throbber
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`
`IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 56, NO. 5, MAY 2008
`
`Resistive-Feedback CMOS Low-Noise
`Amplifiers for Multiband Applications
`
`Bevin G. Perumana, Student Member, IEEE, Jing-Hong C. Zhan, Member, IEEE, Stewart S. Taylor, Fellow, IEEE,
`Brent R. Carlton, Member, IEEE, and Joy Laskar, Fellow, IEEE
`
`Fig. 1. Multiband receiver implementation using a multiband/wideband LNA.
`
`Fig. 2. Multiband receiver implementation using multiple narrowband LNAs.
`
`resistive-feedback CMOS
`compact
`Abstract—Extremely
`low-noise amplifiers (LNAs) are presented as a cost-effective
`inductors
`alternative to multiple narrowband LNAs using high-
`for multiband wireless applications. Limited linearity and high
`power consumption of the inductorless resistive-feedback LNAs
`are analyzed and circuit techniques are proposed to solve these
`issues. A 12-mW resistive-feedback LNA, based on current-reuse
`transconductance boosting is presented with a gain of 21 dB and
`a noise figure (NF) of 2.6 dB at 5 GHz. The LNA achieves an
`output third-order intercept point (IP3) of 12.3 dBm at 5 GHz by
`reducing loop-gain rolloff and by improving linearity of individual
`stages. The active die area of the LNA is only 0.012 mm2.
`A 9.2-mW tuned resistive-feedback LNA utilizing a single com-
`on-chip inductor is presented, showing an improved
`pact low-
`tradeoff between performance, power consumption, and die area.
`At 5.5 GHz, the fully integrated LNA achieves a measured gain
`of 24 dB, an NF of 2 dB, and an output IP3 of 21.5 dBm. The
`LNA draws 7.7 mA from the 1.2-V supply and has a 3-dB band-
`width of 3.94 GHz (4.04–7.98 GHz). The LNA occupies a die area
`of 0.022 mm2. Both LNAs are implemented in a 90-nm CMOS
`process and do not require any costly RF enhancement options.
`Index Terms—CMOS low-noise amplifier (LNA), feedback am-
`plifiers, multiband wireless receivers.
`
`I. INTRODUCTION
`
`LOW-NOISE amplifiers (LNAs) occupy a significant per-
`
`centage of the total die area in wireless front-ends today.
`This is because the performance of the LNA is dependent on the
`’s of the multiple on-chip inductors. Since the area require-
`ment of high-
`on-chip inductors is high, the die area occu-
`pied by the LNA is also high. Often, costly process steps are
`required to enhance the
`of the on-chip inductors to further
`improve the performance of RF circuits. The design of these
`circuits usually requires a higher number of simulation and veri-
`fication iterations. Cascode amplifiers with inductive source de-
`generation [1], the predominant LNA implementation used in
`
`Manuscript received September 1, 2007; revised January 18, 2008.
`B. G. Perumana was with the Communications Circuits Laboratory, Intel Cor-
`poration, Hillsboro, OR 97124 USA. He is now with the Georgia Electronic De-
`sign Center, School of Electrical and Computer Engineering, Georgia Institute
`of Technology, Atlanta, GA 30332 USA (e-mail: beving@ece.gatech.edu).
`J.-H. C. Zhan was with the Communications Circuits Laboratory, Intel Corpo-
`ration, Hillsboro, OR 97124 USA. He is now with the RF Division, MediaTek,
`HsinChu, 300 Taiwan, R.O.C.
`S. S. Taylor and B. R. Carlton are with the Communications Circuits Labo-
`ratory, Intel Corporation, Hillsboro, OR 97124 USA.
`J. Laskar is with the Georgia Electronic Design Center, School of Electrical
`and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332
`USA.
`Color versions of one or more of the figures in this paper are available online
`at http://ieeexplore.ieee.org.
`Digital Object Identifier 10.1109/TMTT.2008.920181
`
`inductors for
`CMOS wireless front-ends, require three high-
`achieving input impedance matching, high gain, and low noise
`figure (NF). In spite of the high die area requirements, cascode
`LNAs have been used extensively in narrowband wireless ap-
`plications because they provide high gain, low noise, and high
`linearity at relatively low power consumption. With the advent
`of multiple-input multiple-output (MIMO), multistandard, and
`multiband wireless systems; however, the use of the area inten-
`sive cascode LNAs is becoming increasingly expensive, leading
`to the pursuit of alternative LNA implementations.
`A multiband receiver can be implemented by using a single
`multiband or wideband LNA, as shown in Fig. 1. Cascode LNAs
`based on inductive source degeneration are not suitable for this
`implementation since it is extremely difficult to switch the three
`on-chip inductors to make the same cascode LNA work across
`all the required frequency bands without compromising perfor-
`mance. Multiband receivers can also be implemented by using
`multiple narrowband LNAs, each designed for a different fre-
`quency band, as shown in Fig. 2. If cascode LNAs with induc-
`tive degeneration are used for this implementation, the die area
`and cost will both be prohibitively high.
`Inductorless resistive-feedback CMOS LNAs [2]–[4] have
`been shown to be a viable option for implementing multiband
`receivers, as shown in Fig. 1. These circuits require very small
`die area and can be implemented in a digital CMOS process
`without any additional RF enhancements. Hence, this approach
`can potentially significantly reduce the cost of the wireless
`front-end implementation. Resistive-feedback LNAs achieve
`INTEL 1208
`
`0018-9480/$25.00 © 2008 IEEE
`
`

