Data Structures and Algorithms Made Easy 5th

Chapter 1: Data Converter History ........................................................................................3 Section 1-1: Early History .............................................................................................................5 The Early Years: Telegraph to Telephone .......................................................................................... 6 The Invention of PCM ....................................................................................................................... 8 The Mathematical Foundations of PCM ........................................................................................... 9 The PCM Patents of Alec Harley Reeves ........................................................................................ 10 PCM and the Bell System: World War II through 1948 .................................................................. 11 Op Amps and Regenerative Repeaters: Vacuum Tubes to Solid-State ............................................ 13 Section 1-2: Data Converters of the 1950s and 1960s ...................................................................19 Commercial Data Converters: 1950s ............................................................................................... 19 Commercial Data Converter History: 1960s ................................................................................... 20 Data Converter Architectures .......................................................................................................... 23 Section 1-3: Data Converters of the 1970s ...................................................................................27 Monolithic Data Converters of the 1970s ........................................................................................28 Bipolar Process IC DACs of the 1970s ...........................................................................................28 CMOS IC DACs of the 1970s ......................................................................................................... 29 Monolithic ADCs of the 1970s ........................................................................................................ 31 Hybrid Data Converters of the 1970s .............................................................................................. 32 Modular Data Converters of the 1970s ............................................................................................ 35 Section 1-4: Data Converters of the 1980s ...................................................................................39 Monolithic DACs of the 1980s ........................................................................................................ 40 Monolithic ADCs of the 1980s ........................................................................................................ 41 Monolithic Flash ADCs of the 1980s .............................................................................................. 42 Hybrid and Modular DACs and ADCs of the 1980s ....................................................................... 42 Section 1-5: Data Converters of the 1990s ...................................................................................45 Monolithic DACs of the 1990s ........................................................................................................ 46 Monolithic ADCs of the 1990s ........................................................................................................ 48 Hybrid and Modular DACs and ADCs of the 1990s ....................................................................... 52 Section 1-6: Data Converters of the 2000s ...................................................................................53 Chapter 2: Fundamentals of Sampled Data Systems ...............................................................57 Section 2-1: Coding and Quantizing .............................................................................................57 Unipolar Codes ................................................................................................................................ 59 Gray Code ........................................................................................................................................ 61 Bipolar Codes .................................................................................................................................. 62 TLFeBOOKvi Contents Complementary Codes .................................................................................................................... 65 DAC and ADC Static Transfer Functions and DC Errors ............................................................... 66 Section 2-2: Sampling Theory ......................................................................................................73 The Need for a Sample-and-Hold Amplifi er (SHA) Function ........................................................ 74 The Nyquist Criteria ........................................................................................................................ 76 Baseband Antialiasing Filters .......................................................................................................... 78 Undersampling (Harmonic Sampling, Bandpass Sampling, IF Sampling, Direct IF-to-Digital Conversion) ................................................................................................. 80 Antialiasing Filters in Undersampling Applications ....................................................................... 81 Section 2-3: Data Converter AC Errors ........................................................................................83 Theoretical Quantization Noise of an Ideal N-Bit Converter .......................................................... 83 Noise in Practical ADCs .................................................................................................................. 88 Equivalent Input Referred Noise .................................................................................................... 89 Noise-Free (Flicker-Free) Code Resolution ................................................................................... 89 Dynamic Performance of Data Converters ...................................................................................... 90 Integral and Differential Nonlinearity Distortion Effects ................................................................ 90 Harmonic Distortion, Worst Harmonic, Total Harmonic Distortion (THD), Total Harmonic Distortion Plus Noise (THD + N) ...................................................................... 91 Signal-to-Noise-and-Distortion Ratio (SINAD), Signal-to-Noise Ratio (SNR), and Effective Number of Bits (ENOB) ....................................................................................... 91 Analog Bandwidth ........................................................................................................................... 92 Spurious Free Dynamic Range (SFDR) .......................................................................................... 93 Two-Tone Intermodulation Distortion (IMD) ................................................................................. 94 Second- and Third-Order Intercept Points, 1 dB Compression Point ............................................. 95 Multitone Spurious Free Dynamic Range ....................................................................................... 96 Wideband CDMA (WCDMA) Adjacent Channel Power Ratio (ACPR) and Adjacent Channel Leakage Ratio (ADLR) ................................................................................................. 97 Noise Power Ratio (NPR) ................................................................................................................ 