Table of Contents Introduction 4 Preface ............................................................................................................ 4 Hardware Requirements.................................................................................. 5 Software Installation ........................................................................................ 6 License Agreement/Disclaimer........................................................................ 6 Mode of Operation 8 Overview.......................................................................................................... 8 Example Circuits.............................................................................................. 8 General Purpose Schematic Driven SPICE .................................................... 9 Externally Generated Netlists........................................................................ 10 Efficiency Report ........................................................................................... 11 Command Line Switches............................................................................... 13 Schematic Capture 14 Basic Schematic Editing................................................................................ 14 Label a node name........................................................................................ 17 Schematic Colors .......................................................................................... 19 Placing New Components ............................................................................. 20 Programming Keyboard Shortcuts ................................................................ 20 PCB Netlist Extraction ................................................................................... 21 Editing Components ...................................................................................... 22 Edit a Visible Attribute............................................................................. 22 Specialized Component Editors.............................................................. 23 General Attribute Editor .......................................................................... 24 Creating New Symbols .................................................................................. 26 Symbol Editing Overview ........................................................................ 26 Drawing the body .................................................................................... 27 Adding the Pins....................................................................................... 27 Adding Attributes..................................................................................... 28 Attribute Visibility..................................................................................... 30 Automatic Symbol Generation ................................................................ 31 Hierarchy ....................................................................................................... 32 Hierarchy Overview................................................................................. 32 Rules of Hierarchy................................................................................... 32 Navigating the Hierarchy......................................................................... 33 Waveform Viewer 35 Waveform Viewer Overview .......................................................................... 35 Data Trace Selection ..................................................................................... 35 Zooming......................................................................................................... 40 Waveform Arithmetic ..................................................................................... 40 User-Defined Functions................................................................................. 47 Axis Control ................................................................................................... 48 Plot Panes .....................................................................................................48 Color Control.................................................................................................. 49 Attached Cursors........................................................................................... 50 Save Plot Configurations............................................................................... 54 Fast Access File Format................................................................................ 55 1 LTspice® 57 Introduction.................................................................................................... 58 Circuit Description................................................................................... 58 General Structure and Conventions........................................................ 59 Circuit Element Quick Reference............................................................ 62 Dot Commands.............................................................................................. 63 C. Simulator Directives -- Dot Commands............................................. 63 .AC -- Perform an Small Signal AC Analysis Linearized About the DC Operating Point. ................................................................................................................ 64 .BACKANNO -- Annotate the Subcircuit Pin Names to the Port Currents65 .DC -- Perform a DC Source Sweep Analysis ........................................ 65 .END -- End of Netlist.............................................................................. 66 .ENDS -- End of Subcircuit Definition ..................................................... 66 .FOUR -- Compute a Fourier Component after a .TRAN Analysis ......... 66 .FUNC -- User Defined Functions ........................................................... 67 .FERRET -- Download a File Given the URL.......................................... 68 .IC -- Set Initial Conditions ...................................................................... 68 .INCLUDE -- Include Another File........................................................... 69 .LIB -- Include a Library........................................................................... 70 .LOADBIAS -- Load a Previously Solved DC Solution............................ 73 .MEASURE -- Evaluate User-Defined Electrical Quantities.................... 73 .MODEL -- Define a SPICE Model.......................................................... 77 .NET -- Compute Network Parameters in a .AC Analysis...................... 78 .NODESET -- Supply Hints for Initial DC Solution .................................. 79 .NOISE -- Perform a Noise Analysis...................................................... 80 .OP -- Find the DC Operating Point ....................................................... 81 .OPTIONS -- Set Simulator Options ....................................................... 81 .PARAM -- User-Defined Parameters.................................................... 85 .SAVE -- Limit the Quantity of Saved Data. ............................................ 90 .SAVEBIAS -- Save Operating Point to Disk .......................................... 90 .STEP -- Parameter Sweeps................................................................... 91 .SUBCKT -- Define a Subcircuit.............................................................. 92 .TEMP -- Temperature Sweeps .............................................................. 93 .TF -- Find the DC Small Signal Transfer Function................................. 94 .TRAN -- Perform a Nonlinear Transient Analysis .................................. 94 .WAVE -- Write Selected Nodes to a .Wav File. ..................................... 95 Transient Analysis Options............................................................................ 96 .TRAN Modifiers...................................................................................... 96 UIC .......................................................................................................... 96 startup ..................................................................................................... 96 steady...................................................................................................... 97 nodiscard................................................................................................. 97 step ......................................................................................................... 98 Circuit Elements ............................................................................................ 98 A. Special Functions. ............................................................................. 98 B. Arbitrary behavioral voltage or current sources............................... 101 C. Capacitor ......................................................................................... 107 D. Diode ............................................................................................... 110 E. Voltage Dependent Voltage Source ................................................ 113 F. Current Dependent Current Source................................................. 115 G. Voltage Dependent Current Source................................................ 116 H. Current Dependent Voltage Source ................................................ 117 I. Current Source.................................................................................. 118 J.