`

`PERUMANA et al.: RESISTIVE-FEEDBACK CMOS LNAs FOR MULTIBAND APPLICATIONS
`
`1219
`
`is the source resistance and
`the shunt–shunt feedback.
`is used for biasing along with dc blocking capacitors
`and
`. The equivalent small-signal model of
`the transimpedance amplifier is shown in Fig. 3(b), where
`represents the transconductance of
`.
`represents the
`. For frequencies well
`capacitance to ground at the gate of
`, the effect of
`can be neglected.
`below
`
`A. Voltage Gain
`Using the small-signal model in Fig. 3(b), the voltage gain of
`the amplifier can be derived as
`
`(1)
`
`Feedback analysis [10] can be done by opening the loop and
`and the feed-
`determining the open-loop transresistance gain
`, shown as follows:
`back factor
`
`The voltage gain given by feedback analysis is
`
`(2)
`
`(3)
`
`(4)
`
`The discrepancy between (1) and (4) is because the feedfor-
`is ignored in the feedback analysis. This
`ward path through
`.
`difference is negligible if
`
`B. Input Impedance Matching
`Shunt–shunt feedback reduces the input impedance of the
`amplifier by a factor of
`. The input resistance
`of the amplifier is given by
`
`(5)
`
`since
`(for reasons related to NF, which will ex-
`has to be
`plained later). For input impedance matching,
`. From (5), input matching is achieved with a
`equal to
`loop gain
`just below 1, which also ensures circuit sta-
`bility. Using (3), the open-loop transresistance gain has to be
`approximately equal to the value of the feedback resistance for
`achieving input impedance matching
`
`Input Impedance Match Condition:
`
`(6)
`
`C. NF
`The contribution of each noise source to the total output noise
`is evaluated. The NF is then calculated by evaluating the ratio of
`the total output noise to the output noise due to
`as follows:
`
`(7)
`
`Fig. 3. Simplified schematic and small-signal model of a shunt-shunt feedback
`amplifier.
`
`high gain and reasonably low NF [4]. However, novel circuit
`techniques are required to reduce power consumption and
`improve linearity.
`This paper presents an inductorless resistive-feedback LNA
`in which a current-reuse transconductance-boosting technique
`[5] is utilized to reduce the power consumption to 12 mW. The
`LNA has a gain of 21 dB and an NF of 2.6 dB at 5 GHz. The
`active die area of this circuit is only 0.012 mm . The combi-
`nation of small die area, broad bandwidth and moderate power
`consumption make this LNA architecture suitable for low-cost
`multistandard wireless front-ends, as shown in Fig. 1. By main-
`taining a moderate loop-gain across the frequency band and re-
`ducing the nonlinearities of individual stages, the LNA achieves
`an output third-order intercept point (IP3) of 12.3 dBm at 5 GHz.
`Techniques to further improve IP3 by nonlinearity cancellation
`[6]–[9] are also presented.
`A resistive-feedback cascode LNA using a single com-
`pact on-chip load inductor is presented next. It has a max-
`imum gain of 24.4 dB, and a 3-dB bandwidth of 3.94 GHz
`(4.04–7.98 GHz). At 5.5 GHz, the NF is 2 dB, and the output
`is not required to be
`IP3 is 21.5 dBm. Since the inductor
`high, the area of this LNA is only 0.022 mm . This makes it
`suitable for multiband receiver implementations, as shown in
`Fig. 2. This LNA can also be easily modified to operate across
`multiple frequency bands (as in Fig. 1) since the single low-
`tuned load can be switched to resonate at different frequencies.
`The gain,
`input
`impedance, NF, and linearity of resis-
`tive-feedback LNAs are discussed in Section II. Section III
`describes circuit techniques to improve linearity and lower
`power consumption. The design of the inductorless LNA
`with current-reuse transconductance boosting and the tuned
`inductor) are
`resistive-feedback LNA (using a compact low-
`described in Section III. The implementation details of these
`circuits are discussed in Section IV. The measurement results of
`both the LNAs are given in Section V along with performance
`comparison to other reported circuits. Finally, conclusions are
`presented in Section VI.
`
`II. RESISTIVE-FEEDBACK LNA THEORY
`
`Consider a simplified resistive-feedback amplifier, as shown
`represents the input transconductance device,
`in Fig. 3(a).
`repre-
`which could be a single transistor or a cascode pair.
`sents the load resistance including the output resistance of the
`is the resistor implementing
`input transconductance stage.
`
`