98 Noise Factor (F) and Noise Figure (NF) ....................................................................................... 100 Aperture Time, Aperture Delay Time, and Aperture Jitter ........................................................... 106 A Simple Equation for the Total SNR of an ADC ........................................................................ 108 ADC Transient Response and Overvoltage Recovery ................................................................... 109 ADC Sparkle Codes, Metastable States, and Bit Error Rate (BER) ............................................. 111 DAC Dynamic Performance ......................................................................................................... 115 DAC Settling Time ................................................................................................................. 115 Glitch Impulse Area ............................................................................................................... 116 DAC SFDR and SNR ............................................................................................................. 117 Measuring DAC SNR with an Analog Spectrum Analyzer .................................................... 118 DAC Output Spectrum and sin (x)/x Frequency Roll-off ....................................................... 119 Oversampling Interpolating DACs ......................................................................................... 120 Section 2-4: General Data Converter Specifi cations ......................................................................123 Overall Considerations .................................................................................................................. 123 Logic Interface Issues .................................................................................................................... 124 Data Converter Logic: Timing and other Issues ............................................................................ 125 Section 2-5: Defi ning the Specifi cations .......................................................................................127 TLFeBOOKvii Contents Chapter 3: Data Converter Architectures ............................................................................147 Section 3-1: DAC Architectures .................................................................................................147 DAC Output Considerations .......................................................................................................... 148 Basic DAC Structures .................................................................................................................... 149 The Kelvin Divider (String DAC) .......................................................................................... 149 Thermometer (Fully-Decoded) DACs .................................................................................... 151 Binary-Weighted DACs .......................................................................................................... 153 R-2R DACs ............................................................................................................................. 155 Segmented DACs .................................................................................................................... 159 Oversampling Interpolating DACs ................................................................................................ 163 Multiplying DACs ......................................................................................................................... 164 Intentionally Nonlinear DACs ....................................................................................................... 164 Counting, Pulsewidth-Modulated (PWM) DACs .......................................................................... 167 Cyclic Serial DACs ........................................................................................................................ 167 Other Low Distortion Architectures .............................................................................................. 169 DAC Logic Considerations ............................................................................................................ 170 Section 3-2: ADC Architectures .................................................................................................175 The Comparator: A 1-Bit ADC ...................................................................................................... 178 High Speed ADC Architectures ..................................................................................................... 180 Flash Converters ..................................................................................................................... 180 Successive Approximation ADCs ........................................................................................... 185 Subranging, Error Corrected, and Pipelined ADCs ............................................................... 190 Serial Bit-Per-Stage Binary and Gray Coded (Folding) ADCs ............................................. 203 Counting and Integrating ADC Architectures ............................................................................... 211 A. H. Reeves’ 5-Bit Counting ADC ....................................................................................... 211 Charge Run-Down ADC ......................................................................................................... 212 Ramp Run-Up ADC ............................................................................................................... 212 Tracking ADC ........................................................................................................................ 213 Voltage-to-Frequency Converters (VFCs) .............................................................................. 214 Dual Slope/Multislope ADCs ................................................................................................. 218 Optical Converters ......................................................................................................................... 220 Resolver-to-Digital Converters (RDCs) and Synchros .................................................................. 221 Section 3-3: Sigma-Delta Converters ..........................................................................................231 Historical Perspective .................................................................................................................... 231 Sigma-Delta (Σ-∆) or Delta-Sigma (∆-Σ)? ................................................................................... 234 Basics of Sigma-Delta ADCs ........................................................................................................ 235 Idle Tone Considerations ............................................................................................................... 240 Higher Order Loop Considerations ............................................................................................... 241 Multibit Sigma-Delta Converters .................................................................................................. 242 Digital Filter Implications ............................................................................................................. 243 Multistage Noise Shaping (MASH) Sigma-Delta Converters ....................................................... 244 High Resolution Measurement Sigma-Delta ADCs ...................................................................... 245 Sigma-Delta DACs ........................................................................................................................ 