Low-Power RF Integrated Circuit Design Techniques for Short-Range - PowerPoint PPT Presentation

Low-Power RF Integrated Circuit Design Techniques for Short-Range Wireless Connectivity Marvin Onabajo Assistant Professor Analog and Mixed-Signal Integrated Circuits (AMSIC) Research Laboratory Dept. of Electrical and Computer Engineering Northeastern University, Boston, USA Email: monabajo@ece.neu.edu Website: www.ece.neu.edu/~monabajo ES2 Northeastern University Planning Grant Meeting November 30, 2017

AMSIC Research Lab Outline • Introduction – Motivation for low-power RF CMOS circuit design – Technical challenges • Linearity improvement method for subthreshold low-noise amplifiers – Theory and simulation – Measurement results • Integrated RF front-end chip – Low-noise amplifier and mixer – Measurement results • Conclusions 2

AMSIC Research Lab Health Monitoring Application Example: Wireless Body Area Network (WBAN)  Circuit design challenges (in addition to performance, size, reliability, cost) Reduction of power consumption to extend battery lifetime  Resilience to interference signals  3

AMSIC Research Lab Subthreshold RF Design Considerations • Power efficiency → Higher transconductance-to-drain current (g m /I D ) ratio than in the strong inversion region → Suitable for low supply voltages • Lower transition frequency ( ω T ≈ g m /C gg ) • Capacitance C gs does not dominate in the subthreshold region → Other parasitic capacitances (C gd and C gb ) should be carefully taken into account 4

AMSIC Research Lab Subthreshold RF Design Considerations (cont.) For a weakly nonlinear transconductance amplification stage:       2 3 i g v g v g v d 1 gs 2 gs 3 gs where: g 1 = g m (linear transconductance gain) g 2 and g 3 are the 2 nd -order and 3 rd -order nonlinearity coefficients    2 3 I 1 I 1 I      D D D g , g , g    1 2 3 2 3 V 2 V 6 V GS GS GS • Subthreshold linearity characteristics → Sign change of g 3 /g 1 → High g 3 /g 1 ratio (signal distortion) 5

AMSIC Research Lab Linearized Subthreshold Low-Noise Amplifier (LNA) Z 3 • 3 rd -order nonlinearity (distortion) cancellation – Without active components → minimization of power consumption – No cross-coupling is required → permits the use of a single -ended architecture C.-H. Chang and M. Onabajo, “Linearization of subthreshold low-noise amplifiers,” in Proc. IEEE Intl. Symp. on Circuits and Systems (ISCAS) , pp. 377-380, May 2013. 6

AMSIC Research Lab 3rd-Order Intermodulation Intercept Point (IIP3) Analysis result: 1  IIP 3     3      6 R H ( ) A ( ) ( , 2 ) s 1      g  Z 3 ( , 2 ) g where: 3 oB   2 2 1   2   g oB g      2   3 g g ( ) g g ( 2 ) 1 1               1 j C Z ( ) Z ( ) j C Z ( ) Z ( )   gd 1 1 3 gs 1 1 x g ( )  Z ( ) x                 ]                  Z Z j C [ Z Z Z Z Z Z x 2 gd 1 1 2 1 3 2 3 7

AMSIC Research Lab IIP3 Evaluation with Various L g2 and C gd2_ext Values 8

AMSIC Research Lab Chip Micrographs of Fabricated Linearized Subthreshold LNAs (a) “Work 1” (b) “Work 2” (a) Dongbu 0.11 μm CMOS technology C.- H. Chang and M. Onabajo, “Low -power low-noise amplifier IIP3 improvement under consideration of the cascode stage,” in Proc. IEEE Intl. Symp. on Circuits and Systems (ISCAS) , May 2017. (b) IBM 0.13 μm CMOS technology 9

AMSIC Research Lab LNA Printed Circuit Board with IIP3 Tuning Functionality 10

AMSIC Research Lab Comparison with Other Subthreshold LNAs [5] § Work 1 + Work 2 + [1] + [2] + [3] # [4] $ Reference f c [GHz] 1.8 2.1 2.4 3 1 2.4 1 S 21 [dB] 14.8 9 21.4 4.5 13.6 13.1 16.8 NF [dB] 3.7 5.8 5.2 6.3 4.6 5.3 3.9 IIP3 [dBm] -11 -10.5 7.2 -12.2 -11.2 -3.7 0 P 1dB [dBm] -12.6 -8.4 -15 -19.5 0.2 -19 -21 P DC [μW] 336 300 1134 156 260 60 100 Tech. [ μm ] 0.11 0.13 0.18 0.13 0.18 0.13 0.18 Layout [mm 2 ] 0.624 0.24 0.717 2.0 0.694 0.63 0.809 (# of Ind.) (1) (4) (3) (2) (1) (3) (3) FOM 9.7 8.5 -0.7 -0.5 17.1 -6.6 5.6 + measured in package (cascode topology) # probe measurements (single-transistor topology) $ measured in package (self-biased inverter topology) § measured in package (inductive feedback topology)     Gain [ abs ] IIP 3 [ mW ] f [ GHz ]     FOM 10 log       ( NF [ abs ] 1 ) PD [ mW ] 11

AMSIC Research Lab References [1] A. V. Do, C. C. Boon, M. A. Do, K. S. Yeo, and A. Cabuk, “A subthreshold low-noise amplifier optimized for ultra-low-power applications in the ISM band,” IEEE Transactions on Microwave Theory and Techniques , vol. 56, no. 2, pp. 286-292, Feb. 2008. [2] H. Lee and S. Mohammadi, “A 3GHz subthreshold CMOS low noise amplifier,” in Proc. Radio Frequency Integrated Circuits (RFIC) Symp. , June 2006. [3] B. G. Perumana, S. Chakraborty, C.-H. Lee, J. and Laskar, “A fully monolithic 260- μW, 1-GHz subthreshold low noise amplifier,” IEEE Microwave Theory and Wireless Component Letters , vol. 15, no. 6, pp. 428 - 430 , June 2005. [4] T. Taris, J. Begueret, and Y. Deval, “A 60 μW LNA for 2.4 GHz wireless sensors network applications,” in Proc. Radio Frequency Integrated Circuits (RFIC) Symp. , June 2011. [5] A. Shameli and P. Heydari, “A novel ultra low power low noise amplifier using differential inductor feedback,” IEEE European Solid State Circuit Conference (ESSCIRC) , Sep. 2006, pp. 352-355. 12

AMSIC Research Lab Low-Power RF Front-End  Combined LNA & mixer to demonstrate the compatibility of the linearization techniques  Proof-of-concept measurements L. Xu, C.-H. Chang, and M. Onabajo, “A 0.77mW 2.4GHz RF front-end with -4.5dBm in-band IIP3 through inherent filtering,” IEEE Microwave and Wireless Components Letters (MWCL) , vol. 26, no. 5, pp. 352-354, May 2016. 13

AMSIC Research Lab Die Micrograph of the RF Front-End (0.13 μ m CMOS Technology) 14

AMSIC Research Lab Measurement Setup Measured voltages at the intermediate frequency (IF) outputs Simulated voltages at the IF outputs 15

AMSIC Research Lab Performance Summary and Comparison 16

AMSIC Research Lab References [6] A. Selvakumar, M. Zargham, and A. Liscidini, “Sub -mW Current Re-Use Receiver Front- End for Wireless Sensor Network Applications,” IEEE J. Solid-State Circuits , vol. 50, no. 12, Dec. 2015. [7] Z. Lin, P.-I. Mak, and R. P. Martins, “A 0.14-mm 2 1.4-mW 59.4-dB-SFDR 2.4 GHz ZigBee/WPAN Receiver Exploiting a Split-LNTA + 50% LO topology in 65-nm CMOS ,” IEEE Trans. on Microwave Theory and Techniques , vol. 62, no. 7, pp. 1525-1534, Jul. 2014. [8] Z. Lin, P.-I. Mak and R. P. Martins, “A 2.4-GHz ZigBee Receiver Exploiting an RF-to-BB- Current-Reuse Blixer + Hybrid Filter Topology in 65-nm CMOS ,” IEEE J. of Solid-State Circuits , vol. 49, pp. 1333-1344, June 2014. [9] F. Zhang, K. Wang, J. Koo, Y. Miyahara, and B. Otis, “A 1.6mW 300mV-Supply 2.4GHz Receiver with -94dBm Sensitivity for Energy-Harvesting Applications,” in Int. Solid-State Circuits Conf. Tech. Dig. , pp. 456-457, Feb. 2013. [10] B. W. Cook, A. D. Berny, A. Molnar, S. Lanzisera, and K. S. J. Pister, “Low -power 2.4- GHz Transceiver With Passive RX Front-End and 400-mV Supply,” IEEE J. Solid-State Circuits , vol. 41, no. 12, pp. 2757-2766, Dec. 2006. 17

AMSIC Research Lab Conclusion • Subthreshold LNA linearization method to enable low-power design – Extra inductor and capacitor for nonlinearity cancellation – Negligible impact on power, noise and gain design tradeoffs – IIP3 improvement: 4.8-11.2 dB – 1-dB compression point improvement: 7.1-11.6 dB • Linearization techniques for low-power RF front-ends in short-range wireless communication devices – Adaptation of the linearization technique for low-power active mixers – Demonstrated with a low-power linearized RF front-end • The design methods do not require an auxiliary amplifier circuit → Suitable for low -power applications 18

AMSIC Research Lab Thank You. Questions are Welcome. Marvin Onabajo Analog and Mixed-Signal Integrated Circuits (AMSIC) Research Laboratory Dept. of Electrical and Computer Engineering Northeastern University, Boston, USA Email: monabajo@ece.neu.edu Website: www.ece.neu.edu/~monabajo The projects were supported in part by the National Science Foundation under awards #1349692 and #1451213.

AMSIC Research Lab Appendix ↓

AMSIC Research Lab Examples of Low-Power Wireless Communication Standards Wireless Personal Area Network Wireless Body Area Network (WPAN) (WBAN) Bluetooth Low IEEE 802.15.4 IEEE 802.15.6 Energy (BLE) (ZigBee) 2.4 GHz, 2.4-2.2483 GHz, Frequency 2.4-2.4835 GHz 868 MHz, 2.36-2.4 GHz(US), Range 915 MHz, (400/868/915/950 MHz) Data Rate 1 Mbps 20 Kbps – 250 Kbps 75.9 Kbps – 971.4 Kbps Network Size undefined up to 65536 devices up to 256 devices Range 10-75 m 10-100 m 2-5 m 21