1. H. Aminzadeh, R. Lotfi, K. Mafinezhad, “Low-dropout voltage reference: an approach to low-temperature-sensitivity architectures with high drive capability,” in IET Electronics Letters, Vol. 45, No.24, pp.1200-1201, Nov. 2009.
2. H. Rezaee D., N. Ravanshad, R. Lotfi, K. Mafinezhad, “Modified Model for Settling Behavior of Operational Amplifiers in Nano-Scale CMOS,” in IEEE Transactions on Circuits and Systems-II, Vol. 56, No.5, pp.384-388, May 2009.
3. H. Aminzadeh, R. Lotfi, “Design of Low-Power Single-Stage Operational Amplifiers Based on an Optimized Settling Model,” in Analog Integrated Circuits and Signal Processing, Springer Publishers, Vol. 58, No. 2, pp.153-160, Feb. 2009.
4. H. Aminzadeh, R. Lotfi, K. Mafinezhad, “Low-cost area-efficient low-dropout regulators using MOSFET capacitors,” in IEICE Electronics Express, ELEX, Vol. 5, No.16, pp.610-616, August. 2008
5. S. A. Zabihian, R. Lotfi, “A sub-1V high-gain single-stage operational amplifier,” in IEICE Electronics Express, ELEX, Vol. 5, No.7, pp.211-216, Apr. 2008.
6. H. Aminzadeh, M. Danaie, R. Lotfi, “Design of high-speed two-stage cascode-compensated operational amplifiers based on settling time and open-loop parameters,” in Integration, the VLSI Journal, Vol. 41, Feb. 2008, pp. 183-192.
7. H. Aminzadeh, R. Lotfi, “On the Power Efficiency of Cascode Compensation over Miller Compensation in Two-Stage Operational Amplifiers,” Journal of Circuits, Systems and Computers, JCSC, Vol. 16, No. 6, Feb. 2008.
8. H. Aminzadeh R. Lotfi, "Design Guidelines for High-Speed Two-Stage CMOS Operational Amplifiers," Arabian Journal of Science and technology (AJSE), Vol. 32, No. 2C, Dec. 2007.
9. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, “Analysis of dynamic non-linearities in pipelined ADCs,” in IEICE Trans. Electronics, June 2004.
10. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, “A pseudo-class-AB telescopic-cascode operational Amplifier,” in IEE Electronics Letters, Feb. 2004.
11. R. Lotfi, M. Taherzadeh-Sani, M. Y. Azizi, and O. Shoaei, “Low-Power Design Techniques for Low-Voltage Fast-Settling Operational Amplifiers in Switched-Capacitor Applications,” in Integration, the VLSI Journal, Elsevier Publisher, vol.36/4, pp.175-189, 2003.
Conference Papers
1. M. Saberi, and R. Lotfi, “Analysis of the Linearity of Pipelined ADC Due to Capacitor Non-linearity," in Proc. IEEE Intl. Conf. on Electronics, Circuits, and Systems, ICECS 2009, pp. 403-406, 2009.
2. E. Rahiminejad, and R. Lotfi, “A Low-Power Architecture for Integrating Analog-to-Digital Converters," in Proc. IEEE Intl. Conf. on Electronics, Circuits, and Systems, ICECS 2009, pp. 411-414, 2009.
3. R.Lotfi, R. Majidi, M. Mymandi-Nejad, W.A. Serdijn, “An Ultra-Low-Power 10-Bit 100-kS/s Successive-Approximation Analog-to-Digital Converter,“ in Proc. of IEEE International Symposium on Circuits and Systems, pp.1117-1120, ISCAS 2009.
4. S. M. Hokmabadi, R. Lotfi, M. Saberi, “A 1-V 10-bit 80MS/s Current-Steering DAC Using Body-Driven Enhanced-Impedance Current Source,” in Proc. of Iranian Conf. on Electrical Engineering, (in Persian) May, 2008.
5. S. M. Hokmabadi, R. Lotfi, “Modified Decoding Structure in Current-Steering DACs to Improve Linearity,” in Proc. of Iranian Conf. on Electrical Engineering, (in Persian) May, 2008.