249 Chapter 4: Data Converter Process Technology ....................................................................257 Section 4-1: Early Processes ......................................................................................................257 Vacuum Tube Data Converters ...................................................................................................... 257 TLFeBOOKviii Contents Solid State, Modular, and Hybrid Data Converters ....................................................................... 259 Calibration Processes ..................................................................................................................... 262 Section 4-2: Modern Processes ...................................................................................................265 Bipolar Processes ........................................................................................................................... 265 Thin Film Resistor Processes ........................................................................................................ 265 Complementary Bipolar (CB) Processes ....................................................................................... 266 CMOS Processes ........................................................................................................................... 266 Data Converter Processes and Architectures ................................................................................. 268 Section 4-3: Smart Partitioning .................................................................................................273 When Complete Integration Isn’t the Optimal Solution ................................................................ 273 Why Smart Partitioning is Necessary ........................................................................................... 276 What’s Changing? ......................................................................................................................... 277 Chapter 5: Testing Data Converters ...................................................................................283 Section 5-1: Testing DACs ........................................................................................................283 Static DAC Testing ........................................................................................................................ 283 End-Point Errors ..................................................................................................................... 284 Linearity Errors ...................................................................................................................... 286 Superposition and DAC Errors ............................................................................................... 286 Measuring DAC DNL and INL Using Superposition ............................................................ 287 Measuring DAC INL and DNL Where Superposition Does Not Hold .................................. 290 Testing DACs for Dynamic Performance ...................................................................................... 292 Settling Time .......................................................................................................................... 292 Glitch Impulse Area ............................................................................................................... 293 Oscilloscope Measurement of Settling Time and Glitch Impulse Area ................................ 294 Distortion Measurements ....................................................................................................... 295 Section 5-2: Testing ADCs ........................................................................................................303 A Brief Historical Overview of Data Converter Specifi cations and Testing ................................. 303 Static ADC Testing ........................................................................................................................ 304 Back-to-Back Static ADC Testing .......................................................................................... 306 Crossplot Measurements of ADC Linearity ........................................................................... 309 Servo-Loop Code Transition Test ........................................................................................... 310 Computer-Based Servo-Loop ADC Tester ............................................................................. 311 Histogram (Code Density) Test with Linear Ramp Input ...................................................... 312 Dynamic ADC Testing ................................................................................................................... 317 Manual “Back-to-Back” Dynamic ADC Testing ................................................................... 317 Measuring Effective Number of Bits (ENOB) Using Sinewave Curve Fitting ...................... 320 FFT Basics .............................................................................................................................. 322 FFT Test Setup Confi guration and Measurements ................................................................. 329 Verifying the FFT Accuracy ................................................................................................... 335 Generating Low Distortion Sinewave Inputs ......................................................................... 335 Noise Power Ratio (NPR) Testing .......................................................................................... 337 Measuring ADC Aperture Jitter Using the Locked-Histogram Test Method ......................... 338 Measuring Aperture Delay Time ............................................................................................ 340 Measuring ADC Aperture Jitter Using FFTs .......................................................................... 340 Measuring ADC Analog Bandwidth Using FFTs .................................................................. 342 Settling Time .......................................................................................................................... 343 TLFeBOOKix Contents Overvoltage Recovery Time ................................................................................................... 344 Video Testing, Differential Gain and Differential Phase ........................................................ 344 Bit Error Rate (BER) Tests ..................................................................................................... 348 Chapter 6: Interfacing to Data Converters ...........................................................................359 Section 6-1: Driving ADC Analog Inputs .....................................................................................359 Amplifer DC and AC Performance Considerations ...................................................................... 361 Rail-Rail Input Stages .................................................................................................................... 362 Output Stages ................................................................................................................................. 365 Gain and Level-Shifting Circuits Using Op Amps ........................................................................ 367 Op Amp AC Specifi cations and Data Converter Requirements .................................................... 369 Driving High Resolution Σ-∆ Measurement ADCs ....................................................................... 371 Driving Single-Ended Input Single-Supply 1.6 V to 3.6 V Successive Approximation ADCs ..... 372 Driving Single-Supply ADCs with Scaled Inputs ......................................................................... 