Infineon XMC Series, Application Manual

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Introduction to Digital Power Conversion
XMC4000/1000 Family
Table of Contents
Application Guide 4 V1.0, 2015-01
Table of Contents
1 About this document ......................................................................................................................... 6
1.1 Scope and Purpose .............................................................................................................................. 6
1.2 Intendend Audience ............................................................................................................................. 6
2 Comparison of Power Conversion Methods ................................................................................... 7
2.1 What is Power Conversion ................................................................................................................... 7
2.2 Why Power Conversion ........................................................................................................................ 7
2.3 Methods of Power Conversion ............................................................................................................. 7
2.3.1 Linear Mode Power Conversion ..................................................................................................... 7
2.3.2 Switch Mode Power Conversion .................................................................................................... 9
2.3.2.1 Analog Switch Mode Controllers ............................................................................................. 11
2.3.2.2 Digital Switch Mode Controllers .............................................................................................. 11
2.3.2.3 ASIC controller versus MCU / DSP / DSC controllers ............................................................ 12
2.4 Infineon XMC-families for Switch Mode Power Control ..................................................................... 13
2.4.1 Power Conversion Oriented Peripheral Features ........................................................................ 14
2.4.1.1 Sensing ................................................................................................................................... 14
2.4.1.2 Stability and Software ............................................................................................................. 14
2.4.1.3 Modulation .............................................................................................................................. 14
2.4.1.4 PWM Generation .................................................................................................................... 15
3 Converter Topologies ...................................................................................................................... 16
3.1 Buck ................................................................................................................................................... 17
3.2 Boost .................................................................................................................................................. 18
3.3 PFC .................................................................................................................................................... 19
3.4 Phase-Shift Full-Bridge (PSFB) ......................................................................................................... 21
3.5 LLC (Inductor-Inductor-Capacitor) ..................................................................................................... 22
3.6 Generic Digital Power Converter ........................................................................................................ 23
4 PWM Generation............................................................................................................................... 24
4.1 Single Channel ................................................................................................................................... 24
4.2 Single Channel with Complementary Outputs ................................................................................... 24
4.3 Dual Channel with Complementary Outputs with Dead-Time, using CCU8 ...................................... 25
4.4 Dual Channel with Complementary Outputs with Dead-Time, using CCU4 ...................................... 25
4.5 ON/OFF Control ................................................................................................................................. 27
4.6 Fixed ON-Time (FOT) ........................................................................................................................ 27
4.7 Fixed ON-Time with Frequency Limit Control .................................................................................... 28
4.8 Fixed Off-Time (FOFFT) .................................................................................................................... 31
4.9 Phase Shift Control ............................................................................................................................ 32
4.10 Fixed Phase-Shift ............................................................................................................................... 32
4.10.1 Center Aligned Mode ................................................................................................................... 32
4.10.2 Edge Aligned Mode ...................................................................................................................... 33
4.10.3 Interleave ..................................................................................................................................... 34
4.11 Variable Phase-Shift .......................................................................................................................... 35
4.11.1 Power Conversion Control Example ............................................................................................ 37
4.11.2 Zero-Voltage Switching (ZVS) Control ......................................................................................... 38
4.12 Adding High Resolution Channel (HRC)
– HRPWM .......................................................................... 39
4.12.1 PWM Dead-Time Compensation ................................................................................................. 40
4.13 Half-Bridge LLC Control using ½ CCU4............................................................................................. 41
4.14 Half-Bridge LLC Control - Synchronous Rectification using CCU4 ................................................... 42
4.15 Full-Bridge LLC Control Using HRC
– Synchronous Rectification ..................................................... 43
4.16 Full-Bridge LLC Control
– Synchronous Rectification Using HRC ..................................................... 44
5 Sensing ............................................................................................................................................. 46
5.1 Analog Signal Sensing ....................................................................................................................... 46
5.1.1 Level Crossing Detection, Fast Compare mode .......................................................................... 46
5.1.2 PWM with Fast Compare mode Hysteretic Switching ................................................................. 47
5.1.3 Peak Control Using Fast Compare mode .................................................................................... 48
5.1.4 ZCD Control Using Fast Compare mode ..................................................................................... 49