Power management IC is an essential part of an integrated system which can find application in various areas such as mobile phones, PCs, servers, wearable devices, IoT sensors, solar, automotive and lighting. These applications require multiple lower and/or higher supply voltages generated from a single source. For instance, a smartphone requires supply voltage as low as 0.8V and as high as 30V generated from a single Li-ion battery. This power supply demand is catered by voltage regulators which could be linear low-drop out (LDO) regulator or switching dc-dc converter. These power regulators could be integrated within the SoC or be part of a separate power management chip depending upon the specifications. Below are the various research topics in power management we are working on:

• Analog and digital controllers for switching DC-DC converters
• Time based controllers for switching DC-DC converters
• Fast transient switching converters
• Low noise switching converters for RF applications
• DC-DC converters with auto tuning
• Techniques for efficiency improvement
• Fast transient and high PSRR LDO
• Digitally controlled LDO
• Energy Harvesting for IoT
• Highly efficient battery charger circuit
• Charge-pump circuits
• Power management for LCD and AMOLED displays
• LED drivers for camera flash, display backlight and LED lights

Below are some of our published research work in the area of power management IC:

• A. Santra and Q. A. Khan, “A High Gain, Low Offset Time-Based Operational Amplifier for Capacitive Loads with 36MHz UGB and 70µA Quiescent Current,” 2021 IEEE International Midwest Symposium on Circuits and Systems (MWSCAS), 2021, pp. 432-436, doi: 10.1109/MWSCAS47672.2021.9531892.
• S. Guddanti and Q. A. Khan, “A High Efficiency Fast Transient Zero Output Ripple Buck Converter Using Split PWM Controller with Inductor Mismatch Compensation,” 2021 IEEE International Symposium on Circuits and Systems (ISCAS), 2021.
• A. Chitnis, R. Chauhan, D. Kaur and Q. Khan, “A 0.75-5V, 15.8 nA with 1.8 μs Delay Supply Voltage Supervisor using Adaptively Biased Comparator and Sample & Hold Technique for IoT,” 2021 IEEE Custom Integrated Circuits Conference (CICC), 2021.
• A. D. Carmine, A. Santra, Q. Khan, “A current Efficient 10mA Analog-Assisted Digital Low Dropout Regulator with Dynamic Clock Frequency in 65nm CMOS,” 2020 International Symposium on Circuits and Systems (ISCAS), 17-20 May 2020, Seville, Spain.
• K. Peetala, A. Ranjan, R. Aenkamreddi, Q. Khan, “An Area Efficient, High-Resolution Fully Foldable Switched-Capacitor DC-DC Converter with 16% Efficiency Improvement,” 2020 International Symposium on Circuits and Systems (ISCAS), 17-20 May 2020, Seville, Spain.
• Abirmoya Santra, Angelo De Carmine, Guttha Venkata Sesha Rao, Qadeer A. Khan, “A Highly Scalable, Time-Based Capless Low-Dropout Regulator Using Master-Slave Domino Control,” 2019 IEEE International Symposium on Circuits and Systems (ISCAS), Sapporo, Japan, 2019, pp. 1-4.
• Abirmoya Santra and Qadeer A. Khan, “A Power Efficient Output Capacitor-Less LDO Regulator with Auto-Low Power Mode and Using Feed-forward Compensation,” 2019 32nd International Conference on VLSI Design and 2019 18th International Conference on Embedded Systems (VLSID), Delhi, NCR, India, 2019.
• B. Xiao et al., “An 80mA Capacitor-Less LDO with 6.5µA Quiescent Current and No Frequency Compensation Using Adaptive-Deadzone Ring Amplifier,” 2019 IEEE Asian Solid-State Circuits Conference (A-SSCC), 2019, pp. 39-42.
• Q. A. Khan, S. Saxena and A. Santra, “Area and Current Efficient Capacitor-Less Low Drop-Out Regulator Using Time-Based Error Amplifier,” 2018 IEEE International Symposium on Circuits and Systems (ISCAS), Florence, 2018, pp. 1-5.
• S. J. Kim, R. K. Nandwana, Q. Khan, R. Pilawa-Podgurski, and P. K. Hanumolu, “A 4-phase 30-70 MHz switching frequency buck converter using a time-based compensator,” IEEE Journal of Solid-State Circuits, vol. 50, no. 12, pp. 2814-2824, Dec. 2015.
• S. J. Kim, Q. Khan, M. Talegaonkar, A. Elshazly, A. Rao, N. Griesert, G. Winter, W. McIntyre and P. K. Hanumolu, “High Frequency Buck Converter Design Using Time-Based Control Techniques,“ IEEE Journal of Solid-State Circuits, vol. 50, no. 4, pp. 990-1001, April 2015.
• S. J. Kim; R. K. Nandwana, Q. Khan, R. Pilawa-Podgurski and P. K. Hanumolu, “12.2 A1.8V 30-to-70MHz 87% peak-efficiency 0.32mm2 4-phase time-based buck converter consuming 3μA/MHz quiescent current in 65nm CMOS,” 2015 IEEE International Solid-State Circuits Conference - (ISSCC) Digest of Technical Papers, San Francisco, CA, 2015, pp. 1-3.
• Q. Khan, S. J. Kim; M. Talegaonkar, A. Elshazly, A. Rao, N. Griesert, G. Winter, W. McIntyre and P. K. Hanumolu, “A 10–25MHz, 600mA buck converter using time-based PID compensator with 2µA/MHz quiescent current, 94% peak efficiency, and 1MHz BW,“ 2014 Symposium on VLSI Circuits Digest of Technical Papers, Honolulu, HI, 2014, pp. 1-2.
• Q. Khan, A. Elshazly, S. Rao,R. Inti and P. K. Hanumolu, “A 900mA 93% efficient 50µA quiescent current fixed frequency hysteretic buck converter using a highly digital hybrid voltage- and current-mode control,” 2012 Symposium on VLSI Circuits (VLSIC), Honolulu, HI, 2012, pp. 182-183.
• S. Rao. Q. Khan, S. Bang, D. Swank, A. Rao, W. McIntyre and P.K. Hanumolu, “A 1.2-A Buck-Boost LED Driver With On-Chip Error Averaged SenseFET-Based Current Sensing Technique,” IEEE Journal of Solid-State Circuits, Volume: 46, Issue: 12, pp 2772- 2783, Dec. 2011.
• Q. Khan, S. Rao, D. Swank, A. Rao, W. McIntyre, S. Bang and P.K. Hanumolu, “A 3.3V 500mA digital Buck-Boost converter with 92% peak efficiency using constant ON/OFF time delta-sigma fractional-N control,” 2011 Proceedings of the ESSCIRC (ESSCIRC), Helsinki, 2011, pp. 439-442.
• S. Rao. Q. Khan, S. Bang, D. Swank, A. Rao, W. McIntyre and P.K. Hanumolu, “A 1.2A buck-boost LED driver with 13% efficiency improvement using error-averaged SenseFET-based current sensing,“ 2011 IEEE International Solid-State Circuits Conference, San Francisco, CA, 2011, pp. 238-240.