Power Converter Design Optimization

Part 2: Converter Circuits

9 Capacitors

Capacitor Charge and Energy Density 395

Output Voltage Ripple 399

Power Capacitor Currents 401

L and Co Loss for Minimum Filter Size 409

10 Power-Switch and Driver Circuits

Power Switches 415

Diode Reverse Recovery 416

   Series L Reduction of Reverse Current 418

Darlington and BJT Switches 420

MOSFET Conduction Loss 428

MOSFET Voltage Breakdown 429

Optimal MOSFET Utilization 431

GaN and SiC Transistors 432

Circuit-Board Power-Bus Resonance 435

Power Driver Circuits 437

H-Bridge Switching and Sensing 439

Low-Side MOSFET Switching 444

Direct High-Side Drivers 451

Opto-Coupled High-Side Driver 454

High-Side Bootstrap Supply Circuits 455

High-Side Gate-Driver Supply 457

High-Side Driver Current Control 458

Transformer-Coupled Gate Drivers 461

Sampling Gate Driver 463

Clamping Gate Drivers 464

One-Sided Gate Driver 468

Innovatia Gate Driver 470

11 Sensing and Control Circuits

Low-Side Current Sensing 473

Sense Resistor Parasitic Inductance 478

Current-Sense Amplifiers 484

Sense-Resistor Board Layout 488

Current Transformer Sensing 489

Magnetic Saturation Sensing 495

Hall-Effect Device Sensing 499

High-Side Resistive Current Sensing 501

   Wilson Current Mirror 507

   High-Side ISN Example 508

TL431 Voltage Reference 512

   TL431 Circuit Model 514

   TL431 Parameter Derivations 518

      Output Resistance 518

      rout from Gm Currents 520

      Gm and ro from Test Data 522

   TL431 in Feedback Circuits 523

   TL431 Dynamics 526

   TL431 Output Impedance 531

Voltage Protection Circuits 535

Overcurrent Protection 542

   Passive OCP 543

   Transient and Steady-State OCP 546

Overtemperature Protection 556

Fan Control of Temperature 562

One-BJT Temperature Measurement 563

Voltage Positioning 567

PWM Voltage Control 568

PWM Current Control 579

Multicycle Burst Control 583

Converter Dual-Path Feedback Circuit 584

BPP Drive with Single PWM Outputs 585

Digital PWM Control 588

One-Comparator AST 592

Hysteresis Comparator Circuits 597

555 Timer 599

2-BJT Astable Timer 603

Starting Circuits 608

Boost PFC Control Supply 612

12 Thermal Design

Conductive Heat Transfer 614

Component Thermal Resistance 616

Convective Heat Transfer 618

Heat-Sink Circuit-Board Configurations 620

Forced Convection Cooling 624

Thermal Design Examples 626

Fan Driver Design 628

Radiative Heat Transfer 633

Thermal Dynamics 633

Thermal Feedback and Stability 636

Heat Sinks as Temperature Sensors 638

Thermoelectric Conversion 638

256 pages

 

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