`

`1220
`
`IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 56, NO. 5, MAY 2008
`
`[11]. Equation (7)
`is the noise excess factor of
`where
`shows that having a large feedback resistance can lower the NF.
`requires a higher open-loop gain for input
`From (6), a higher
`matching, usually leading to higher power consumption.
`
`D. Linearity
`Consider a nonlinear amplifier modeled by the power series
`[12]
`
`(8)
`
`Negative feedback improves its input IP3 by the following
`factor:
`
`Fig. 4. Schematic of
`tive-feedback LNA.
`
`the current-reuse transconductance-boosting resis-
`
`(9)
`
`represent the
`, and
`,
`where
`close-loop and open-loop IP3, respectively. Equation (9) shows
`that linearity is not significantly improved by feedback at high
`frequencies if the open-loop gain of the amplifier rolls off [2].
`
`III. LOW-POWER HIGH-LINEARITY
`RESISTIVE-FEEDBACK LNAs
`As discussed in Section II, a high open-loop gain is required
`to simultaneously achieve low NF and good input matching.
`The open-loop bandwidth also has to be high to achieve high
`linearity at high frequencies. These requirements usually lead
`to high power consumptions in resistive-feedback LNAs [2],
`[4]. We now present circuit techniques to improve linearity and
`lower power consumption in resistive-feedback LNAs.
`
`A. Current-Reuse Resistive-Feedback LNA
`The schematic of the restive feedback LNA with current-
`reuse transconductance boosting is shown in Fig. 4. Cascode
`transistors
`and
`form the input transconductance stage.
`A significant portion of the bias current in
`is diverted away
`by transistor
`. This reduces the dc
`from the load resistor
`. Moreover, the transconductance gener-
`voltage drop across
`ated by
`adds to that of
`, increasing the effective
`of the
`and
`controls
`input stage. The current mirror formed by
`. The amplified
`the amount of current shunted away from
`signal is fed back to the input transconductance stage through
`and the source follower formed by
`,
`feedback resistor
`, and
`. The diode connected
`is used in the source fol-
`,
`, and
`. The
`lower to generate gate bias voltages for
`dc and ac feedback loops are thus combined, making it possible
`to remove the dc blocking capacitors required in earlier reports
`[4]. This reduces the total area requirement, and avoids loading
`of the source follower by the parasitic capacitance of the dc
`blocking capacitor to the substrate. The latter improves the LNA
`and
`,
`linearity. An additional source follower, formed by
`is incorporated to improve reverse isolation and output driving
`capability. As discussed in Section II, the linearity at high fre-
`quencies can be improved by increasing open-loop bandwidth.
`This is achieved by device sizing and reducing layout para-
`sitics as much as possible. The overall linearity of the LNA is
`
`improved by making each block of the LNA more linear. Re-
`moving the dc block capacitors reduces the loading of the source
`follower, making it more linear, as explained earlier. Resistors
`and
`replace active current mirrors, which are nonlinear
`and have greater capacitance.
`-enhanced cascode
`In all resistive-feedback LNAs with
`structure, the width/length (W/L) ratio of the cascode transistor
`is kept low to achieve a higher bandwidth. The cascode device
`also has a lower bias current than the input transistor so as to re-
`duce the voltage drop across the load resistor, as explained ear-
`lier. The lower W/L ratio and bias current makes the transcon-
`ductance of the common-gate cascode transistor significantly
`lower than the common-source input transistor. The gain of the
`common-source stage is the ratio of these transconductances.
`The high gain in the common-source input stage preceding the
`nonlinearity in the cascode stage
`cascode stage makes the
`limit the overall circuit linearity. This is because the IIP3 of
`is related to the IIP3 of the
`the combined stages
`, its gain
`, and the IIP3 of
`common-source stage
`by the following equation:
`the common-gate stage
`
`(10)
`
`Hence, significant improvement in linearity can be obtained
`if the nonlinearity of the cascode stage is reduced by nonlin-
`earity cancellation. This can be achieved by using derivative
`superposition [6], [13], as shown in Fig. 5(a). Here, the
`of the common-gate stage (
`) is cancelled
`by the
`of the subthreshold transistor
`. The measured
`-enhanced cascode LNA is plotted against
`input IP3 of the
`in Fig. 5(b). Though significant
`the gate voltage of
`improvements in IP3 have been demonstrated with derivative
`superposition at the cost of increased NF ( 0.6 dB) [9], such
`cancellation techniques may have potential issues in volume
`applications due to process and temperature variations.
`
`B. Tuned Resistive-Feedback LNA with a Compact
`Low- Load Inductor
`
`Linearity issues due to the high gain in the common-source
`stage preceding the common-gate cascode stage can be avoided
`by replacing the load resistance with a low-
`resonant load,
`
`