373 Driving Differential Input CMOS Switched Capacitor ADCs ...................................................... 374 Single-Ended Drive Circuits for Differential Input CMOS ADCs ................................................ 376 Differential Input ADC Drivers ..................................................................................................... 378 Driving ADCs with Differential Amplifi ers .................................................................................. 382 Dual Op Amp Drivers .................................................................................................................... 383 Fully Integrated Differential Amplifi er Drivers ............................................................................. 384 Driving Differential Input ADCs with Integrated Differential Drivers ......................................... 387 Section 6-2: ADC and DAC Digital Interfaces(and Related Issues) ................................................397 Power-On Initialization of Data Converters ................................................................................. 397 Initialization of Data Converter Internal Control Registers ........................................................... 398 Low Power, Sleep, and Standby Modes ....................................................................................... 398 Single-Shot Mode, Burst Mode, and Minimum Sampling Frequency .......................................... 399 ADC Digital Output Interfaces ...................................................................................................... 400 ADC Serial Output Interfaces ....................................................................................................... 400 ADC Serial Interface to DSPs ...................................................................................................... 403 ADC Parallel Output Interfaces ..................................................................................................... 405 DAC Digital Input Interfaces ......................................................................................................... 408 DAC Serial Input Interfaces to DSPs ............................................................................................ 410 DAC Parallel Input Interfaces to DSPs .......................................................................................... 411 Section 6-3: Buffering DAC Analog Outputs ...............................................................................415 Differential to Single-Ended Conversion Techniques ................................................................... 416 Single-Ended Current-to-Voltage Conversion ............................................................................... 418 Differential Current-to-Differential Voltage Conversion ............................................................... 420 An Active Low-Pass Filter for Audio DAC .................................................................................. 420 Section 6-4: Data Converter Voltage References ..........................................................................423 Section 6-5: Sampling Clock Generation .....................................................................................427 Oscillator Phase Noise and Jitter ................................................................................................... 430 “Hybrid” Clock Generators ........................................................................................................... 437 Driving Differential Sampling Clock Inputs ................................................................................. 438 Sampling Clock Summary ............................................................................................................. 439 Chapter 7: Data Converter Support Circuits ........................................................................443 Section 7-1: Voltage References .................................................................................................443 Precision Voltage References ........................................................................................................ 443 TLFeBOOKx Contents Types of Voltage References .......................................................................................................... 444 Bandgap References ............................................................................................................... 446 Buried Zener References ........................................................................................................ 451 XFET References ................................................................................................................... 452 Voltage Reference Specifi cations .................................................................................................. 455 Tolerance ................................................................................................................................ 455 Drift ........................................................................................................................................ 455 Supply Range ......................................................................................................................... 456 Load Sensitivity ...................................................................................................................... 456 Line Sensitivity ....................................................................................................................... 457 Noise ....................................................................................................................................... 457 Scaled References .......................................................................................................................... 459 Voltage Reference Pulse Current Response ................................................................................... 460 Low Noise References for High Resolution Converters ............................................................... 462 Section 7-2: Low Dropout Linear Regulators ...............................................................................465 Linear Voltage Regulator Basics .................................................................................................... 465 Pass Devices and their Associated Trade Offs ............................................................................... 468 Low Dropout Regulator Architectures .......................................................................................... 472 The anyCAP Low Dropout Regulator Family ............................................................................... 475 Design Features Related to DC Performance ......................................................................... 475 Design Features Related to AC Performance ......................................................................... 476 A Basic Pole-Splitting Topology ............................................................................................ 477 The anyCAP Pole-Splitting Topology .................................................................................... 477 The anyCAP LDO series devices ........................................................................................... 478 Functional Diagram and Basic 50 mA LDO Regulator ......................................................... 479 LDO Regulator Thermal Considerations ............................................................................... 481 LDO Regulator Controllers ........................................................................................................... 