38kHz multivibrator.

Hi, I'm trying to simulate a 38kHz signal to use an IR transmitter signal on Pspice with no luck. I have tried to use a 555 timer but now trying to resort back to just implementing the multivibrator. Would anyone be able to help determine what my issues are?

I have attached my circuit and below is the error message I get from PSpice.


**** 03/14/21 23:01:15 ******* PSpice 17.4.0 (Nov 2018) ******* ID# 0 ********

** Profile: "SCHEMATIC1-test" [ C:\Users\Mark\Desktop\EE318pro2\circuit2-pspicefiles\schematic1\test.sim ]


**** CIRCUIT DESCRIPTION


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




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

*Libraries:
* Profile Libraries :
* Local Libraries :
* From [PSPICE NETLIST] section of C:\SPB_DATA\cdssetup\OrCAD_PSpice\17.4.0\PSpice.ini file:
.lib "nom.lib"

*Analysis directives:
.TRAN 0 200u 0
.OPTIONS ADVCONV
.PROBE64 V(alias(*)) I(alias(*)) W(alias(*)) D(alias(*)) NOISE(alias(*))
.INC "..\SCHEMATIC1.net"



**** INCLUDING SCHEMATIC1.net ****
* source CIRCUIT2
C_C8 0 N11131 100p TC=0,0
R_R13 0 N11279 1k TC=0,0
R_R11 N11171 VCC 1k TC=0,0
X_U4 0 N11131 N11279 VCC N11269 N11131 N11171 VCC 555C
R_R12 N11131 N11171 191k TC=0,0
C_C7 0 N11269 0.01u TC=0,0
V_V3 VCC 0 5v
R_R15 N14329 VCC 1k TC=0,0
R_R16 N14369 VCC 1.9k TC=0,0
R_R17 N14385 VCC 1.9k TC=0,0
R_R18 N14317 VCC 1k TC=0,0
C_C9 N14385 N14329 0.01u TC=0,0
C_C10 N14317 N14369 0.01u TC=0,0
Q_Q1 N14317 N14385 N14487 Q2PC4081Q/PLP
Q_Q2 N14329 N14369 N14487 Q2PC4081Q/PLP
R_R19 N14487 N14317 1k TC=0,0
R_R20 N14329 N14487 1k TC=0,0
R_R22 N16054 VCC 91k TC=0,0
R_R23 N16058 VCC 91k TC=0,0
R_R24 N16062 VCC 2.2k TC=0,0
Q_Q4 N16062 N16058 0 Q2PC4081Q/PLP
R_R25 N16050 0 1k TC=0,0
Q_Q3 N16050 N16054 0 Q2PC4081Q/PLP
R_R21 N16050 VCC 2.2k TC=0,0
C_C12 N16062 N16054 220n TC=0,0
R_R26 0 N16062 1k TC=0,0
C_C11 N16058 N16050 220n TC=0,0
R_R27 0 N14487 1G TC=0,0

**** RESUMING test.cir ****
.END

**** 03/14/21 23:01:15 ******* PSpice 17.4.0 (Nov 2018) ******* ID# 0 ********

** Profile: "SCHEMATIC1-test" [ C:\Users\Mark\Desktop\EE318pro2\circuit2-pspicefiles\schematic1\test.sim ]


**** Diode MODEL PARAMETERS


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




X_U4.DIODE
IS 10.000000E-15
RS .01


**** 03/14/21 23:01:15 ******* PSpice 17.4.0 (Nov 2018) ******* ID# 0 ********

** Profile: "SCHEMATIC1-test" [ C:\Users\Mark\Desktop\EE318pro2\circuit2-pspicefiles\schematic1\test.sim ]


**** BJT MODEL PARAMETERS


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




Q2PC4081Q/PLP
NPN
LEVEL 1
IS 15.330000E-15
BF 178.7
NF 1.002
VAF 69.7
IKF .1216
ISE 793.200000E-18
NE 1.436
BR 8.628
NR 1.004
VAR 44.7
IKR .1121
ISC 83.050000E-15
NC 1.207
ISS 0
RB 1
RBM 1
IRB 1.000000E-06
RE .361
RC 1.382
CJE 14.570000E-12
VJE .65
MJE .3393
CJC 3.511000E-12
VJC .4485
MJC .3646
XCJC .6193
CJS 0
VJS .75
MJS .333
FC .9256
TF 527.500000E-12
XTF 96.78
VTF 2.012
ITF .4793
TR 0
KF 0
AF 1
CN 2.42
D .87