`

`PERUMANA et al.: RESISTIVE-FEEDBACK CMOS LNAs FOR MULTIBAND APPLICATIONS
`
`1221
`
`Fig. 5. Nonlinearity cancellation in a g -enhanced cascode LNA with deriva-
`tive superposition.
`
`Fig. 7. Schematic of the modified super source follower output buffer.
`
`shown in Fig. 1. The band-switching scheme enabling this
`implementation is shown in Fig. 6. The resonant frequency
`can be shifted by using the capacitors
`and
`and the
`and
`. At resonance, the load impedance is
`switches
`purely resistive and given by
`
`(11)
`
`Here,
`of the load inductor
`are the inductance and
`and
`. All the equations from Section II
`at the resonant frequency
`are still valid if
`is replaced by
`, and if
`represents
`the effective transconductance of the cascode stage.
`and
`are used to shift
`, the value of
`If the switches
`, given by (11), will not be the same in different frequency
`bands. Thus, the open-loop transimpedance gain ( ) given
`by (2), will also vary from one frequency band to another.
`To satisfy the input matching condition in (6) across all the
`will also have to
`frequency bands, the feedback resistance
`be switched, as shown in Fig. 6, using switches
`and
`.
`
`IV. IMPLEMENTATION OF THE RESISTIVE-FEEDBACK LNAs
`Both of the resistive-feedback LNAs are implemented in a
`90-nm seven-metal CMOS process. The only RF enhancement
`option used is the high-resistivity substrate under RF signal
`paths. All the capacitors were implemented as inter-digitated
`metal finger capacitors. Since the output impedance of the
`, a modified super source follower [4] was
`LNAs are not 50
`used to facilitate measurements. The schematic of this circuit is
`shown in Fig. 7.
`The current-reuse transconductance-boosting resistive-feed-
`back LNA draws 6.7 mA from the 1.8-V supply, thus consuming
`12 mW of power. The chip micrograph of this LNA is shown in
`Fig. 8. The chip is pad limited and the actual LNA dimensions
`are 40 m 310 m (Area: 0.012 mm ). This implementation
`is a very low-cost alternative to the conventional inductor-based
`circuits for multiband multistandard radios.
`The tuned resistive-feedback LNA has a power consump-
`tion of 9.2 mW, drawing 7.7 mA from the 1.2-V supply. Band
`switching is not implemented and the LNA is designed to op-
`erate in a single frequency band around 5.5 GHz. The chip mi-
`crograph of this circuit is shown in Fig. 9. The LNA dimensions
`are 155 m 145 m (Area: 0.022 mm ).
`
`Fig. 6. Schematic of the tuned resistive-feedback LNA utilizing a compact
`low-Q load inductor.
`
`using a compact on-chip inductor. The bias current of the cas-
`code device can be made equal to that of the input device be-
`cause the dc voltage drop across the resonant load is negligible.
`Since all the capacitance at the output node can be resonated out
`with the inductive load, it is not necessary to make the W/L ratio
`of the cascode device small.
`The schematic of a tuned resistive-feedback LNA is shown in
`is used as the common-source transcon-
`Fig. 6. Transistor
`ductance stage and
`is used as the cascode common-gate
`stage. A compact low- on-chip spiral inductor
`and the total
`capacitance at the output node form the resonant load. The par-
`and
`) to
`asitic capacitance of the dc block capacitors (
`substrate and the drain capacitance of
`can, therefore, be res-
`onated out along with the load capacitance at the output node.
`,
`, and
`form the shunt-shunt feed-
`Resistors
`and
`and resistor
`are used
`back path. Capacitors
`for biasing the cascode transistors.
`load inductor,
`Since this LNA utilizes only a single low-
`it can be made extremely compact. Hence, low-cost multiband
`receivers can be implemented by using multiple tuned resistive-
`feedback LNAs each designed for a different frequency band,
`as shown in Fig. 2.
`This circuit can be easily modified to operate across different
`frequency bands for the multiband receiver implementation
`
`

