Integrated Circuits and Systems group, IIT Madras

EE5325: Power Management Integrated Circuits(Jul-Nov 2022)

Instructor

Teaching Assistant

Classroom

  • ESB 207B

Schedule

F slot (Tue 5:00-5:50; Wed 11:00-11:50 ; Thu 9:00-9:50; Fri 8:00-8:50)

Course page on moodle

Registered students can login and see the course page at https://coursesnew.iitm.ac.in/. Resources, tutorials, exam schedules, discussion forum etc. can be accessed from the moodle page.

Teaching Assistants

Login to moodle at https://coursesnew.iitm.ac.in/ to post questions and contact faculty.

Evaluation

  • Assignments (10%)
  • Quiz-I (20%)
  • Quiz-II (20%)
  • Final Exam (30%)
  • Final Project (20%)

Objectives

To develop understanding of why power management circuits are needed in a VLSI system. What are different components of a power management system with focus on dc-dc converters. How to design a chip level dc-dc converter from a given system level specifications.

Course Contents

Introduction to Power Management and Voltage Regulators: Need of power management, power management applications, classification of power management, power delivery of a VLSI system, power conversion, discrete vs. integrated power management, types of voltage regulators (switching Vs linear regulators) and applications, converter’s performance parameters (voltage accuracy, power conversion efficiency, load regulation, line regulation, line and load transient response, settling time, voltage tracking), local Vs remote feedback, kelvin sensing, Point-of-Load (POL) regulators.

Linear Regulators: Bandgap Voltage Reference, Low Drop-Out Regulator (LDO), Source and sink regulators, shunt regulator, pass transistor, error amplifier, small signal model and stability analysis, compensation techniques, current limiting, power supply rejection ratio (PSRR), NMOS vs. PMOS regulator, current regulator.

Switching DC-DC Converters: Types (Buck, boost, buck-boost), power FETs, choosing L and C, PWM modulation, leading, trailing and dual edge modulation, Losses in switching converters, output ripple, voltage Vs current mode control, CCM and DCM modes, hysteretic control, switched capacitor dc-dc converters, Small signal model of dc-dc converter, loop gain analysis of un-compensated dc-dc converter, type-I, type-II and type-III compensation, compensation of a voltage mode dc-dc converter, compensation of a current mode dc-dc converter, Selecting topology, selecting switching frequency and external components, sizing power FETs, segmented power FET, designing building blocks (gate driver, PWM modulator, error amplifier, oscillator, ramp generator, feedback resistors), current sensing, PFM/PSM mode for light load, effect of parasitic on reliability and performance, current limit and short circuit protection, soft start control, chip level layout and placement guidelines, board level layout guidelines, EMI considerations.

Introduction to Advanced Topics in Power Management: Digitally controlled dc-dc converters, digitally controlled LDOs, time-based control for voltage regulators, adaptive compensation, dynamic voltage scaling (DVS), Single-Inductor Multiple-Outputs (SIMO) Converters, dc-dc converters for LED lighting, Li-ion battery charger.

References

  • Switch-Mode Power Supplies: SPICE Simulations and Practical Designs by Christophe P. Basso, BPB Publications, 2010
  • Fundamentals of Power Electronics, 2nd edition by Robert W. Erickson, Dragan Maksimovic, Springer (India) Pvt. Ltd, 2005
  • Power Management Techniques for Integrated Circuit Design By Ke-Horng Chen, Wiley-Blackwell, 2016

Pre-requisites

Attendance

Attendance will be strictly enforced.

Recorded Lectures

  • Lecture-1: handout video (Introduction to PMIC, course details)
  • Lecture-2: handout video-1 video-2 (dc-dc converter, types of dc-dc converter, linear vs switching regulator, selecting between linear and switching regulators, power management of a smartphone) (Note: lecture video was not recorded so link from NPTEL video lecture have been posted)
  • Lecture-3: handout video (Regulator's performance parameters-efficiency, accuracy, line and load regulation, line transient, Load transient, PSRR, remote vs. local feedback, point-of-load, droop compensation)
  • Lecture-4: handout video (Bandgap voltage reference, PTAT and CTAT voltage reference)
  • Lecture-5: handout video (Designing a bandgap reference using PTAT and CTAT)
  • Lecture-6: handout video (Current mode (sub-1V bandgap reference), generating multiple bandgap references, introduction to linear regulator-basic concept)
  • Lecture-7: handout video (Review of stability and feedback system - condition for instability, first order system, loop gain magnitude and phase, phase margin, second order system)
  • Lecture-8: handout-1 handout-2 video (Second order system-contd., relationship between location of loop gain (open loop) poles vs damping factor (closed loop poles)
  • Lecture-9: handout video (Damping factor vs. phase margin, loop gain analysis - breaking the loop)
  • Lecture-10: handout video (Finding poles of a linear regulator)
  • Lecture-11: handout video (Finding gain and poles of a linear regulator)
  • Lecture-12: handout video (Loop gain response of an uncompensated linear regulator, dominant pole compensation, miller effect)
  • Lecture-13: handout video (Miller compensation, pole splitting in miller compensation)
  • Lecture-14: handout video (R.H.P. zero due to miller compensation, techniques for mitigating the effect of R.H.P. zero, converting R.H.P. into L.H.P. using series or nulling resistor for pole-zero cancellation)
  • Lecture-15 handout video (Moving output pole at higher frequency by using NMOS LDO and flipped voltage follower-FVF, moving gate pole at high frequency by using source follower, pole-zero cancellation with feed-forward compensation, output impedance of linear regulator)
  • Lecture-16: handout video (Output impedance of linear regulator-contd., power supply rejection ratio-PSRR, techniques for improving PSRR)
  • Lecture-17: handout video (Sources of error in voltage regulators)
  • Lecture-18: handout video (Offset in error amplifier, techniques of offset correction/calibration)
  • Lecture-19: handout video (Digital LDO)
  • Lecture-20: handout video (Current limit and short circuit protection)