485 Regulator Controller Differences ........................................................................................... 485 A Basic 5 V/1 A LDO Regulator Controller .......................................................................... 486 Selecting the Pass Device ....................................................................................................... 487 Thermal Design ...................................................................................................................... 488 Sensing Resistors for LDO Controllers .................................................................................. 489 PCB Layout Issues ................................................................................................................. 490 A 2.8 V/8 A LDO Regulator Controller ................................................................................. 491 Section 7-3: Analog Switches and Multiplexers ............................................................................493 CMOS Switch Basics .................................................................................................................... 494 Error Sources in the CMOS Switch ............................................................................................... 496 Applying the Analog Switch ........................................................................................................ 504 1 GHz CMOS Switches ................................................................................................................. 508 Video Switches and Multiplexers .................................................................................................. 508 Video Crosspoint Switches ............................................................................................................ 511 Digital Crosspoint Switches .......................................................................................................... 512 Switch and Multiplexer Families from Analog Devices ................................................................ 512 Parasitic Latchup in CMOS Switches and Muxes ......................................................................... 512 Section 7-4: Sample-and-Hold Circuits ........................................................................................519 Introduction and Historical Perspective ........................................................................................ 519 TLFeBOOKxi Contents Basic SHA Operation .................................................................................................................... 521 Track Mode Specifi cations ............................................................................................................ 522 Track-to-Hold Mode Specifi cations .............................................................................................. 522 Hold Mode Specifi cations ............................................................................................................. 526 Hold-to-Track Transition Specifi cations ....................................................................................... 528 SHA Architectures ......................................................................................................................... 529 Internal SHA Circuits for IC ADCs ............................................................................................... 531 SHA Applications .......................................................................................................................... 533 Chapter 8: Data Converter Applications .............................................................................539 Section 8-1: Precision Measurement and Sensor Conditioning ........................................................539 Applications of Precision Measurement Σ-∆ ADCs ...................................................................... 540 Weigh Scale Design Analysis Using the AD7730 ADC ................................................................ 544 Thermocouple Conditioning Using the AD7793 ........................................................................... 549 Direct Digital Temperature Measurements .................................................................................... 551 Microprocessor Substrate Temperature Sensors ............................................................................ 555 Applications of ADCs in Power Meters ........................................................................................ 558 Section 8-2: Multichannel Data Acquisition Systems .....................................................................563 Data Acquisition System Confi gurations ....................................................................................... 563 Multiplexing .................................................................................................................................. 564 Filtering Considerations in Data Acquisition Systems .................................................................. 567 Complete Data Acquisition Systems on a Chip ............................................................................. 568 Multiplexing Inputs to Σ-∆ ADCs ................................................................................................. 570 Simultaneous Sampling Systems ................................................................................................... 572 Data Distribution Systems ............................................................................................................ 574 Data Distribution Using an Infi nite Sample-and-Hold .................................................................. 578 Section 8-3: Digital Potentiometers ............................................................................................581 Modern Digital Potentiometers in Tiny Packages ......................................................................... 582 Digital Potentiometers with Nonvolatile Memory ........................................................................ 584 One-Time Programmable (OTP) Digital Potentiometers .............................................................. 585 Digital Potentiometer AC Considerations ..................................................................................... 586 Application Examples ................................................................................................................... 587 Section 8-4: Digital Audio .........................................................................................................591 Sampling Rate and THD + N Requirements for Digital Audio ..................................................... 592 Overall Trends in Digital Audio ADCs and DACs ........................................................................ 595 Voiceband Codecs .......................................................................................................................... 596 High Performance Audio ADCs and DACs in Separate Packages ................................................ 597 High Performance Multichannel Audio Codecs and DACs .......................................................... 600 Sample Rate Converters ................................................................................................................ 602 Section 8-5: Digital Video and Display Electronics .......................................................................607 Digital Video .................................................................................................................................. 607 Digital Video Formats ............................................................................................................ 