`

`1222
`
`IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 56, NO. 5, MAY 2008
`
`Fig. 8. Chip micrograph of the current-reuse transconductance-boosting resis-
`tive-feedback LNA.
`
`Fig. 10. Measured and simulated gain of the current-reuse transconductance-
`boosting resistive-feedback LNA and output buffer.
`
`Fig. 9. Chip micrograph of the tuned resistive-feedback LNA.
`
`V. MEASUREMENT RESULTS
`
`The measurements for both of the resistive-feedback LNAs
`were performed with on-wafer probing. Standalone output
`buffers were measured to deembed their effect on the measure-
`ment results of the LNAs.
`
`A. Measurement Results of the Current-Reuse
`Resistive-Feedback LNA
`
`The standalone output buffer used with the current-reuse
`transconductance boosting LNA has an insertion loss of 7 dB.
`Its input IP3 is 15.6 dBm at 5.8 GHz, 18 dBm at 5 GHz, and
`higher at lower frequencies. The buffer NF is 10 dB, including
`the noise added by a 50-
`resistor added at the input for
`impedance matching.
`The measured and simulated gain of the LNA and output
`buffer is shown in Fig. 10. Also plotted in Fig. 10 are the buffer
`loss and the deembedded LNA gain. The gain falls from 22 dB
`at low frequencies to 21 dB at 5 GHz. The 3-dB bandwidth is
`7.5 GHz.
`The measured and simulated input matching of the LNA are
`10 dB at 5 GHz and better at lower
`plotted in Fig. 11. It is
`frequencies. The measured NF is plotted against frequency
`in Fig. 12. The NF is 2.6 dB at 5 GHz and varies between
`2.3–2.9 dB from 500 MHz to 7 GHz. The 1.5-dB increase in
`gain in the measured results is due to slightly higher values
`and
`. This increase in gain leads to improved input
`for
`matching and noise performance compared to the simulated
`results.
`
`Fig. 11. Measured and simulated input matching of the resistive-feedback
`LNA.
`
`Fig. 12. Measured and simulated NF of the LNA and output buffer.
`
`The input IP3 of the LNA is plotted in Fig. 13 after deembed-
`ding the effects of the output buffer. It varies from 2.3 dBm at
`500 MHz to 8.8 dBm at 5.8 GHz. The degradation of linearity
`
`

