OrCad Capture: Convergence Problem

loki3118 · Jan 9, 2014

Hello,

I'm trying to simulate the behavior of a Full Bridge Class D amplifier using EPC2014 spice models. However, when I preform a transient analysis on the circuit i get the following error:

"ERROR(ORPSIM-15138): Convergence problem in transient analysis at Time = 382.2E-18. Time step = 745.1E-21, minimum allowable step size = 1.000E-18"

I've followed the simple solutions, from http://www.intusoft.com/articles/converg.pdf, in an attempt to fix the problem but have not had any luck.

Does anyone have a recommendation on things I should try and change in-order to get the circuit to converge?

Below is my simple half-bridge amplifier with no output filter and the complete error code.

Code:

**** 01/09/14 13:43:52 ***** PSpice 16.6.0 (October 2012) ***** ID# 0 ********

 ** Profile: "SCHEMATIC1-Transient"  [ E:\Taylor\PSpice\full_bridge_real_mosfets-pspicefiles\schematic1\transient.sim ] 


 ****     CIRCUIT DESCRIPTION


******************************************************************************




** Creating circuit file "Transient.cir" 
** WARNING: THIS AUTOMATICALLY GENERATED FILE MAY BE OVERWRITTEN BY SUBSEQUENT SIMULATIONS

*Libraries: 
* Profile Libraries :
* Local Libraries :
.LIB "C:/Cadence/SPB_16.6/tools/pspice/User_Files/EPC2014/EPC2014.lib" 
* From [PSPICE NETLIST] section of C:\Users\dmaser\AppData\Roaming\SPB_Data\cdssetup\OrCAD_PSpice/16.6.0/PSpice.ini file:
.lib "nom.lib" 

*Analysis directives: 
.TRAN  0 10us 0 
.OPTIONS ADVCONV
.OPTIONS ABSTOL= 0.10n
.OPTIONS CHGTOL= 0.01n
.OPTIONS GMIN= 1.0E-9
.OPTIONS METHOD= Default
.OPTIONS GMINSTEPS= 10
.PROBE64 V(alias(*)) I(alias(*)) W(alias(*)) D(alias(*)) NOISE(alias(*)) 
.INC "..\SCHEMATIC1.net" 



**** INCLUDING SCHEMATIC1.net ****
* source FULL_BRIDGE_REAL_MOSFETS
V_V3         VDD1 0 5Vdc
R_R6         0 VDD1  1.5k TC=0,0 
R_R16         N94360 N94372  0.5 TC=0,0 
X_U1         N97231 VDD1 N94360 EPC2014
X_U2         N97257 N94360 0 EPC2014
X_U3         N97304 N94372 0 EPC2014
X_U4         N97219 VDD2 N94372 EPC2014
R_R17         LO2 N97219  2 TC=0,0 
R_R18         HO2 N97304  2 TC=0,0 
R_R19         LO2 N97257  2 TC=0,0 
R_R20         HO2 N97231  2 TC=0,0 
V_V6         VDD2 0 5Vdc
R_R21         0 VDD2  1.5k TC=0,0 
V_V7         LO2 0  
+PULSE 0 3.3 1u 10n 10n 1u 2u
V_V8         HO2 0  
+PULSE 0 3.3 0u 10n 10n 1u 2u
R_R22         HO2 0  50 TC=0,0 
R_R23         LO2 0  50 TC=0,0 