6. S. M. Hokmabadi, S. A. Zabihian and R. Lotfi, “Body-Driven Enhanced-Impedance Current Source: An Approach to the Implementation of Low-Voltage Current-Steering D/A Converters,” in Proc. of IEEE Intl. Conf. on Electronics, Circuits, and Systems, ICECS 2007.
7. M. Saberi, and R. Lotfi, “A Capacitor Mismatch- and Nonlinearity-Insensitive 1.5-Bit Residue Stage for Pipelined ADCs ,” in Proc. of IEEE Intl. Conf. on Electronics, Circuits, and Systems, ICECS 2007.
8. H. Aminzadeh, M. Danaie, and R. Lotfi, “Design of High-Resolution MOSFET-Only Pipelined ADCs with Digital Calibration,” in Proc. of DATE (Design Automation and Test in Europe) Conference, 2007.
9. S.A. Zabihian, R.Lotfi, “Ultra-Low-Voltage, Low-Power, High-Speed Operational Amplifiers Using Body-Driven Gain-Boosting Technique “ in Proc. International Symposium on Circuits and Systems (ISCAS), 2007.
10. H. Sarbishaei, T. Kahookar T., E. Zhian T., and R. Lotfi, "Power optimization in low-voltage high-speed high-resolution pipelined ADCs," in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), 2006.
11. H. Shamsi, S. Radiom, R. Lotfi, and O. Shoaei, "A straightforward design methodology for multi-bit continuous time delta-sigma modulators," in Proc. IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), 2006.
12. M. Nabavi, and R. Lotfi, "A 1-V 12-bit switched-opamp pipeline ADC with power optimization," in Proc. of International Symposium on Circuits and Systems (ISCAS), Greece, 2006.
13. H. Charkhkar, A. Asadi, and R. Lotfi, "A 1.8-V 10-bit 40MS/s MOSFET-only pipeline analog-to-digital converter," in Proc. of International Symposium on Circuits and Systems (ISCAS), Greece, 2006.
14. T. Kahookar T., E. Zhian T., H. Sarbishaei, and R. Lotfi, "ISECAD: An iterative equation-simulation-based opamp-design CAD tool," in Proc. of International Symposium on Circuits and Systems (ISCAS), Greece, 2006.
15. S. Radiom, B. Sheikholeslami, H. Aminzadeh, and R. Lotfi, "Folded current-steering DAC: An approach to low-voltage high-speed high-resolution D/A converters," in Proc. International Symposium on Circuits and Systems (ISCAS), Greece, 2006.
16. H. Adrang, R. Lotfi, A. Tajalli, and S. Mehrmanesh, "A low-power CMOS Gm-C filter for wireless applications with on-chip automatic tuning," in Proc. International Symposium on Circuits and Systems (ISCAS), Greece, 2006.
17. H. Aminzadeh, and R. Lotfi, "New analysis for cascode compensation in two-stage operational amplifiers," in Proc. Northeast Workshop on Circuits and Systems, NEWCAS’06.
18. M. Nabavi, and R. Lotfi, "Switched-Capacitor Reference Voltage Generator for Deep Low-Voltage High-Resolution Pipelined ADCs" in 5th International Conference for Upcoming Engineer, ICUE 2006.
19. M. Nabavi, and R. Lotfi, "Switched-opamp technique for 1-V 12-bit ADC," in Proc. Midwest Symposium on Circuits and Systems (MWSCAS), Cincinnati, 2005, pp.851-854.
20. H. Sarbishei, T. K. Toosi, E. Zhian, and R. Lotfi, "A high-speed high-gain low-power class-AB operational amplifier," in Proc. Midwest Symposium on Circuits and Systems (MWSCAS), Cincinnati, 2005, pp.271-274.
21. M. Danaie, and R. Lotfi, "A low-voltage high-PSRR CMOS PTAT and constant-gm reference circuit," in Proc. Midwest Symposium on Circuits and Systems (MWSCAS), Cincinnati, 2005, pp.1807-10.
