I think you mean OPA549: http://www.ti.com/product/opa549?keyMatch=opa549&tisearch=Search-EN-Everything * You need to set the resistor value for ILIM. I have just found that there is a problem with running the OPA549 model in current limit in EasyEDA. I am trying to find out what the problem is but it may take me a while. In the meanwhile, you can run the TI model out-of-the-box in LTspice (but you will have to create a symbol for it in LTspice). You can then import the LTspice .asc schematic straight back into EasyEDA to finish off a schematic ready for passing into PCB design.

Here's another option. You can run the netlist for an EasyEDA simulation of the OPA549 directly in LTspice. Open a new LTspice schematic, press the `S` key and then copy the netlist below and paste it into the dialogue box. Click on `OK`. Then click on the running man on the top toolbar and then, in the plot window that opens, right-click then click on `Add Trace`. Find and click on V(out) to look at the output voltage etc. I have added a parameter to adjust ILIM. :) * OPA549 test jig .tran 20u .param ILIM = 8 XU1 OUT OUT OUT IN V3_2 GND V3_2 ILIM XU1_9 D2_C D2_C OPA549 VXA1 OUT R1_2 0v V3 GND V3_2 0 V2 D2_C GND 15 V1 IN GND PULSE(0 12 0 100n 100n 4.9u 10u) AC 1 0 R2 GND ILIM {75k/ILIM-7.5k} R1 GND R1_2 1 D2 OUT D2_C 1N4001 D1 GND OUT 1N4001 ***************************************************************************** * From: * http://www.ti.com/lit/zip/sbom089 * Edited VSM and VSM2 for ngspice compatibility * signality.co.uk 161217 * ***************************************************************************** * OPA549 ***************************************************************************** * (C) Copyright 2011 Texas Instruments Incorporated. All rights reserved. ***************************************************************************** ** This model is designed as an aid for customers of Texas Instruments. ** TI and its licensors and suppliers make no warranties, either expressed ** or implied, with respect to this model, including the warranties of ** merchantability or fitness for a particular purpose. The model is ** provided solely on an "as is" basis. The entire risk as to its quality ** and performance is with the customer. ***************************************************************************** * * This model is subject to change without notice. Texas Instruments * Incorporated is not responsible for updating this model. * ***************************************************************************** * ** Released by: Analog eLab Design Center, Texas Instruments Inc. * Part: OPA549 * Date: 22JUL2011 * Model Type: ALL IN ONE * Simulator: PSPICE * Simulator Version: 16.0.0.p001 * EVM Order Number: N/A * EVM Users Guide: N/A * Datasheet: SBOS093E ? MARCH 1999 ? REVISED OCTOBER 2005 * * Model Version: 1.0 * ***************************************************************************** * * Updates: * * Version 1.0 : * Release to Web * ***************************************************************************** * CONNECTIONS: VOUT * | VOUT * | | INVERTING INPUT * | | | NON-INVERTING INPUT * | | | | NEGATIVE POWER SUPPLY * | | | | | REF VOLTAGE FOR CONTROL PINS (ES AND ILIM) * | | | | | | NEGATIVE POWER SUPPLY * | | | | | | | CURRENT LIMIT ADJUST * | | | | | | | | ENABLE/STATUS * | | | | | | | | | POSITIVE POWER SUPPLY * | | | | | | | | | | POSITIVE POWER SUPPLY * | | | | | | | | | | | .SUBCKT OPA549 OUT OUT2 - + V- REF V-2 LIM ES V+ V+2 Q2 N18 N16 N14 PSUB R3 N13 N14 8.4K Q1 N13 N12 N61 LAT5 R15 N40 VMINUS .168 Q9 VPLUS N34 N35 NMIN 2382 Q4 N25 N26 