———– Quiz-I (02/09/2022) ———-

  • Lecture-21: handout video (Quiz-1 solutions, introduction to switching regulator)
  • Lecture-22: handout video (LC low pass filter, volt-second balance, inductor voltage and current waveforms, inductor ripple current, output voltage ripple, output voltage ripple vs duty cycle)
  • Lecture-23: handout video (Finding duty cycle under the resistive losses)
  • Lecture-24: handout video (Transfer model of a buck converter, efficiency of switching regulator, efficiency with only conduction or resistive losses, synchronous and non-synchronous converter, losses in switching dc-dc converter- conduction loss, gate switching loss)
  • Lecture-25: handout video (Losses in switching dc-dc converter-contd. - dead-time switching loss, hard switching loss, quiescent current loss, magnetic loss), power loss vs. load current, continuous and dis-continuous conduction modes - CCM and DCM, voltage transfer ratio in DCM)
  • Lecture-26: handout video (DCM operation-finding Iload for CCM-DCM boundary, finding D for a given Iload, finding Fsw for min. Ton i.e. PFM operation)
  • Lecture-27: handout video (Pulse width modulation - trailing, leading and dual edge modulation, PWM delay, dc-dc converter control techniques, voltage mode vs. current mode control, small signal loop gain analysis using continuous time model, loop gain analysis of a uncompensated dc-dc converter, compensating a dc-dc converter)
  • Lecture-28: handout video (Type-I or integral compensation, designing type-I compensator using gm-C)
  • Lecture-29: handout video (Designing type-I compensator using opamp-RC, pros and cons of type-I compensation, type-II compensation)
  • Lecture-30: handout video (type-II compensation-contd., compensation using type-II and output ESR zero, design type-II compensator using gm-C)
  • Lecture-31: handout video ((Designing type-II compensator using opamp-RC, type-III compensator, type-III to PID transformation)
  • Lecture-32: handout (refer to NPTEL lecture for video) (Adding high frequency poles for noise suppression, feed-forward line compensation)
  • Lecture-33: handout video (Designing a buck converter, specifications, budgeting power loss, sizing power MOSFETs)
  • Lecture-34: handout video (Estimating switching losses, estimating the values of L & C)
  • Lecture-35: handout video (Inductor limited load transient response, bandwidth limited load transient response, re-calculating the output capacitor based on load transient)

———– Quiz-II (07/10/2022) ———-

  • Lecture-36: handout video (selecting inductor, inductor saturation and rated currents, selecting capacitor)
  • Lecture-37: handout video (Gate driver - non-overlap clock generator, sizing clock buffer, ramp generator, shifting common mode of ramp generator)
  • Lecture-38: handout video (Designing a dual edge modulator, oscillator as a triangular wave generator, design considerations of an error amplifier)
  • Lecture-39: handout1 handout2 video ( Pulse skip modulation (PSM) and pulse frequency modulation (PFM), implementing DCM operation, designing a zero cross comparator/detector)
  • Lecture-40: handout video (Current mode control - basic concept, voltage vs. current mode control, types of current mode control - peak, valley and emulated)
  • Lecture-41: handout1 handout2 video (Current mode control-contd: sub-harmonic oscillations and current loop instability, ramp/slope compensation, adaptive slope compensation, introduction to non-linear control, hysteretic dc-dc converter)
  • Lecture-42: handout video (Stabilising a hysteretic converter using Resr, finding the value of Resr, finding the switching frequency)
  • Lecture-43: handout video (Current mode hysteretic converter, using R-C as ripple generator, error correction in current mode converter, controlling switching frequency of a hysteretic converter, fixed frequency hysteretic converter, constant ON/OFF time control)
  • Lecture-44: handout1 handout2 video (Boost converter, Buck-Boost converter, tri-mode buck boost converter, issue with mode transition, transition boundary condition, digital control in buck-boost mode)
  • Lecture-45: handout1 handout2 video (Switched capacitor dc-dc converter, application as cascaded switched capacitor and inductive dc-dc converter or LDO, basic concept, H-Bridge chargepump for 2x boost, 1/2 buck and inverting application, regulating output using PFM/Burst mode, efficiency of a SC dc-dc converter)
  • Lecture-46: handout (Current sensing techniques in dc-dc converters)
  • Lecture-47: handout video (Layout techniques for Analog and Power Management ICs)

——end of topics for endsem (21/11/2022)———–

  • Lecture-48: handout video (Digitally controlled dc-dc converter)
  • Lecture-49: handout video (Multi-phase dc-dc converter, single inductor multiple output dc-dc converter)
  • Lecture-50: handout1 handout2 video (Dynamic voltage and frequency scale, power management for displays)
  • Refer to week-11 & 12 lectures of NPTEL_PMIC for time-based dc-dc converter and battery charger.

You can find lectures from previous years below:

NPTEL Lectures: