Cadence IC618中有关scale、scalem、scalefactor的差异描述

  The multiplication factor (m) puts m devices in parallel. m is an instance parameter and need not be an integer. All devices have the multiplication factor capability.
  If you specify m in an instance statement, all currents and capacitances of that device are multiplied by m, and all resistances are divided by m. The multiplication factor, however, does not affect short-channel or narrow-gate effects in MOSFETs. For example, the following two statements might not give you the same simulation results:
m1 d g s b my_model w=10u l=1u m=10 
m1 d g s b my_model w=100u l=1u m=1
  You can also specify the multiplication factor on subcircuits. If a multiplication factor is specified in a subcircuit, it applies to all elements in that subcircuit. For example, if the multiplication factor of the subcircuit is 2 and the multiplication factor of an element in the subcircuit is 3, the effective multiplication factor for that element is 6.
  Some devices—such as BJT, JFET, and diode—have an area factor parameter (area). The area parameter has identical effect on devices as the multiplication factor.
  Scaling Factors (scale and scalem)
  scale and scalem are options that set the scaling factors for instance and model parameters, respectively. You can specify the scaling factors in the .options statement. The following devices are affected by scale or scalem:
  Capacitors
  Diodes
  Resistors
  Physical resistors (phy_res)
  All levels of MOSFET models
  These scaling factors affect capacitors, resistors, and physical resistors with specified device length (l) or width (w). scale and scalem are global options and apply to all instance and model statements for the preceding list of devices.
  Parameters are scaled according to the following rules:
  Model (instance) parameters containing units of m (meters) are multiplied by scalem (scale).
  Model (instance) parameters containing units of mn are multiplied by scalemn (scalen), where n can be a positive integer or a positive real number.
  Model (instance) parameters containing units of 1/m are divided by scalem (scale).
  Model (instance) parameters containing units of 1/mn are divided by scalemn (scalen),where n can be a positive integer or a positive real number.
  Parameters that use the units cm (1/cm, cm2, ...) and μm (1/μm, μm2, ...) are not scaled. For example, vmax, which contains the unit m/sec, is scaled by scalem, but ucrit, which has the unit V/cm, is not scaled. Similarly, nsub, which has the unit 1/cm3, is not scaled by scalem.Parameters with other units are not scaled.

GPT翻译：

    乘法因子（m）将m个设备并联。m是一个实例参数，不需要是整数。所有设备都具有乘法因子的功能。

    如果在实例语句中指定了m，那么该设备的所有电流和电容都将乘以m，而所有电阻将被m除以。然而，乘法因子不影响MOSFET的短通道或窄栅效应。例如，以下两个语句可能不会给出相同的仿真结果：

    m1 d g s b my_model w=10u l=1u m=10

    m1 d g s b my_model w=100u l=1u m=1

    您还可以在子电路中指定乘法因子。如果在子电路中指定了乘法因子，它将适用于该子电路中的所有元素。例如，如果子电路的乘法因子为2，而子电路中的一个元素的乘法因子为3，则该元素的有效乘法因子为6。 一些器件（如BJT、JFET和二极管）具有面积因子参数（area）。面积参数对器件具有与乘法因子相同的影响。

    比例因子（scale和scalem）

    scale和scalem是设置实例和模型参数的比例因子的选项。您可以在.options语句中指定比例因子。以下设备受到scale或scalem的影响：

    电容器

    二极管

    电阻器

    物理电阻器（phy_res）

    所有层次的MOSFET模型

    这些比例因子影响具有指定设备长度（l）或宽度（w）的电容器、电阻器和物理电阻器。scale和scalem是全局选项，适用于前面列表中的所有实例和模型语句。

参数按照以下规则进行缩放：

    包含单位m（米）的模型（实例）参数将乘以scalem（scale）。

    包含单位mn的模型（实例）参数将乘以scalemn（scalen），其中n可以是正整数或正实数。

    包含单位1 / m的模型（实例）参数将除以scalem（scale）。

    包含单位1 / mn的模型（实例）参数将除以scalemn（scalen），其中n可以是正整数或正实数。 

    使用单位cm（1 / cm，cm2等）和μm（1 / μm，μm2等）的参数不会缩放。例如，包含单位m / sec的vmax将通过scalem进行缩放，但具有单位V / cm的ucrit不会进行缩放。类似地，具有单位1 / cm3的nsub不会通过scalem进行缩放。 具有其他单位的参数不会进行缩放。