VMINUS NMAX 2 HCCVSP N47 N36 V475 -2650 HCCVSN N42 VMINUS V475 -2650 GNEGDRV VPLUS N37 N31 N36 -.00025 R4 N13 N15 8.4K GAINBLK N26 VMINUS N18 N19 .00175 R8 N19 VMINUS 1K R6 N17 + 1K R5 - N16 1K R7 N18 VMINUS 1K C2 N37 N36 11PF C1 N26 N25 31PF Q3 N19 N17 N15 PSUB Q7 VPLUS N37 N38 NMIN 128 R17 N38 VMINUS 180 D6 N32 N31 DIODE 18 D3 N27 N26 DIODE 1 D5 N27 N37 DIODE 10 D2 N23 N22 DIODE 6 D1 N60 N12 DIODE 6 VCLMP N27 VMINUS DC 1.1 VDUM N20 VMINUS DC 0 R9 N21 N20 35K C3 N21 N1N677 15PF FICOMP N37 VMINUS VDUM 1 D4 N29 N28 DIODE 1 R13 N28 VMINUS 750 Q6 N31 N29 N30 NMIN 2 R14 N30 VMINUS 300 R18 N39 N38 18 DCLAMP N37 N36 DIODE 1 R12 N1N677 N33 80 R31 N32 N34 1.9 V475 N43 Ref DC 4.75 GCLPGAIN VPLUS N51 N35 N47 .00015 Q11 N25 N51 N36 NMIN 1 C5 N51 N25 20PF D7 N48 N51 DIODE 1 VDP N48 N36 DC .65 R21 Lim N43 7500 D8 N49 N41 DIODE 1 Q12 N37 N41 VMINUS NMIN 1 GCLNGAIN VPLUS N41 N40 N42 .00015 V1I459 N49 VMINUS DC .65 C6 N41 N37 20PF DZ1 N31 N1N384 ZEN VCM VPLUS N59 DC 1.4 D9 N45 N46 DIODE 1 D10 N45 ES DIODE 1 IBES VPLUS N45 60UA R22 ES Ref 250K VBES N46 Ref DC 3.6 R16 N32 N36 500 R0 N35 N36 .168 VTHES N44 Ref DC 2.0 DP2 VMINUS - DIODE 1 DP1 - VPLUS DIODE 1 DP4 VMINUS + DIODE 1 DP3 + VPLUS DIODE 1 DP5 Ref VPLUS DIODE 10 DP6 VMINUS Ref DIODE 50 DP8 VMINUS Lim DIODE 1 DP7 Lim VPLUS DIODE 1 DP9 ES VPLUS DIODE 1 DP10 VMINUS ES DIODE 1 *SVCS1 N36 OUTPUT N45 N44 VSM RSVCS1 N36 OUTPUT R='(5e5-0.1)*0.5*(tanh((0.5-V(N45,N44))*10)+1)+0.1' *SVCS2 N32 N31 N45 N44 VSM2 RSVCS2 N32 N31 R='(1e7-1500)*0.5*(tanh((0.5-V(N45,N44))*10)+1)+1500' CS2 VMINUS - 3PF CS1 VMINUS + 3PF CS3 - + 2.5PF Q5 N25 N22 N24 LAT5 Q20 VPLUS N1N667 N1N677 NMIN 8 R11 N1N677 N32 2K R1 VPLUS N24 300 R30 N25 N1N667 2K D20 N36 N1N384 DIODE 18 RDUMMY1 V+ VPLUS 1E-4 RDUMMY2 V+2 VPLUS 1E-4 RDUMMY3 VMINUS V- 1E-4 RDUMMY5 Out OUTPUT 1E-4 RDUMMY6 Out2 OUTPUT 1E-4 RDUMMY4 VMINUS V-2 1E-4 DP11 OUTPUT VPLUS DIODE 1 DP12 VMINUS OUTPUT DIODE 1 R10 VPLUS N23 300 I2 N22 N29 250UA Q10 N36 N39 N40 NMIN 2382 Q8 VPLUS N33 N32 NMIN 80 I1 N12 VMINUS 100UA R2 N59 N61 1K R19 N59 N60 1K * * DEVICE MODELS .MODEL ZEN D(IS=6E-16 CJO=1E-15 RS=1 BV=.2) .MODEL LAT5 PNP(IS=4E-15 BF=80 VAF=80 CJE=1E-13 CJC=6E-13 TF=3.5E-8 + RC=1.2E3 ) .MODEL PSUB PNP(IS=6E-16 BF=360 VAF=140 CJE=5E-13 CJC=2.5E-13 TF=2.5E-10 + RC=1.2E3) .MODEL NMAX NPN(IS=6E-16 BF=1200 VAF=140 CJE=5E-13 CJC=2.5E-13 TF=2.5E-10 + RC=0.6E3) .MODEL NMIN NPN(IS=6E-16 BF=300 VAF=140 CJE=5E-13 CJC=2.5E-13 TF=2.5E-10 + RC=0.6E3) .MODEL DIODE D(IS=6E-16 CJO=1E-15 RS=1) *.MODEL VSM2 VSWITCH(RON=1500 ROFF=1E7 VON=1.9 VOFF=2.1) *.MODEL VSM2 VSWITCH(ROFF=1500 RON=1E7 Vt={(2.1-1.9)/2} Vh={2.1-1.9}) *.MODEL VSM VSWITCH(RON=.1 ROFF=5E5 VON=2.1 VOFF=1.9) *.MODEL VSM VSWITCH(RON=.1 ROFF=5E5 Vt={(2.1-1.9)/2} Vh={2.1-1.9}) * .ENDS OPA549 * ***************************************************************************** .MODEL 1N4001 d +IS=1.22478e-08 RS=0.0414786 N=1.83369 EG=0.6 +XTI=0.05 BV=50 IBV=5e-08 CJO=1e-11 +VJ=0.7 M=0.5 FC=0.5 TT=1e-09 +KF=0 AF=1 .END

Hi Andy, Thanks for the reply. Yes, the problem came down to me not wiring up the Ilim and ref pins correctly. I have now simply tied them both together, and to ground, so to give the max limit of the op amp of 10 A (datasheet), and it now works fine. The problem just came down to me not reading the entire datasheet for the op amp in question - apologies for this. Not quite sure what you mean about the op amp not working correctly. Did you fix this? My circuit works fine now: https://easyeda.com/editor#id=42ccd8becba349dba7949c16eac996eb Thanks again, Tim

