise amplifier structure and preparation method thereof |
| US8310308B1 (en) | 2011-05-31 | 2012-11-13 | Texas Instruments Incorporated | Wide bandwidth class C amplifier with common-mode feedback |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4335360A (en) * | 1979-11-23 | 1982-06-15 | Hoover Merle V | Class AB push-pull amplifiers |
| JPS5718106A (en) * | 1980-07-09 | 1982-01-29 | Nippon Gakki Seizo Kk | Direct-coupled amplifying circuit |
| JPS5748718U (en) * | 1980-09-04 | 1982-03-18 | ||
| US4797631A (en) * | 1987-11-24 | 1989-01-10 | Texas Instruments Incorporated | Folded cascode amplifier with rail-to-rail common-mode range |
| DD295443A5 (en) * | 1990-09-24 | 1991-10-31 | Zentrum Mikroelektronik Dresden Gmbh I. G.,De | CMOS operational amplifier |
| US5221910A (en) * | 1990-10-09 | 1993-06-22 | Sgs-Thomson Microelectronics S.A. | Single-pin amplifier in integrated circuit form |
| FR2667743A1 (en) * | 1990-10-09 | 1992-04-10 | Sgs Thomson Microelectronics | SINGLE-SPINDLE AMPLIFIER IN AN INTEGRATED CIRCUIT. |
| JPH07118618B2 (en) * | 1991-02-28 | 1995-12-18 | 菊水電子工業株式会社 | Negative feedback amplifier |
| US5351012A (en) * | 1993-04-02 | 1994-09-27 | Elantec, Inc. | Low input resistance current-mode feedback operational amplifier input stage |
| US5568093A (en) * | 1995-05-18 | 1996-10-22 | National Semiconductor Corporation | Efficient, high frequency, class A-B amplifier for translating low voltage clock signal levels to CMOS logic levels |
-
1996
- 1996-02-07 US US08/597,776 patent/US5721500A/en not_active Expired - Lifetime
- 1996-12-17 CA CA002193153A patent/CA2193153C/en not_active Expired - Fee Related
-
1997
- 1997-01-28 EP EP97300525A patent/EP0789450A3/en not_active Withdrawn
- 1997-02-04 MX MX9700907A patent/MX9700907A/en unknown
- 1997-02-07 JP JP9024197A patent/JPH09232882A/en active Pending
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