**** RESUMING Transient.cir ****
.END

**** 01/09/14 13:43:52 ***** PSpice 16.6.0 (October 2012) ***** ID# 0 ********

 ** Profile: "SCHEMATIC1-Transient"  [ E:\Taylor\PSpice\full_bridge_real_mosfets-pspicefiles\schematic1\transient.sim ] 


 ****     INITIAL TRANSIENT SOLUTION       TEMPERATURE =   27.000 DEG C


******************************************************************************



 NODE   VOLTAGE     NODE   VOLTAGE     NODE   VOLTAGE     NODE   VOLTAGE


(  HO2)    0.0000  (  LO2)    0.0000  ( VDD1)    5.0000  ( VDD2)    5.0000      

(N94360)     .2684 (N94372)     .2684 (N97219) 258.9E-09 (N97231) 258.9E-09     

(N97257) 46.94E-09 (N97304) 46.94E-09 (X_U1.gate) 336.5E-09                     

(X_U2.gate) 61.03E-09                 (X_U3.gate) 61.03E-09                     

(X_U4.gate) 336.5E-09                 (X_U1.bl_gd)    5.0000                    

(X_U1.bl_gs)     .2684                (X_U1.bl_sd)    5.0000                    

(X_U1.br_gd)    5.0000                (X_U1.br_gs)     .2684                    

(X_U1.br_sd)    5.0000                (X_U1.drain)    5.0000                    

(X_U1.tl_gd)    5.0000                (X_U1.tl_gs)     .2684                    

(X_U1.tl_sd)    5.0000                (X_U1.tr_gd)    5.0000                    

(X_U1.tr_gs)     .2684                (X_U1.tr_sd)    5.0000                    

(X_U2.bl_gd)     .2684                (X_U2.bl_gs) 2.498E-09                    

(X_U2.bl_sd)     .2684                (X_U2.br_gd)     .2684                    

(X_U2.br_gs) 2.498E-09                (X_U2.br_sd)     .2684                    

(X_U2.drain)     .2684                (X_U2.tl_gd)     .2684                    

(X_U2.tl_gs) 2.187E-09                (X_U2.tl_sd)     .2684                    

(X_U2.tr_gd)     .2684                (X_U2.tr_gs) 2.187E-09                    

(X_U2.tr_sd)     .2684                (X_U3.bl_gd)     .2684                    

(X_U3.bl_gs) 2.498E-09                (X_U3.bl_sd)     .2684                    

(X_U3.br_gd)     .2684                (X_U3.br_gs) 2.498E-09                    

(X_U3.br_sd)     .2684                (X_U3.drain)     .2684                    

(X_U3.tl_gd)     .2684                (X_U3.tl_gs) 2.187E-09                    

(X_U3.tl_sd)     .2684                (X_U3.tr_gd)     .2684                    

(X_U3.tr_gs) 2.187E-09                (X_U3.tr_sd)     .2684                    

(X_U4.bl_gd)    5.0000                (X_U4.bl_gs)     .2684                    

(X_U4.bl_sd)    5.0000                (X_U4.br_gd)    5.0000                    

(X_U4.br_gs)     .2684                (X_U4.br_sd)    5.0000                    

(X_U4.drain)    5.0000                (X_U4.tl_gd)    5.0000                    

(X_U4.tl_gs)     .2684                (X_U4.tl_sd)    5.0000                    

(X_U4.tr_gd)    5.0000                (X_U4.tr_gs)     .2684                    

(X_U4.tr_sd)    5.0000                (X_U1.source)     .2684                   

(X_U2.source) 2.498E-09               (X_U3.source) 2.498E-09                   

(X_U4.source)     .2684               




    VOLTAGE SOURCE CURRENTS
    NAME         CURRENT

    V_V3        -3.335E-03
    V_V6        -3.335E-03
    V_V7         1.529E-07
    V_V8         1.529E-07
    X_U1.V_INGS   0.000E+00
    X_U1.V_INGD   0.000E+00
    X_U1.V_INSD   0.000E+00
    X_U2.V_INGS   0.000E+00
    X_U2.V_INGD   0.000E+00
    X_U2.V_INSD   0.000E+00
    X_U3.V_INGS   0.000E+00
    X_U3.V_INGD   0.000E+00
    X_U3.V_INSD   0.000E+00
    X_U4.V_INGS   0.000E+00
    X_U4.V_INGD   0.000E+00
    X_U4.V_INSD   0.000E+00

    TOTAL POWER DISSIPATION   3.33E-02  WATTS

Reducing minimum delta to make the circuit converge.

ERROR(ORPSIM-15138): Convergence problem in transient analysis at Time =  382.2E-18.
         Time step =  745.1E-21, minimum allowable step size =  1.000E-18

  These voltages failed to converge:

    V(N97257)                 =    22.76mV  \    22.73mV
    V(X_U1.tl_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.bl_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.br_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.tr_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.tl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.bl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.br_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.tr_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.tl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U1.bl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U1.br_sd)             =   -7.533mV  \   -14.18mV
    V(X_U1.tr_sd)             =   -7.533mV  \   -14.18mV
    V(X_U2.gate)              =    29.59mV  \    29.55mV
    V(X_U2.tl_gs)             =   179.69uV  \   338.17uV
    V(X_U2.bl_gs)             =   179.69uV  \   338.17uV
    V(X_U2.br_gs)             =   179.69uV  \   338.17uV
    V(X_U2.tr_gs)             =   179.69uV  \   338.17uV
    V(X_U2.tl_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.bl_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.br_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.tr_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.tl_sd)             =   -3.882mV  \   -7.305mV
    V(X_U2.bl_sd)             =   -3.882mV  \   -7.305mV
    V(X_U2.br_sd)             =   -3.882mV  \   -7.305mV
    V(X_U2.tr_sd)             =   -3.882mV  \   -7.305mV
    V(X_U3.tl_gs)             =   179.69uV  \   338.17uV
    V(X_U3.bl_gs)             =   179.69uV  \   338.17uV
    V(X_U3.br_gs)             =   179.69uV  \   338.17uV
    V(X_U3.tr_gs)             =   179.69uV  \   338.17uV
    V(X_U3.tl_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.bl_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.br_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.tr_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.tl_sd)             =   -3.882mV  \   -7.304mV
    V(X_U3.bl_sd)             =   -3.882mV  \   -7.304mV
    V(X_U3.br_sd)             =   -3.882mV  \   -7.304mV
    V(X_U3.tr_sd)             =   -3.882mV  \   -7.304mV
    V(X_U4.tl_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.bl_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.br_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.tr_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.tl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.bl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.br_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.tr_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.tl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U4.bl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U4.br_sd)             =   -7.533mV  \   -14.18mV
    V(X_U4.tr_sd)             =   -7.533mV  \   -14.18mV



  Last node voltages tried were:

 NODE   VOLTAGE     NODE   VOLTAGE     NODE   VOLTAGE     NODE   VOLTAGE


(  HO2) 127.9E-09  (  LO2)    0.0000  ( VDD1)    5.0000  ( VDD2)    5.0000      

(N94360)    2.3868 (N94372)    2.3869 (N97219)    1.6814 (N97231)    1.6813     

(N97257)     .0228 (N97304)     .0228 (X_U1.gate)    2.1857                     

(X_U2.gate)     .0296                 (X_U3.gate)     .0296                     

(X_U4.gate)    2.1858                 (X_U1.bl_gd)    -.0075                    

(X_U1.bl_gs)    -.0032                (X_U1.bl_sd)    -.0075                    

(X_U1.br_gd)    -.0075                (X_U1.br_gs)    -.0032                    

(X_U1.br_sd)    -.0075                (X_U1.drain)    5.3788                    

(X_U1.tl_gd)    -.0075                (X_U1.tl_gs)    -.0032                    

(X_U1.tl_sd)    -.0075                (X_U1.tr_gd)    -.0075                    

(X_U1.tr_gs)    -.0032                (X_U1.tr_sd)    -.0075                    

(X_U2.bl_gd)    -.0039                (X_U2.bl_gs) 179.7E-06                    

(X_U2.bl_sd)    -.0039                (X_U2.br_gd)    -.0039                    

(X_U2.br_gs) 179.7E-06                (X_U2.br_sd)    -.0039                    

(X_U2.drain)    2.7716                (X_U2.tl_gd)    -.0039                    

(X_U2.tl_gs) 179.7E-06                (X_U2.tl_sd)    -.0039                    

(X_U2.tr_gd)    -.0039                (X_U2.tr_gs) 179.7E-06                    

(X_U2.tr_sd)    -.0039                (X_U3.bl_gd)    -.0039                    

(X_U3.bl_gs) 179.7E-06                (X_U3.bl_sd)    -.0039                    

(X_U3.br_gd)    -.0039                (X_U3.br_gs) 179.7E-06                    

(X_U3.br_sd)    -.0039                (X_U3.drain)    2.7717                    

(X_U3.tl_gd)    -.0039                (X_U3.tl_gs) 179.7E-06                    

(X_U3.tl_sd)    -.0039                (X_U3.tr_gd)    -.0039                    

(X_U3.tr_gs) 179.7E-06                (X_U3.tr_sd)    -.0039                    

(X_U4.bl_gd)    -.0075                (X_U4.bl_gs)    -.0032                    

(X_U4.bl_sd)    -.0075                (X_U4.br_gd)    -.0075                    

(X_U4.br_gs)    -.0032                (X_U4.br_sd)    -.0075                    

(X_U4.drain)    5.3788                (X_U4.tl_gd)    -.0075                    

(X_U4.tl_gs)    -.0032                (X_U4.tl_sd)    -.0075                    

(X_U4.tr_gd)    -.0075                (X_U4.tr_gs)    -.0032                    

(X_U4.tr_sd)    -.0075                (X_U1.source)    2.2585                   

(X_U2.source)    -.1283               (X_U3.source)    -.1283                   

(X_U4.source)    2.2586               


**** Interrupt ****
**** Param: RELTOL = 0.001
**** Param: ABSTOL = 1e-010
**** Param: VNTOL = 1e-006
**** Param: GMIN = 1e-009
**** Param: TSTOP = 1e-005
**** Param: TMAX = 0
**** Param: ITL1 = 150
**** Param: ITL2 = 20
**** Param: ITL4 = 10
**** Param: AutoConverge = 0
**** Param: AutoConverge.ITL1 = 1000
**** Param: AutoConverge.ITL2 = 1000
**** Param: AutoConverge.ITL4 = 1000
**** Param: AutoConverge.RELTOL = 0.05
**** Param: AutoConverge.ABSTOL = 0.001
**** Param: AutoConverge.VNTOL = 0.001
**** Param: AutoConverge.PIVTOL = 1e-010
**** Param: ADVCONV = 1
**** Param: Current_Simulation = 3
**** Param: METHOD = 0
**** Param: TRTOL = 7
**** Param: STEPGMIN = 0
**** Param: GMINSTEPS = 10
**** Param: ITL6 = 0
**** Param: NOSTEPDEP = 0
**** Param: PTRANSTEP = 0
**** Param: GMINSRC = 0
**** Param: PSEUDOTRAN = 0
**** Param: NOSTEPSRC = 0

ERROR(ORPSIM-15138): Convergence problem in transient analysis at Time =  382.2E-18.
         Time step =  745.1E-21, minimum allowable step size =  1.000E-18

  These voltages failed to converge:

    V(N97257)                 =    22.76mV  \    22.73mV
    V(X_U1.tl_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.bl_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.br_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.tr_gs)             =   -3.163mV  \   -5.954mV
    V(X_U1.tl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.bl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.br_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.tr_gd)             =   -7.533mV  \   -14.18mV
    V(X_U1.tl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U1.bl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U1.br_sd)             =   -7.533mV  \   -14.18mV
    V(X_U1.tr_sd)             =   -7.533mV  \   -14.18mV
    V(X_U2.gate)              =    29.59mV  \    29.55mV
    V(X_U2.tl_gs)             =   179.69uV  \   338.17uV
    V(X_U2.bl_gs)             =   179.69uV  \   338.17uV
    V(X_U2.br_gs)             =   179.69uV  \   338.17uV
    V(X_U2.tr_gs)             =   179.69uV  \   338.17uV
    V(X_U2.tl_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.bl_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.br_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.tr_gd)             =   -3.882mV  \   -7.305mV
    V(X_U2.tl_sd)             =   -3.882mV  \   -7.305mV
    V(X_U2.bl_sd)             =   -3.882mV  \   -7.305mV
    V(X_U2.br_sd)             =   -3.882mV  \   -7.305mV
    V(X_U2.tr_sd)             =   -3.882mV  \   -7.305mV
    V(X_U3.tl_gs)             =   179.69uV  \   338.17uV
    V(X_U3.bl_gs)             =   179.69uV  \   338.17uV
    V(X_U3.br_gs)             =   179.69uV  \   338.17uV
    V(X_U3.tr_gs)             =   179.69uV  \   338.17uV
    V(X_U3.tl_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.bl_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.br_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.tr_gd)             =   -3.882mV  \   -7.304mV
    V(X_U3.tl_sd)             =   -3.882mV  \   -7.304mV
    V(X_U3.bl_sd)             =   -3.882mV  \   -7.304mV
    V(X_U3.br_sd)             =   -3.882mV  \   -7.304mV
    V(X_U3.tr_sd)             =   -3.882mV  \   -7.304mV
    V(X_U4.tl_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.bl_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.br_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.tr_gs)             =   -3.163mV  \   -5.952mV
    V(X_U4.tl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.bl_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.br_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.tr_gd)             =   -7.533mV  \   -14.18mV
    V(X_U4.tl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U4.bl_sd)             =   -7.533mV  \   -14.18mV
    V(X_U4.br_sd)             =   -7.533mV  \   -14.18mV
    V(X_U4.tr_sd)             =   -7.533mV  \   -14.18mV



  Last node voltages tried were:

 NODE   VOLTAGE     NODE   VOLTAGE     NODE   VOLTAGE     NODE   VOLTAGE


(  HO2) 127.9E-09  (  LO2)    0.0000  ( VDD1)    5.0000  ( VDD2)    5.0000      

(N94360)    2.3868 (N94372)    2.3869 (N97219)    1.6814 (N97231)    1.6813     

(N97257)     .0228 (N97304)     .0228 (X_U1.gate)    2.1857                     

(X_U2.gate)     .0296                 (X_U3.gate)     .0296                     

(X_U4.gate)    2.1858                 (X_U1.bl_gd)    -.0075                    

(X_U1.bl_gs)    -.0032                (X_U1.bl_sd)    -.0075                    

(X_U1.br_gd)    -.0075                (X_U1.br_gs)    -.0032                    

(X_U1.br_sd)    -.0075                (X_U1.drain)    5.3788                    

(X_U1.tl_gd)    -.0075                (X_U1.tl_gs)    -.0032                    

(X_U1.tl_sd)    -.0075                (X_U1.tr_gd)    -.0075                    

(X_U1.tr_gs)    -.0032                (X_U1.tr_sd)    -.0075                    

(X_U2.bl_gd)    -.0039                (X_U2.bl_gs) 179.7E-06                    

(X_U2.bl_sd)    -.0039                (X_U2.br_gd)    -.0039                    

(X_U2.br_gs) 179.7E-06                (X_U2.br_sd)    -.0039                    

(X_U2.drain)    2.7716                (X_U2.tl_gd)    -.0039                    

(X_U2.tl_gs) 179.7E-06                (X_U2.tl_sd)    -.0039                    

(X_U2.tr_gd)    -.0039                (X_U2.tr_gs) 179.7E-06                    

(X_U2.tr_sd)    -.0039                (X_U3.bl_gd)    -.0039                    

(X_U3.bl_gs) 179.7E-06                (X_U3.bl_sd)    -.0039                    

(X_U3.br_gd)    -.0039                (X_U3.br_gs) 179.7E-06                    

(X_U3.br_sd)    -.0039                (X_U3.drain)    2.7717                    

(X_U3.tl_gd)    -.0039                (X_U3.tl_gs) 179.7E-06                    

(X_U3.tl_sd)    -.0039                (X_U3.tr_gd)    -.0039                    

(X_U3.tr_gs) 179.7E-06                (X_U3.tr_sd)    -.0039                    

(X_U4.bl_gd)    -.0075                (X_U4.bl_gs)    -.0032                    

(X_U4.bl_sd)    -.0075                (X_U4.br_gd)    -.0075                    

(X_U4.br_gs)    -.0032                (X_U4.br_sd)    -.0075                    

(X_U4.drain)    5.3788                (X_U4.tl_gd)    -.0075                    

(X_U4.tl_gs)    -.0032                (X_U4.tl_sd)    -.0075                    

(X_U4.tr_gd)    -.0075                (X_U4.tr_gs)    -.0032                    

(X_U4.tr_sd)    -.0075                (X_U1.source)    2.2585                   

(X_U2.source)    -.1283               (X_U3.source)    -.1283                   

(X_U4.source)    2.2586               


**** Interrupt ****

FvM · Jan 9, 2014

There may be additional reasons for convergence problems, but the gate driver circuit is definitely wrong. The high side gate voltages must be applied between gate and source of the high side transistors, not between gate and ground.

andre_luis · Jan 9, 2014

I'm not sure if this could contribute to generate the error shown, but could just as trying, use templates to the device from other libraries:

This App note employs above model and provide some tips:
https://www.digikey.tw/Web Export/S...7/PDF/EPC_Circuit_Simulations_Using_SPICE.pdf

+++

atripathi · Jan 13, 2014

U1 and U4 need floating gate drive. One simple way to implement that in simulation is to use 4 voltage sources instead if two, and connect these to appropriate MOSFETs so that they refer to respective source terminals. This is pretty simple circuit and I am sure it would work with above change.

OrCad Capture: Convergence Problem

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