Drain Current for the Saturation Region

(-15)

Because the standard SPICE Level-1 model does not include any of the short-channel phenomena, such as mobility modulation and velocity-saturation effects, the uses for this model are limited. To retain high computational efficiency and improve accuracy, the Spectre^® circuit simulator incorporates two parameters, theta and vmax, into the Level-1 model. The meanings of theta and vmax are the same as those in the Level-3 model. The modified Level-1 model is like a simplified Level-3 model. Spectre uses the modified Level-1 model if theta or vmax (or both) is specified. The drain current equations for the modified Level-1 model are shown in the following section.