Hi all,

I am using OPA2140 as my 2nd stage of my transimpendance amplifier (reference: http://e2e.ti.com/support/amplifiers/precision_amplifiers/f/14/t/158884.aspx#584443). Following the SLOA070 guide, I successfully imported the Spice Model in PSpice and changed it symbol to a triangular shape accordingly. What I notice when I was changing the symbol is that apart from the familiar OPA2140 sub-circuit, I also see a list of other sub-circuits -- FEMT_0, IDEAL_D_0, IDEAL_D_1, etc. Surely, because I did not attend to these sub-circuits, a bunch of errors was generated during simulation (as follows):

ERROR(ORPSIM-15108): Subcircuit IDEAL_D_0 used by X_U1.XU12 is undefined

ERROR(ORPSIM-15108): Subcircuit IDEAL_D_0 used by X_U1.XU8 is undefined

ERROR(ORPSIM-15108): Subcircuit FEMT_0 used by X_U1.XIn11 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR109 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR109_2 is undefined

ERROR(ORPSIM-15108): Subcircuit VNSE_0 used by X_U1.XVn11 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_0 used by X_U1.XU14 is undefined

ERROR(ORPSIM-15108): Subcircuit IDEAL_D_1 used by X_U1.XU13 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR109_3 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_1 used by X_U1.XR109_4 is undefined

ERROR(ORPSIM-15108): Subcircuit VARICAP_0 used by X_U1.XU9 is undefined

ERROR(ORPSIM-15108): Subcircuit VC_RES_0 used by X_U1.XU7 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_1 used by X_U1.XU5 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_2 used by X_U1.XU6 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_3 used by X_U1.XU3 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_3 used by X_U1.XU1 is undefined

ERROR(ORPSIM-15108): Subcircuit IDEAL_D_1 used by X_U1.XU2 is undefined

ERROR(ORPSIM-15108): Subcircuit VCCS_LIMIT_0 used by X_U1.XU26 is undefined

ERROR(ORPSIM-15108): Subcircuit VCCS_LIMIT_1 used by X_U1.XU4 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_4 used by X_U1.XVCVSPSRR is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_5 used by X_U1.XU22 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_5 used by X_U1.XU21 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_5 used by X_U1.XU20 is undefined

ERROR(ORPSIM-15108): Subcircuit VCVS_LIMIT_6 used by X_U1.XU19 is undefined

ERROR(ORPSIM-15108): Subcircuit IDEAL_D_0 used by X_U1.XU11 is undefined

ERROR(ORPSIM-15108): Subcircuit IDEAL_D_0 used by X_U1.XU10 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_1 used by X_U1.XR109_5 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR102 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR101 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR105 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_2 used by X_U1.XR104 is undefined

ERROR(ORPSIM-15108): Subcircuit RNOISE_FREE_0 used by X_U1.XR103 is undefined

Subsequently, I tried the PSpice model for OPA140, thinking it does not include those extra sub-circuits, but I was wrong. These sub-circuits seem to be parameters that I can fine tune for my simulation, however, I do not have a proper understanding what each one are. My search online and in the forum for these parameters came out nothing. Please let me know if anyone has some insight into this. Thank you in advance!

- Wayne Chu