| Component | Syntax |
| Special Functions | Axx n1 n2 n3 n4 n5 n6 n7 n8 + <model> [extra parameters] |
| Arbitrary Behavioral Source | Bxx n+ n- <V=... or I=...> |
| Capacitor | Cxx n+ n- <capacitance> + [ic=<val.>] [Rser=<val.>] + [Lser=<val.>] [Rpar=<val.>] + [Cpar=<val.>] [m=<val.>] |
| Diode | Dxx A K <model> [area] |
| Voltage Dependent Voltage | Exx n+ n- nc+ nc- <gain> |
| Current Dependent Current | Fxx n+ n- <Vnam> <gain> |
| Voltage Dependent Current | Gxx n+ n- nc+ nc- <transcond.> |
| Current Dependent Voltage | Hxx n+ n- <Vnam> <transres.> |
| Independent Current source | Ixx n+ n- <current> |
| JFET Transistor | Jxx D G S <model> [area] [off] +[IC=<Vds,Vgs>] [temp=<T>] |
| Mutual Inductance | Kxx L1 L2 L3... <coeff.> |
| Inductance | Lxx n+ n- <inductance> + [ic=<val.>] [Rser=<val.>] + [Rpar=<val.>] + [Cpar=<val.>] [m=<val.>] |
| MOSFET Transistor | Mxx D G S B <model> [L=<len>] + [W=<width>] [AD=<area>] + [AS=<area>] [PD=<perim>] + [PS=<perim>] [NRD=<value>] + [NRS=<value>] [off] + [IC=<Vds, Vgs, Vbs> + [temp=<T>] |
| Lossy Transmission Line | Oxx L+ L- R+ R- <model> |
| Bipolar Transistor | Qxx C B E [S] <model> [area] + [off] [IC=Vbe,Vce][temp=<T>] |
| Resistor | Rxx n1 n2 <value> |
| Voltage Controlled Switch | Sxx n1 n2 nc+ nc- <model> + [on,off] |
| Lossless Transmission Line | Txx L+ L- R+ R- ZO=<value> + TD=<value> |
| Uniform RC-line | Uxx n1 n2 ncommon <model> + L=<len> [N=<lumps>] |
| Independent Voltage Source | Vxx n+ n- <voltage> |
| Current Controlled Switch | Wxx n1 n2 <Vnam> <model> + [on,off] |
| Subcircuit | Xxx n1 n2 n3... <subckt name> |
| MESFET Transistor | Zxx D G S model [area] [off] + [IC=<Vds,Vgs>] |
An invaluable reference that complements the LTspice help documentation is the 2nd Edition of Semiconductor Device Modeling with SPICE by Giuseppe Massobrio and Paolo Antognetti, McGraw Hill, 1993 and later reprints. That book documents the semiconductor device equations and extensions that have been used in various commercial SPICE programs including those used in this one. For BSIM 3 and 4 devices, see the relevant documentation available from the UC Berkeley CAD group.