22. M. Nabavi, and R. Lotfi, "Design of an ultra-low-voltage switched-opamp pipelined ADC," (in Persian) in Proc. of Iranian Conf. on Electrical Engineering, ICEE, 2007.
23. M. Saberi, M. Hokmabadi, and R. Lotfi, "A 10-bit 20MS/s 1-V pipelined ADC using the switched-opamp technique and gate-bulk capacitances of MOSFETs,” (in Persian) in Proc. of Iranian Conf. on Electrical Engineering, ICEE, 2007.
24. M. H. Maghami, R. Lotfi, "Automatic design of operational amplifiers using geometric programming,” (in Persian) in Proc. of Iranian Conf. on Electrical Engineering, ICEE, 2007.
25. H. Aminzadeh, R. Lotfi, "Design of MOSFET-only pipelined ADCs using digital calibration,” (in Persian) in Proc. of Iranian Conf. on Electrical Engineering, ICEE, 2007.
26. S. A. Zabihian, R. Lotfi, "Low-Voltage very- High-Gain High-Speed Operational Amplifier Using Body-Driven Gain-Boosting Technique,” in Proc. of Iranian Conf. on Electrical Engineering, ICEE, 2007.
27. R. Ghasemi, H. Charkhkar, A. Asadi, R. Lotfi, k. Mafinezhad "Design of low-voltage MOSFET-only switched-capacitor filters," in Proc. International Conference on Microelectronics, ICM 2005.
28. R. Lotfi, M. Taherzadeh-Sani, and O. Shoaei, "Power consumption issues in high-speed high-resolution pipelined analog-to-digital converters," in proceedings of International Symposium on Circuits and Systems (ISCAS), Kobe, Japan, pp. 4618-4621, 2005.
29. R. Lotfi, M. Taherzadeh-Sani, M. Y. Azizi, and O. Shoaei, "Systematic Design for Power Minimization of Pipelined Analog-to-Digital Converters," in proceedings of International Conference on Computer Aided Design (ICCAD), San Jose, CA, USA, pp. 371-374, 2003.
30. R. Lotfi, M. Taherzadeh-Sani, O. Shoaei, “A 12-bit 40MSPS 3.3-V 56-mW Pipelined A/D Converter in 0.25-um CMOS,” in Proc. of IEEE International Symposium on Circuits and Systems, ISCAS 2004, vol.1, pp.I-69- I-72.
31. R. Lotfi, M. Taherzadeh-Sani, M. Y. Azizi, and O. Shoaei, "Systematic Design for Optimization of High-Resolution Pipelined Analog-to-Digital Converters," in proceedings of International Symposium on Low Power Electronic Design (ISLPED), South Korea, pp. 334-339, 2003.
32. R. Lotfi, M. Taherzadeh-Sani and O. Shoaei, "A 1.5-V 12-bit 75M-Samples/s Fully-Differential Low-Power Sample-and-Hold Amplifier in 0.25-um CMOS," in proceedings of International Conference on Electronics, Circuit and Systems, (ICECS), pp. 814-817, 2003.
33. R. Lotfi, M. Taherzadeh-Sani, M. Y. Azizi, and O. Shoaei, "A 1-V MOSFET-Only Fully-Differential Dynamic Comparator For Use in Low-Voltage Pipelined A/D Converters," in proceedings of Signal Circuit and Systems Conference (SCS), Romania, pp. 377-380, 2003.
34. R. Lotfi, O. Shoaei, “A Low-Voltage Low-Power Fast-Settling Operational Amplifier for Use in High-Speed High-Resolution Pipelined A/D Converters,” in Proc. of IEEE International Symposium on Circuits and Systems, ISCAS 2002, vol.2, pp.416-419.
35. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, "Systematic Design for Optimization of High-Resolution Pipelined ADCs," in proc. Design Automation and Test in Europe, ip1_08, (DATE), 2004.
36. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, "A Statistical Approach to Estimate the Dynamic Non-linearity Parameters of Pipeline ADCs," in proceedings of International Conference on Computer Aided Design (ICCAD), San Jose, CA, USA, pp. 367-370, 2003.
37. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, "An Analytical Approach to the Estimation of Dynamic Non-linearity Parameters in Pipeline A/D Converters," in proceedings of European Solid State Circuits Conference, (ESSCIRC), Portugal, pp. 715-718, 2003.
38. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, "A Novel Frequency Compensation Technique for Two-Stage CMOS Operational Amplifiers," in proceedings of International Conference on Electronics, Circuit and Systems, (ICECS), pp. 256-259, 2003.
39. M. Taherzadeh-Sani, R. Lotfi, and O. Shoaei, "An Analytical Approach to the Estimation of Spurious Free Dynamic Range in Pipeline A/D Converters," in proceedings of International Conference on Electronics, Circuit and Systems, (ICECS), pp. 946-949, 2003.
40. M. Taherzadeh-Sani, R. Lotfi, H. Z. Hoseini, and O. Shoaei, "Design Optimization of Analog Integrated Circuits Using Simulation-Based Genetic Algorithm," in proceedings of Signal Circuit and Systems Conference(SCS), Romania, pp. 73-76, 2003.
41. M. Taherzadeh-Sani, R. Lotfi, H. Z. Hoseini, and O. Shoaei, "A High Slew-Rate Low-Voltage Low-Power Operational Amplifier Using a New Current Injection Circuit," in proceedings of Signal Circuit and Systems Conference(SCS), Romania, pp. 481-484, 2003.
42. A. Ahmadi, R.Lotfi, M. Sharif-Bakhtiar, “A novel rail-to-rail input constant-gm operational amplifier, “ Proc. of IEEE Intl. Symp. on Low-Power Electronics and Design, ISLPED 2003.
43. Z. Olia, R.Lotfi, and S. H. Keshmiri, “A 1-V 10-bit 10MS/s switched-opamp A/D converter,” in Proc. of 12th Iranian Conference on Electrical Engineering, ICEE 2004.
44. H. Aslanzadeh, S. Mehrmanesh, V. Vahidfar, S. Safarian, R. Lotfi, “ A 1-V 1-mW high-speed class-AB operational amplifier for high-speed low-power pipelined A/D converters using Slew Boost Technique“ accepted to be published in Proc. of IEEE Intl. Symp. on Low-Power Electronics and Design, ISLPED 2003.
45. H. Ghandeharion, M. Tabandeh, R. Lotfi, ”A 0.8-V 900-MHz CMOS low-noise amplifier” in Proc. of 11th Iranian Conf. On Electrical Engineering, ICEE 2003.
46. T. Kahookar T., E. Zhian T., H. Sarbishaei, and R. Lotfi, "Automatic CAD-tool for high-performance operational amplifiers based on equation and simulation," accepted to be presented in 14th Iranian Conference on Electrical Engineering, ICEE 2006.
47. M. Danaie, H. Rezaee, and R. Lotfi, "A CAD tool for design of linear MOSCAP structures using modified version of genetic programming," accepted to be presented in 14th Iranian Conference on Electrical Engineering, ICEE 2006.
48. R. Lotfi, S.M. Atarodi, ”A new transistor configuration for use in a low-voltage low-power operational amplifier,” in 8th Iranian Conference on Electrical Engineering, ICEE 2000, pp. 81-86.
49. R. Lotfi, S.M. Atarodi, ”A low-voltage low-power switched-capacitor filter using a new transistor configuration,” in Proc. of IEEE International Conference on Microelectronics, ICM 2000, pp.99-102.
50. M. Esmaeili, M. F.Baroughi, R. Lotfi, ” Micro-machining, A Tutorial,” in the first Iranian Student Conference on Electrical Engineering, ISCEE 1998.
51. R. Lotfi, PhD Research abstract: “A low-power design methodology for operational amplifiers in pipelined A/D converters,” accepted to be presented in 1st EDAA PhD forum at DATE 2003.
52. R. Lotfi, PhD Research abstract: “Systematic design for power minimization of pipelined A/D converters,” presented in 2nd EDAA PhD forum at DATE 2004.