**** 03/14/21 23:01:15 ******* PSpice 17.4.0 (Nov 2018) ******* ID# 0 ********

** Profile: "SCHEMATIC1-test" [ C:\Users\Mark\Desktop\EE318pro2\circuit2-pspicefiles\schematic1\test.sim ]


**** Junction FET MODEL PARAMETERS


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




X_U4.JNEMOD
NJF
VTO -2.5
BETA 5.120000E-06


**** 03/14/21 23:01:15 ******* PSpice 17.4.0 (Nov 2018) ******* ID# 0 ********

** Profile: "SCHEMATIC1-test" [ C:\Users\Mark\Desktop\EE318pro2\circuit2-pspicefiles\schematic1\test.sim ]


**** MOSFET MODEL PARAMETERS


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




X_U4.PCHAN555 X_U4.NCHAN555
PMOS NMOS
LEVEL 1 1
L 100.000000E-06 100.000000E-06
W 100.000000E-06 100.000000E-06
VTO -.2 .2
KP 20.000000E-06 20.000000E-06
GAMMA 0 0
PHI .6 .6
LAMBDA 0 0
IS 10.000000E-15 10.000000E-15
JS 0 0
PB .8 .8
PBSW .8 .8
CJ 0 0
CJSW 0 0
CGSO 1.000000E-12 1.000000E-12
CGDO 1.000000E-12 1.000000E-12
CGBO 1.000000E-12 1.000000E-12
TOX 0 0
XJ 0 0
UCRIT 10.000000E+03 10.000000E+03
DIOMOD 1 1
VFB 0 0
LETA 0 0
WETA 0 0
U0 0 0
TEMP 0 0
VDD 5 5
XPART 0 0


X_U4.PCHAN555_OUT
PMOS
LEVEL 1
L 100.000000E-06
W 100.000000E-06
VTO -.2
KP 20.000000E-06
GAMMA 0
PHI .6
LAMBDA 0
IS 10.000000E-15
JS 0
PB .8
PBSW .8
CBD 200.000000E-12
CJ 0
CJSW 0
CGSO 1.000000E-12
CGDO 1.000000E-12
CGBO 1.000000E-12
TOX 0
XJ 0
UCRIT 10.000000E+03
DIOMOD 1
VFB 0
LETA 0
WETA 0
U0 0
TEMP 0
VDD 5
XPART 0


Starting pseudo-transient algorithm.

ERROR -- Convergence problem in transient bias point calculation


Last node voltages tried were:

NODE VOLTAGE NODE VOLTAGE NODE VOLTAGE NODE VOLTAGE


( VCC) 5.0000 (N11131) 3.2166 (N11171) 4.9907 (N11269) 3.3333

(N11279) 4.7109 (N14317) 5.0000 (N14329) 5.0000 (N14369) 5.0000

(N14385) 5.0000 (N14487) 5.0000 (N16050) 1.5625 (N16054) .0328

(N16058) .6699 (N16062) .0763 (X_U4.1) 431.7E-12 (X_U4.2) 1.6667

(X_U4.3)-15.50E+03 (X_U4.4) 4.2000 (X_U4.5) -.6665 (X_U4.6)-1167.0000

(X_U4.7) 4.2000 (X_U4.8) -.5995 (X_U4.9) 880.4E-06 (X_U4.10) 5.0000

(X_U4.11) .2891 (X_U4.12) 5.0000

(X_U4.13) 431.7E-12 (X_U4.14) 1.486E-09

(X_U4.15) 5.0000 (X_U4.16) 5.0000

(X_U4.17) 89.17E-12 (X_U4.18) 416.0E-12

(X_U4.19) 207.8E-12 (X_U4.20) 5.0000

(X_U4.21) .2005 (X_U4.22) 4.7957

(X_U4.23) .1336 (X_U4.24) 5.0000

(X_U4.25) 104.5E-12 (X_U4.VDD) 5.0000


These voltages failed to converge:

