The architecture, design and implementation of a low power complementary metal-oxide semiconductor (CMOS) class-G audio amplifier with gradual power-supply switching (GPSS) are presented. The proposed class-G amplifier output stage strategically uses the parallel connection of a class-AB output stage operating from smaller supplies (V _DDL/V _SSL), and a class-C output stage (with crossover from V _SSL to V _DDL) operating from higher supplies (V _DDH/V _SSH). GPSS is achieved using an efficient biasing scheme with level shifters. Moreover, the proposed biasing scheme in conjunction with negative feedback enables low distortion during the power-supply transition. Experimentally, the class-G amplifier prototype achieves a −82.5 dB THD + N, a peak load power of 50 mW and a quiescent power consumption of 350 μW. The proposed class-G amplifier was implemented in a standard CMOS 90 nm technology and occupies an active silicon area of 0.08 mm².

References

1. 1)
  - 17. Pierdomenico, J., Wurcer, S., Day, B.: ‘A 684-mW adaptive supply full-rate ADSL CO driver’, IEEE J. Solid-State Circuits, 2002, 37, (12), pp. 1831–1838 (doi: 10.1109/JSSC.2002.804343).
2. 2)
  - 1. John, G.: ‘AN-1737 Managing EMI in Class D Audio Applications’ (Texas Intruments Inc., Dallas, TX, May 2013), Accessed on March 2014. Available at http://www.ti.com/lit/an/snaa050a/snaa050a.pdf.
3. 3)
  - 23. Monticelli, D.: ‘A Quad CMOS Single-supply Op Amp with Rail-to-Rail Output Swing’, IEEE J. Solid-State Circuits, 1986, 21, (6), pp. 1026–1034 (doi: 10.1109/JSSC.1986.1052645).
4. 4)
  - 28. Grasso, A., Palumbo, G., Pennisi, S.: ‘Advances in reversed nested miller compensation’, IEEE Trans. Circuits Syst. I, 2007, 54, (7), pp. 1459–1470 (doi: 10.1109/TCSI.2007.900170).
5. 5)
  - 11. Self, D.: ‘Audio power amplifier design handbook’ (Focal Pr, Oxford, UK, 2009).
6. 6)
  - 7. Raab, F.: ‘Average efficiency of class-G power amplifiers’, IEEE Trans. Consum. Electron., 1986, CE-32, (2), pp. 145–150 (doi: 10.1109/TCE.1986.290146).
7. 7)
  - 3. Samsung Galaxy SIII GT-I9300 User manual. Samsung Electronics Inc., UK., Accessed on March 2014. Available at http://www.samsung.com/uk/support/model/GT-I9300MBDBTU-downloads?isManualDownload=true.
8. 8)
  - 26. Fan, X., Mishra, C., Sanchez-Sinencio, E.: ‘Single miller capacitor frequency compensation technique for low-power multistage amplifiers’, IEEE J. Solid-State Circuits, 2005, 40, (3), pp. 584–592 (doi: 10.1109/JSSC.2005.843602).
9. 9)
  - 8. Lollio, A., Bollati, G., Castello, R.: ‘A class-G headphone amplifier in 65 nm CMOS technology’, IEEE J. Solid-State Circuits, 2010, 45, (12), pp. 2530–2542 (doi: 10.1109/JSSC.2010.2076450).
10. 10)
  - 10. Galal, S., Zheng, H., Abdelfattah, K., et al: ‘A 60 mW class-G stereo headphone driver for portable battery-powered devices’, IEEE J. Solid-State Circuits, 2012, 47, (8), pp. 1921–1934 (doi: 10.1109/JSSC.2012.2197155).
11. 11)
  - 20. Shorb, J., Allstot, D., Roze, R.: ‘Class AB-D-G line driver for central office asymmetric digital subscriber line systems’. IEEE Proc. Int. Symp. on Circuits and Systems (ISCAS), May 2002, vol. 5, pp. 405–408.
12. 12)
  - 18. Quarfoot, J., Corsi, M., Hester, R., Maclean, K.: ‘Zero-overhead class G Amplifier with Threshold Detection’. US Patent Application no. 10/001,330, October 2001.
13. 13)
  - 9. Chen, J., Arunachalam, S., Brooks, T., Mehr, I., Cheung, F., Venkatram, H.: ‘A 62 mW stereo class-G headphone driver with 108 dB dynamic range and 600 μA channel quiescent current’. IEEE Int. Solid-State Circuits Conf. (ISSCC) Digest of Technical Papers, February 2013, pp. 182–183.
14. 14)
  - 19. Somerville, T., Wortel, K.: ‘Efficient class-G amplifier with wide output voltage swing’. US Patent App lication no. 10/622,051, July 2003.
15. 15)
  - 16. Class G headphone amplifier with I2C volume control. Texas Intruments Inc., Dallas, TX., August 2009, Accessed on March 2014. Available at http://www.ti.com.cn/cn/lit/ds/symlink/lm48824.pdf.
16. 16)
  - 24. Eschauzier, R.G.H., Kerklaan, L., Huijsing, J.H.: ‘A 100-MHz 100-dB operational amplifier with multipath nested miller compensation structure’, IEEE J. Solid-State Circuits, 1992, 27, (12), pp. 1709–1717 (doi: 10.1109/4.173096).
17. 17)
  - 4. Dhanasekaran, V., Silva-Martinez, J., Sanchez-Sinencio, E.: ‘Design of three-stage class-AB 16 headphone driver capable of handling wide range of load capacitance’, IEEE J. Solid-State Circuits, 2009, 44, (6), pp. 1734–1744 (doi: 10.1109/JSSC.2009.2020461).
18. 18)
  - 2. Colli-Menchi, A., Torres, J., Sanchez-Sinencio, E.: ‘A feed-forward power-supply noise cancellation technique for single-ended class-D audio amplifiers’, IEEE J. Solid-State Circuits, 2014, 49, (3), pp. 718–728 (doi: 10.1109/JSSC.2014.2298456).
19. 19)
  - 15. Class-G directpath stereo headphone amplifier with I2C volume control. Texas Intruments Inc., Dallas, TX., Mar. 2009, Accessed on March 2014. Available at http://www.ti.com/lit/ds/slos598a/slos598a.pdf.
20. 20)
  - 27. Leung, K.N., Mok, P.: ‘Analysis of multistage amplifier-frequency compensation’, IEEE Trans. Circuits Syst. I, 2001, 48, (9), pp. 1041–1056 (doi: 10.1109/81.948432).
21. 21)
  - 14. Feldman, L.: ‘Class-G high efficiency hi-fi amplifier’, Radio Electron., 1976, 47, (8), p. 47.
22. 22)
  - 5. Mohan, C., Furth, P.: ‘A 16-Ωaudio amplifier with 93.8-mW peak load power and 1.43-mW quiescent power consumption’, IEEE Trans. Circuits Syst. II: Express Briefs, 2012, 59, (3), pp. 133–137 (doi: 10.1109/TCSII.2012.2186361).
23. 23)
  - 6. Abdelfattah, K., Galal, S., Mehr, I., et al: ‘A direct-battery hookup, fully integrated stereo headphone module with 82 mW output power and 110 dB PSRR’. IEEE Custom Integrated Circuits Conf. (CICC), September 2013, pp. 1–4.
24. 24)
  - 22. 2.4 W, single-supply class G power amplifier. Maxim Semiconductors Inc., Dallas, TX., Rev. 5, March 2010, Accessed on March 2014. Available at http://datasheets.maximintegrated.com/en/ds/MAX9730.pdf.
25. 25)
  - 13. Sampei, T., Ohashi, S., Ohta, Y., Inoue, S.: ‘Highest efficiency and super quality audio amplifier using MOS power FETS in class G operation’, IEEE Trans. Consum. Electron., 1978, CE-24, (3), pp. 300–307 (doi: 10.1109/TCE.1978.267034).
26. 26)
  - 25. Eschauzier, R.G.H., Huijsing, J.H.: ‘Frequency compensation techniques for low-power operational amplifiers’ (Kluwer Academic Publishers, Dordrecht, The Netherlands, 1995).
27. 27)
  - 12. Downey, A., Wierzba, G.: ‘A class-G/FB audio amplifier’, IEEE Trans. Consum. Electron., 2007, 53, (4), pp. 1537–1545 (doi: 10.1109/TCE.2007.4429249).
28. 28)
  - 21. Bicakci, A., Kim, C.-S., Lee, S.-S.: ‘A CMOS line driver for ADSL central office applications’, IEEE J. Solid-State Circuits, 2003, 38, (12), pp. 2201–2208 (doi: 10.1109/JSSC.2003.818570).

Low power complementary metal-oxide semiconductor class-G audio amplifier with gradual power supply switching

References

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