ASCII (hex 2D) − minus/dash/hyphen character. Suffix replacing decimal point. See option setting at LTspice -> Tools -> Control Panel -> SPICE -> Accept 3K4 as 3.4K. LTspice does not support the following features: LTspice does not support scale factors of "atto" 10−18, "peta" 1015, or "exa" 1018. HSPICE supports 'a' for "atto" 10−18, which must be replaced with 'e-18' to be compatible with LTspice and other SPICE software. HSPICE supports 'X' as a synonym for "meg" 106, which must be replaced with 'e6' or 'MEG'to be compatible with LTspice and other SPICE software. Node name conventions In LTspice, a node/net (connection point) on the schematic can be labeled by using the Label Net tool button or F4 key. The "Label Net" wizard has three choices for a label, two predefined graphical symbols (GND, COM), or a user-defined node/net name. The two graphical symbols represent: GND - The ground symbol assigns a node with a special global net name of "0". COM - The COM symbol assigns a node with a net name of "COM", which doesn't have any special significance. Historically, SPICE and older version of LTspice software only supported printable ASCII characters for node/net names, then LTspice XVII added support for Unicode characters. A user-defined name supports two optional features that can be prepended to the text name: _ - An underscore causes an overbar to be placed above the entire name, which commonly means an active low signal. For example, "_RESET" is shown on the schematic as "". $G_ - This means a node is global, no matter where the name occurs in the circuit hierarchy. For example, "$G_ENABLE" / "$G_ERROR". The ground symbol is treated in a similar way, but it does not have "$G_" prepended to it. When a node/net name is placed on a schematic, it will have one of five different visual representations. Two are automatically determined, while three others are chosen by the "Port Type" field in the "Label Net" wizard. None - Bare text. This is the default. Global - "Rectangle" around the text. This is automatically shown for a global net name that starts with "$G_". Input - "Rectangle with triangle end" around the text. This is chosen by the "Port Type" field in the "Label Net" wizard. Output - "Rectangle with triangle on other end" around the text. This is chosen by the "Port Type" field in the "Label