608 Serial Data Interfaces ............................................................................................................. 612 Digital Video ADCs and DACs: Decoders, and Encoders ..................................................... 612 Specifi cations for Video Decoders and Encoders ................................................................... 614 Display Electronics ........................................................................................................................ 615 Flat Panel Display Electronics ............................................................................................... 619 TLFeBOOKxii Contents CCD Imaging Electronics ...................................................................................................... 622 Touchscreen Digitizers ........................................................................................................... 627 Section 8-6: Software Radio and IF Sampling ..............................................................................633 Evolution of Software Radio ......................................................................................................... 634 A Receiver Using Digital Processing at Baseband ........................................................................ 635 Narrowband IF-Sampling Digital Receivers ................................................................................. 636 Wideband IF-Sampling Digital Receivers ..................................................................................... 639 Increasing ADC Dynamic Range Using Dither ............................................................................. 649 Wideband Radio Transmitter Considerations ................................................................................ 655 Cellular Telephone Handsets ......................................................................................................... 659 The Role of ADCs and DACs in Cellular Telephone Handsets ..................................................... 661 SoftFone® and Othello Radio Chipsets from Analog Devices ..................................................... 662 Time-Interleaved IF Sampling ADCs with Digital Post-Processors ............................................. 667 Advanced Digital Post Processing ................................................................................................. 671 Advanced Filter Bank (AFB) ........................................................................................................ 672 AFB Design Example: The AD12400 12-Bit, 400 MSPS ADC ................................................... 673 Section 8-7: Direct Digital Synthesis (DDS) ................................................................................677 Introduction to DDS ...................................................................................................................... 677 Aliasing in DDS Systems .............................................................................................................. 681 Frequency Planning in DDS Systems ............................................................................................ 682 Modern Integrated DDS Systems .................................................................................................. 684 Section 8-8: Precision Analog Microcontrollers ............................................................................693 Characteristics of the MicroConverter Product Family ................................................................. 694 Some Σ-∆ MicroConverter Applications ....................................................................................... 700 ADuC7xxx MicroConverter Products Based on the ARM7 Processor Core ................................ 702 Chapter 9: Hardware Design Techniques .............................................................................709 Section 9-1: Passive Components ...............................................................................................711 Capacitors ...................................................................................................................................... 711 Dielectric Absorption ............................................................................................................. 712 Capacitor Parasitics and Dissipation Factor ........................................................................... 714 Tolerance, Temperature, and Other Effects ............................................................................ 715 Assemble Critical Components Last ...................................................................................... 715 Resistors and Potentiometers ......................................................................................................... 718 Resistor Parasitics ................................................................................................................... 720 Thermoelectric Effects ........................................................................................................... 720 Voltage Sensitivity, Failure Mechanisms, and Aging ............................................................. 722 Resistor Excess Noise ............................................................................................................ 723 Potentiometers ........................................................................................................................ 723 Inductance ...................................................................................................................................... 725 Stray Inductance ..................................................................................................................... 725 Mutual Inductance .................................................................................................................. 725 Ringing ................................................................................................................................... 728 Parasitic Effects in Inductors .................................................................................................. 728 Q or “Quality Factor” ............................................................................................................. 729 Don’t Overlook Anything .............................................................................................................. 729 TLFeBOOKxiii Contents Section 9-2: PC Board Design Issues ..........................................................................................733 Resistance of Conductors .............................................................................................................. 733 Voltage Drop in Signal Leads—“Kelvin” Feedback ..................................................................... 735 Signal Return Currents .................................................................................................................. 736 Grounding in Mixed Analog/Digital Systems ............................................................................... 737 Ground and Power Planes ...................................................................................................... 738 Double-Sided versus Multilayer Printed Circuit Boards ........................................................ 739 Multicard Mixed-Signal Systems ........................................................................................... 740 Separating Analog and Digital Grounds ................................................................................. 740 Grounding and Decoupling Mixed-Signal ICs with Low Digital Currents ........................... 742 Treat the ADC Digital Outputs with Care .............................................................................. 