`

`PERUMANA et al.: RESISTIVE-FEEDBACK CMOS LNAs FOR MULTIBAND APPLICATIONS
`
`1223
`
`Fig. 13. Measured input IP3 of the current-reuse transconductance-boosting
`LNA.
`
`Fig. 15. Measured and simulated input matching of the tuned LNA.
`
`Fig. 14. Measured and simulated gain of the tuned resistive-feedback LNA and
`output buffer.
`
`with frequency is due to the loop gain rolloff with frequency, as
`explained earlier.
`
`B. Measurement Results of the Tuned Resistive-Feedback LNA
`The standalone output buffer used with the tuned resistive-
`feedback LNA is similar to the one used with the current-reuse
`LNA and has a loss of 8 dB, and an NF of 9.8 dB (including the
`resistor at the input). The output buffer
`noise added by the 50-
`has an input 1-dB compression point of 6.5 dBm and an input
`IP3 of 18 dBm at 5.5 GHz.
`The measured and simulated gain of the LNA and output
`buffer is plotted in Fig. 14. The buffer loss and the deembedded
`gain of the LNA without the buffer are also plotted in Fig. 14.
`The LNA has a maximum gain of 24.4 dB and a 3-dB band-
`width of 3.94 GHz from 4.04 to 7.98 GHz. The measured input
`matching is plotted in Fig. 15. The input matching is better than
`10 dB from 5 to 6.85 GHz.
`Fig. 16 shows the measured and simulated NF of the tuned
`resistive-feedback LNA and the output buffer. The deembedded
`NF of the LNA without the output buffer is also plotted. The
`tuned resistive-feedback LNA has an NF of approximately 2 dB
`between 4–6 GHz.
`The IP3 of the LNA and output buffer is plotted in Fig. 17.
`The input IP3 of the tuned resistive-feedback LNA and output
`
`Fig. 16. Measured and simulated NF of the tuned resistive-feedback LNA and
`output buffer.
`
`Fig. 17.
`
`Input IP3 of the tuned resistive-feedback LNA.
`
`buffer is 7.7 dBm at 5.5 GHz. The IIP3 of the LNA is found to
`2.6 dBm after deembedding the output buffer nonlinearity
`be
`using the IIP3 of the standalone buffer (18 dBm) and the gain
`of the LNA (24.1 dB). Therefore, the output IP3 of the LNA
`is 21.5 dBm. The measured input 1-dB compression point of
`18 dBm at 5.5 GHz. The input 1-dB
`the LNA and buffer is
`compression point of the LNA without the output buffer is found
`7.2 dBm after deembedding.
`to be
`
`