V(N11131) = 5.000V \ 3.217V
V(N11279) = 3.182V \ 4.711V
V(N11171) = 5.000V \ 4.991V
V(N16054) = 5.000V \ 32.77mV
V(N16062) = 75.35mV \ 76.26mV
V(X_U4.3) = -33.33KV \ -15.50KV
V(X_U4.23) = 103.77mV \ 133.55mV
V(X_U4.5) = -696.23mV \ -666.45mV
V(X_U4.6) = 16.67KV \ -1.167KV
V(X_U4.21) = 595.56mV \ 200.45mV
V(X_U4.8) = -204.44mV \ -599.55mV
V(X_U4.9) = 280.47mV \ 880.38uV
V(X_U4.11) = 1.818V \ 289.12mV
V(X_U4.20) = 4.822V \ 5.000V
V(X_U4.22) = 4.757V \ 4.796V

These supply currents failed to converge:

I(X_U4.E_EMIR) = -4.586mA \ -4.751mA
I(X_U4.E_EVAL) = 0A \ -10.34pA
I(X_U4.E_U6_E1CMP) = 3.333mA \ 1.550mA
I(X_U4.E_U7_E1CMP) = -1.667mA \ 116.72uA
I(V_V3) = -3.918mA \ -3.981mA
I(X_U4.V_U6_V2) = -3.333mA \ -1.550mA
I(X_U4.V_U7_V2) = 1.667mA \ -116.74uA

These devices failed to converge:
X_U4.D_U6_D1CLMP X_U4.D_U7_D1CLMP X_U4.M_U2_U1_M4 X_U4.M_U2_U1_M6
X_U4.M_U2_U1_M8 X_U4.M_U2_U1_M1 X_U4.M_U2_U1_M2 X_U4.M_U2_U1_M5
X_U4.M_U2_U2_M6 X_U4.M_U2_U2_M1 X_U4.M_U2_U2_M2 X_U4.M_U2_U2_M7
X_U4.M_U2_U3_M1 X_U4.M_U2_U3_M3 X_U4.M_U2_U4_M3 X_U4.M_U2_U4_M4
X_U4.M_U2_U5_M2 X_U4.M_U2_U5_M3 X_U4.M_U2_U5_M4 X_U4.M_U2_U6_M3
X_U4.M_U2_U7_M2 Q_Q3

ERROR(ORPSIM-15659): Discontinuing simulation due to convergence problem

**** Interrupt ****

Any help appreciated.

Regards,

Mark

What is the purpose of R19 and R20?

ak

Which IR sensor are you using? A few styles need a rest from the 38kHz IR illumination after a second or two.

I used a Arduino Nano for this. You can setup the hardware so it produces a 38kHz signal on pin 11 by doing,
You can then gate this on/off by setting the pin to Output/Input.

This gets rid of the problem of the AGC (Automatic Gain Control) requiring the signal to not be permanently on.

I know this is not what you asked but I've put it here in case someone comes across this thread sometime in the future.

Mike.

Convergence errors are common in Spice simulations.

You could try skipping the initial conditions calculation (.uic Spice command).

Another option is changing from the Trapezoidal integration method to Gear.
Not sure where you do that in PSpice but it should be somewhere in the Spice simulation options..

Pommie said:

I used a Arduino Nano for this. You can setup the hardware so it produces a 38kHz signal on pin 11 by doing,

Code:

  TCCR2A = _BV (COM2A0) | _BV(WGM21);  // CTC, toggle OC2A on Compare Match
  TCCR2B = _BV (CS20);   // No prescaler
  OCR2A =  207;          // compare A register value (210 * clock speed)

You can then gate this on/off by setting the pin to Output/Input.

This gets rid of the problem of the AGC (Automatic Gain Control) requiring the signal to not be permanently on.

I know this is not what you asked but I've put it here in case someone comes across this thread sometime in the future.

Click to expand...

Yes, most people don't realise you can't have a continuous carrier - so well worth mentioning.