743 Sampling Clock Considerations ............................................................................................. 744 The Origins of the Confusion about Mixed-Signal Grounding: Applying Single-Card Grounding Concepts to Multicard Systems ...................................................................... 746 Summary: Grounding Mixed-Signal Devices with Low Digital Currents in a Multicard System ............................................................................................................... 747 Summary: Grounding Mixed-Signal Devices with High Digital Currents in a Multicard System ............................................................................................................... 748 Grounding DSPs with Internal Phase-Locked Loops ............................................................. 748 Grounding Summary .............................................................................................................. 749 Some General PC Board Layout Guidelines for Mixed-Signal Systems ...................................... 750 Skin Effect .............................................................................................................................. 751 Transmission Lines ................................................................................................................. 753 Be Careful With Ground Plane Breaks ................................................................................... 753 Ground Isolation Techniques .................................................................................................. 754 Static PCB Effects .................................................................................................................. 756 Sample MINIDIP and SOIC Op Amp PCB Guard Layouts .................................................. 758 Dynamic PCB Effects ............................................................................................................ 760 Stray Capacitance ................................................................................................................... 761 Capacitive Noise and Faraday Shields ................................................................................... 762 The Floating Shield Problem .................................................................................................. 762 Buffering ADCs Against Logic Noise ................................................................................... 763 Section 9-3: Analog Power Supply Systems ..................................................................................767 Linear IC Regulation ..................................................................................................................... 768 Some Linear Voltage Regulator Basics .................................................................................. 768 Pass Devices .......................................................................................................................... 770 ±15 V Regulator Using Adjustable Voltage ICs ..................................................................... 770 Low Dropout Regulator Architectures ................................................................................... 771 Fixed-Voltage, 50/100/200/500/1000/1500 mA LDO Regulators ......................................... 772 Adjustable Voltage, 200 mA LDO Regulator ......................................................................... 774 Charge-Pump Voltage Converters ................................................................................................. 775 Regulated Output Charge-Pump Voltage Converters .................................................................... 776 Linear Post Regulator for Switching Supplies .............................................................................. 778 Grounding Linear and Switching Regulators ................................................................................ 779 Power Supply Noise Reduction and Filtering ............................................................................... 782 Capacitors ............................................................................................................................... 782 TLFeBOOKxiv Contents Ferrites .................................................................................................................................... 786 Card Entry Filter ..................................................................................................................... 787 Rail Bypass/Distribution Filter ............................................................................................... 788 Local High Frequency Bypass/Decoupling ............................................................................ 789 Section 9-4: Overvoltage Protection ...........................................................................................793 In-Circuit Overvoltage Protection ................................................................................................. 793 General Input Common Mode Limitations ................................................................................... 793 Clamping Diode Leakage .............................................................................................................. 795 A Flexible Voltage Follower Protection Circuit ........................................................................... 796 Common-Mode Overvoltage Protection Using CMOS Channel Protectors ................................. 797 CM Overvoltage Protection Using High CM Voltage In Amp ...................................................... 798 Inverting Mode Op Amp Protection Schemes ............................................................................... 800 Amplifi er Output Voltage Phase-Reversal ..................................................................................... 800 An Output Phase-Reversal Do-it-Yourself Test ...................................................................... 802 Fixes for Output Phase–Reversal ........................................................................................... 802 Input Differential Protection ......................................................................................................... 803 Protecting In Amps Against Overvoltage ...................................................................................... 804 Overvoltage Protection Using CMOS Channel Protectors ............................................................ 808 Digital Isolators ............................................................................................................................. 810 Out-of-Circuit Overvoltage Protection .......................................................................................... 813 ESD Models and Testing ............................................................................................................... 817 Section 9-5: Thermal Management .............................................................................................823 Thermal Basics .............................................................................................................................. 823 Heat Sinking .................................................................................................................................. 825 Data Converter Thermal Considerations ....................................................................................... 829 Section 9-6: EMI/RFI Considerations .........................................................................................833 EMI/RFI Mechanisms ................................................................................................................... 