`

`1224
`
`IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 56, NO. 5, MAY 2008
`
`TABLE I
`WIDEBAND LNA PERFORMANCE COMPARISON
`
`consumption makes this LNA architecture a compelling choice
`for low-cost multistandard wireless front-ends.
`
`ACKNOWLEDGMENT
`The authors would like to thank the following colleagues
`at the Communication Circuit Laboratory, Intel Corporation,
`Hillsboro, OR: D. Steele for layout assistance; R. Bishop for
`measurement setup, J. S. Duster
`for useful discussions; and
`K. Soumyanath for support and encouragement.
`
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`dBm output-IP3 resistive feedback LNA in 90-nm CMOS,” presented
`at the ESSCIRC, 2007.
`[10] P. R. Gray, P. J. Hurst, S. H. Lewis, and R. G. Meyer, Analysis and
`Design of Analog Integrated Circuits, 4th ed. New York: Wiley, 2001.
`[11] Y. Cui, G. Niu, Y. Li, S. S. Taylor, Q. Liang, and J. D. Cressler, “On
`the excess noise factors and noise parameter equations for RF CMOS,”
`in Silicon Monolithic Integr. Circuits RF Syst. Top. Meeting, Jan. 2007,
`pp. 40–43.
`[12] W. Sansen, “Distortion in elementary transistor circuits,” IEEE Trans.
`Circuits Syst. II, Analog, Digit. Signal Process., vol. 46, no. 3, pp.
`315–325, Mar. 1999.
`[13] T. W. Kim, B. Kim, and K. Lee, “Highly linear receiver front-end
`adopting MOSFET transconductance linearization by multiple gated
`transistors,” IEEE J. Solid-State Circuits, vol. 39, no. 1, pp. 223–229,
`Jan. 2004.
`[14] J. Borremans, P. Wambacq, and D. Linten, “An ESD-protected
`DC-to-6 GHz 9.7 mW LNA in 90 nm digital CMOS,” in IEEE ISSCC
`Tech. Dig., 2007, pp. 422–423.
`[15] M. T. Reiha, J. R. Long, and J. J. Pekarik, “A 1.2 V reactive-feedback
`3.1–10.6 GHz ultrawideband low-noise amplifier in 0.13 m CMOS,”
`in Proc. IEEE RFIC Symp., 2006, pp. 41–44.
`[16] R. Salerno, M. Tiebout, H. Paule, M. Streibl, C. Sandner, and K. Kropf,
`“ESD-protected CMOS 3–5 GHz wideband LNA+PGA design for
`UWB,” in Proc. ESSCIRC, 2005, pp. 219–222.
`
`Bevin G. Perumana (S’04) was born in Kerala,
`India, in 1980. He received the B.Tech. degree in
`electrical engineering from the Indian Institute of
`Technology, Kharagpur, India, in 2002, the M.S. de-
`gree in electrical engineering from Georgia Institute
`of Technology, Atlanta, in 2005, and is currently
`working toward the Ph.D. degree in electrical and
`computer engineering at the Georgia Institute of
`Technology. His doctoral dissertation concerns
`low-power CMOS front-ends for wireless personal
`area networks.
`
`The performance of the two resistive-feedback LNAs are
`tabulated and compared with others reported in Table I. The
`current-reuse
`transconductance-boosting resistive-feedback
`LNA provides comparable performance at lower power con-
`sumption while occupying very small die area. The tuned
`resistive-feedback LNA, though requiring slightly larger die
`area than the inductorless LNA, provides very high linearity,
`low noise, and high gain while dissipating low power. This
`LNA presents a much improved tradeoff between performance,
`power consumption, and cost, especially for multiband multi-
`standard wireless receivers.
`
`VI. CONCLUSION
`
`Extremely compact LNA circuits based on resistive feedback
`are presented as a cost-effective alternative to multiple tuned
`inductors for multiband wireless
`LNAs requiring many high-
`applications. The relationships between the feedback resistance,
`NF, input matching, and open-loop gain are presented. The ef-
`fect of the open-loop bandwidth on the close-loop linearity is
`also explained. A current-reuse transconductance boosting tech-
`nique is used to reduce the power consumption in a resistive-
`feedback LNA to 12 mW. The inductorless LNA achieves a gain
`of 21 dB and an NF of 2.6 dB at 5 GHz. The rolloff of loop
`gain and the nonlinearities in the feedback loop are reduced to
`improve the output IP3 to 12.3 dBm at 5 GHz. The active die
`area of this LNA is only 0.012 mm . A tuned resistive-feed-
`back LNA, using a compact resonant load, is also presented.
`It achieves a maximum gain of 24.4 dB and a 3-dB bandwidth
`on-chip inductor and con-
`of 3.94 GHz using a single low-
`suming 9.2 mW of power. The LNA has an active die area of
`0.022 mm . The NF of the tuned resistive-feedback LNA is ap-
`proximately 2 dB between 4–6 GHz. At 5.5 GHz, the LNA has
`an output IP3 of 21.5 dBm. The combination of high linearity,
`low NF, high broadband gain, small die area, and low power
`
`

`

`PERUMANA et al.: RESISTIVE-FEEDBACK CMOS LNAs FOR MULTIBAND APPLICATIONS
`
`1225
`
`From 2002 to 2003, he was a Research Consultant with the Advanced Very
`Large Scale Integration (VLSI) Design Laboratory, Indian Institute of Tech-
`nology, Kharagpur, India. From 2003 to 2005, he was a Graduate Research
`Assistant with the Microwave Application Group, Georgia Electronic Design
`Center, Georgia Institute of Technology. From 2005 to 2006, he was an Intern
`with the Communication Circuits Laboratory, Intel Corporation, Hillsboro, OR.
`
`Jing-Hong C. Zhan (S’97–M’04) received the B.S.
`and M.S. degrees in electrical engineering from
`Tsing-Hua University, HsinChu, Taiwan, R.O.C., in
`1996 and 1997, respectively, and the Ph.D. degree
`in electrical engineering and computer science in
`Cornell University, Ithaca, NY, in 2004. His M.S.
`thesis concerned side-polished fiber fabrication and
`theoretical analysis. His doctoral research focused on
`voltage-controlled oscillator (VCO) and high-speed
`clock and data recovery circuitry using BiCMOS
`and CMOS.
`Upon completion of compulsory services with the Taiwanese Army, where
`he served as a Secondary Lieutenant from 1997 to 1999, he joined MediaTek,
`HsinChu, Taiwan, R.O.C., where he was a Logic Design Engineer until 2001.
`He developed the data path and spindle motor control circuitry for MediaTek’s
`optical storage products. In 2004, he joined the Communications Circuit Labora-
`tory, Intel Corporation, Hillsboro, OR, where he was a Senior Design Engineer.
`His research focused on fabricating low-cost radios on CMOS technologies for
`microprocessors production. In 2006, he joined the RF Division, MediaTek, as
`a Technical Manager, where he led a silicon tuner front-end design team. He
`codeveloped an all-digital phase-locked loop (PLL) for wireless applications.
`His recent research interest is millimeter-wave circuit design.
`
`Stewart S. Taylor
`(S’74–M’94–SM’99–F’08)
`received the Ph.D. degree in electrical engineering
`from the University of California at Berkeley, in
`1978.
`Since January 2003, he has been a Senior Principal
`Design Engineer with the Communications Circuits
`Laboratory, Intel Corporation, Hillsboro, OR. His
`current research is focused on radio architecture and
`circuit design that leverages the strengths and com-
`pensates for the weaknesses of CMOS technology.
`Prior to joining the Intel Corporation, he was with
`Tektronix, TriQuint, and Maxim. He has developed high-speed analog, data
`converter, and wireless/RF integrated circuits. He holds 41 patents with 23
`pending. For 29 years, he has taught on a part-time basis at Portland State
`University, Oregon State University, and the Oregon Graduate Institute.
`Dr. Taylor served on the Program Committee of the International Solid-State
`Circuits Conference for ten years and chaired the Analog Subcommittee for four
`years. He was the conference program chair in 1999. He was an associate ed-
`itor for the IEEE JOURNAL OF SOLID-STATE CIRCUITS. He was the recipient of
`the IEEE Third Millennium Medal for Outstanding Achievements and Contri-
`butions from the Solid-State Circuits Society.
`
`Brent R. Carlton (S’01–M’02) was born in Gillette,
`WY. He received the B.S. and M.S. degrees in elec-
`trical engineering from Brigham Young University,
`Provo, UT, in 2003.
`Since 2002, he has been a Wireless Circuits
`Researcher with the Corporate Technology Group,
`Intel Corporation, Hillsboro, OR. While with the
`Intel Corporation, he has been involved with wireless
`receiver design, testing, and architecture. Some of
`the circuits he has designed and tested include both
`wideband and narrowband LNA circuits, receive
`mixers, baseband amplifiers, and mixed-signal circuits.
`
`Joy Laskar (S’84–M’85–SM’02–F’05)
`received
`the B.S. degree in computer engineering (with
`math/physics minors) (summa cum laude) from
`Clemson University, Clemson, SC, in 1985, and the
`M.S. and Ph.D. degrees in electrical engineering
`from the University of Illinois at Urbana-Cham-
`paign, in 1989 and 1991, respectively.
`Prior to joining the Georgia Institute of Tech-
`nology, Atlanta, in 1995, he was a Visiting Professor
`with the University of Illinois at Urbana-Champaign,
`and an Assistant Professor with the University of
`Hawaii at Manoa. With the Georgia Institute of Technology, he holds the
`Schlumberger Chair in Microelectronics with the School of Electrical and
`Computer Engineering. He is also the Founder and Director of the Georgia
`Electronic Design Center, and hea

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