834 EMI Noise Sources ........................................................................................................................ 834 EMI Coupling Paths ...................................................................................................................... 834 Noise Coupling Mechanisms ......................................................................................................... 834 Reducing Common-Impedance Noise ........................................................................................... 835 Noise Induced by Near-Field Interference .................................................................................... 836 Reducing Capacitance-Coupled Noise .......................................................................................... 836 Reducing Magnetically-Coupled Noise ........................................................................................ 837 Passive Components: Your Arsenal Against EMI .......................................................................... 838 Reducing System Susceptibility to EMI ........................................................................................ 839 A Review of Shielding Concepts ................................................................................................... 839 General Points on Cables and Shields ........................................................................................... 842 Input-Stage RFI Rectifi cation Sensitivity ...................................................................................... 846 Background: Op Amp and In Amp RFI Rectifi cation Sensitivity Tests ................................. 846 An Analytical Approach: BJT RFI Rectifi cation .................................................................... 847 An Analytical Approach: FET RFI Rectifi cation .................................................................. 848 Reducing RFI Rectifi cation Within Op amp and In Amp Circuits ......................................... 849 Op Amp Inputs ............................................................................................................................. 849 In Amp Inputs ................................................................................................................................ 850 Amplifi er Outputs and EMI/RFI ................................................................................................... 852 TLFeBOOKxv Contents Printed Circuit Board Design for EMI/RFI Protection .................................................................. 852 Choose Logic Devices Carefully .................................................................................................. 853 Design PCBs Thoughtfully ............................................................................................................ 853 Designing Controlled Impedances Traces on PCBs ..................................................................... 854 Microstrip PCB Transmission Lines ............................................................................................. 855 Some Microstrip Guidelines .......................................................................................................... 855 Symmetric Stripline PCB Transmission Lines .............................................................................. 856 Some Pros and Cons of Embedding Traces ................................................................................... 857 Dealing with High-Speed Logic .................................................................................................... 858 Section 9-7: Low Voltage Logic Interfacing ..................................................................................867 Voltage Tolerance and Voltage Compliance .................................................................................. 870 Interfacing 5 V Systems to 3.3 V Systems using NMOS FET “Bus Switches” ............................ 871 3.3 V/2.5 V Interfaces .................................................................................................................... 873 3.3 V/2.5 V, 3.3 V/1.8 V, 2.5 V/1.8 V Interfaces ............................................................................ 874 Hot Swap and Hot Plug Applications of Bus Switches ................................................................. 878 Internally Created Voltage Tolerance / Compliance ...................................................................... 879 Section 9-8: Breadboarding and Prototyping ...............................................................................881 “Deadbug” Prototyping ................................................................................................................. 882 Solder-Mount Prototyping ............................................................................................................. 884 Milled PCB Prototyping ................................................................................................................ 885 Beware of Sockets ......................................................................................................................... 886 Some Additional Prototyping Points ............................................................................................. 887 Evaluation Boards .......................................................................................................................... 887 General-Purpose Op Amp Evaluation Board from the Mid-1990s ........................................ 888 Dedicated Op Amp Evaluation Boards .................................................................................. 888 Data Converter Evaluation Boards ......................................................................................... 890 Index ...............................................................................................................................895

【大数据+spark+数据清洗】hotel_data 学习大数据清洗的数据 对应文章：https://blog.csdn.net/weixin_44018458/article/details/128980802 数据内容： 省份,城市,商圈,星级,业务部门,房间数,图片数,评分,评论数,城市平均实住间夜,酒店总订单,酒店总间夜,酒店实住订单,酒店实住间夜,酒店直销订单,酒店直销间夜,酒店直销实住订单,酒店直销实住间夜,酒店直销拒单,酒店直销拒单率,城市直销订单,城市直销拒单率,拒单率是否小于等于直销城市均值 aba_2066,马尔康嘉绒大酒店,中国,四川,阿坝,NULL,四星级/高档,OTA,85,NULL,4.143799782,108,34.06,45,75,22,44,NULL,NULL,NULL,NULL,NULL,NULL,34147,7.90%,0 aba_2069,阿坝马尔康县澜峰大酒店,中国,四川,阿坝,NULL,二星及其他,低星,115,NULL,3.977930069,129,34.06,35,72,27,59,34,71,27,59,6,17.65%,34

7-Data Recovery Suite是一款win8界面风格的多功能数据恢复软件，可以从硬盘、 内存卡、 闪存驱动器和移动电话中恢复已丢失/已删除的照片、 文件、 分区，和更多的相关文件。 软件支持： 支持的存储设备：DE硬盘，SATA硬盘，SCSI硬盘，火线硬盘，固态硬盘，USB硬盘，外置硬盘驱动器，硬件RAID，软盘驱动器，USB闪存盘，闪存卡，安全数码卡，存储卡/记忆棒，微卡，Zip驱动器， IPOD，其他存储设备 支持的文件系统：EXFAT、 NTFS5、 NTFS、 FAT32、 FAT16、 FAT12 支持的操作系统：Windows 8、 Win7、 Vista、 WinXP、 Windows Server 2008，Windows Server 2003 功能特色： 意外删除文件恢复：设计用于恢复意外删除的数据和文件。使用先进的扫描技术和目录重组算法，7-Data Recovery Suite可以帮助您恢复已删除的数据，如从回收站清空的文件和通过使用 SHIFT + DELETE 键删除的文件。 从本地和外部驱动器的恢复：可以恢复已损坏或已格式化的硬盘或未知原因而不可访问的驱动器。换句话说，只要该分区存在，你可以使用此数据恢复模块来恢复数据的分区或记忆棒、 内存卡、 闪存驱动器，不管什么情况导致外部存储设备的数据丢失等。 从丢失和被删除的分区中恢复数据：恢复分区中丢失或删除的数据。这是最常见的数据丢失的原因。此数据恢复模块可以帮助您恢复您的数据 恢复照片、 图像、 视频和音频：7-Data Recovery Suite提供独家媒体恢复选项，允许您从硬盘、 USB 驱动器、 SD 卡、 相机和其他内存卡中恢复丢失的图像、 音频和视频文件。 内存卡恢复：数码相机或移动电话所使用的内存卡，如各种内存卡类型包括: SD 卡、 MicroSD，SDHC，（紧凑式闪存） 的 CF 卡，xD 图片卡、 记忆棒和更多7-Data Recovery Suite可以有效地恢复丢失、 删除、 损坏或格式化的照片和视频文件。

SwiftUI-UDF 该软件包的描述。

Alogrithm Design Manual一书中作者强烈推荐的数据结构方面的参考书，可以当做数据结构的工具书来用，可以查到各种基本数据结构及其用法。在网上找了很久才下到的，拿来和大家分享！

南京工程学院大数据科学导论，上课PPT，期末复习笔记

RHEL 7.1安装MySQL 5.6的依赖包：perl-Data-Dumper-2.145-3.el7.x86_64.rpm ------------------------------------------------------------------------------------

智能电池规范为便携式电子设备(如笔记本电脑系统、移动电话或摄像机)中使用的电池提供了一个理想的解决方案。从用户和设备的角度来看，电池目前都有许多限制。首先，它们代表着一种不可预知的力量。通常情况下，用户事先并不知道电池即将耗尽，也不知道还剩多少操作时间。其次，由电池供电的设备不能确定电池在其当前状态下是否能够为额外的负载(如旋转硬盘)提供足够的电力。第三，电池充电器必须为特定的电池化学成分量身定制，如果用在其他不同化学成分的电池上，可能会造成损坏。

智能电池芯片的资料,主要用于笔记本电池等