Apologies: wrong netlist. Try this one: *OPA549 test jig .tran 20u .param ILIM = 8 XU1 OUT OUT OUT IN V3_2 GND V3_2 ILIM XU1_9 D2_C D2_C OPA549 V3 GND V3_2 0 V2 D2_C GND 15 V1 IN GND PULSE(0 12 0 100n 100n 4.9u 10u) AC 1 0 R2 GND ILIM {75k/ILIM-7.5k} Rload OUT GND 1 D2 OUT D2_C 1N4001 D1 GND OUT 1N4001 .MODEL 1N4001 d +IS=1.22478e-08 RS=0.0414786 N=1.83369 EG=0.6 +XTI=0.05 BV=50 IBV=5e-08 CJO=1e-11 +VJ=0.7 M=0.5 FC=0.5 TT=1e-09 +KF=0 AF=1 ***************************************************************************** * OPA549 model from: * http: / / www.ti.com / lit / zip / sbom089 * ***************************************************************************** * OPA549 ***************************************************************************** * (C) Copyright 2011 Texas Instruments Incorporated. All rights reserved. ***************************************************************************** ** This model is designed as an aid for customers of Texas Instruments. ** TI and its licensors and suppliers make no warranties, either expressed ** or implied, with respect to this model, including the warranties of ** merchantability or fitness for a particular purpose. The model is ** provided solely on an "as is" basis. The entire risk as to its quality ** and performance is with the customer. ***************************************************************************** * * This model is subject to change without notice. Texas Instruments * Incorporated is not responsible for updating this model. * ***************************************************************************** * ** Released by: Analog eLab Design Center, Texas Instruments Inc. * Part: OPA549 * Date: 22JUL2011 * Model Type: ALL IN ONE * Simulator: PSPICE * Simulator Version: 16.0.0.p001 * EVM Order Number: N / A * EVM Users Guide: N / A * Datasheet: SBOS093E ? MARCH 1999 ? REVISED OCTOBER 2005 * * Model Version: 1.0 * ***************************************************************************** * * Updates: * * Version 1.0 : * Release to Web * ***************************************************************************** * CONNECTIONS: VOUT * | VOUT * | | INVERTING INPUT * | | | NON-INVERTING INPUT * | | | | NEGATIVE POWER SUPPLY * | | | | | REF VOLTAGE FOR CONTROL PINS (ES AND ILIM) * | | | | | | NEGATIVE POWER SUPPLY * | | | | | | | CURRENT LIMIT ADJUST * | | | | | | | | ENABLE / STATUS * | | | | | | | | | POSITIVE POWER SUPPLY * | | | | | | | | | | POSITIVE POWER SUPPLY * | | | | | | | | | | | .SUBCKT OPA549 OUT OUT2 - + V- REF V-2 LIM ES V+ V+2 Q2 N18 N16 N14 PSUB R3 N13 N14 8.4K Q1 N13 N12 N61 LAT5 R15 N40 VMINUS .168 Q9 VPLUS N34 N35 NMIN 2382 Q4 N25 N26 VMINUS NMAX 2 HCCVSP N47 N36 V475 -2650 HCCVSN N42 VMINUS V475 -2650 GNEGDRV VPLUS N37 N31 N36 -.00025 R4 N13 N15 8.4K GAINBLK N26 VMINUS N18 N19 .00175 R8 N19 VMINUS 1K R6 N17 + 1K R5 - N16 1K R7 N18 VMINUS 1K C2 N37 N36 11PF C1 N26 N25 31PF Q3 N19 N17 N15 PSUB Q7 VPLUS N37 N38 NMIN 128 R17 N38 VMINUS 180 D6 N32 N31 DIODE 18 D3 N27 N26 DIODE 1 D5 N27 N37 DIODE 10 D2 N23 N22 DIODE 6 D1 N60 N12 DIODE 6 VCLMP N27 VMINUS DC 1.1 VDUM N20 VMINUS DC 0 R9 N21 N20 35K C3 N21 N1N677 15PF FICOMP N37 VMINUS VDUM 1 D4 N29 N28 DIODE 1 R13 N28 VMINUS 750 Q6 N31 N29 N30 NMIN 2 R14 N30 VMINUS 300 R18 N39 N38 18 DCLAMP N37 N36 DIODE 1 R12 N1N677 N33 80 R31 N32 N34 1.9 V475 N43 Ref DC 4.75 GCLPGAIN VPLUS N51 N35 N47 .00015 Q11 N25 N51 N36 NMIN 1 C5 N51 N25 20PF D7 N48 N51 DIODE 1 VDP N48 N36 DC .65 R21 Lim N43 7500 D8 N49 N41 DIODE 1 Q12 N37 N41 VMINUS NMIN 1 GCLNGAIN VPLUS N41 N40 N42 .00015 V1I459 N49 VMINUS DC .65 C6 N41 N37 20PF DZ1 N31 N1N384 ZEN VCM VPLUS N59 DC 1.4 D9 N45 N46 DIODE 1 D10 N45 ES DIODE 1 IBES VPLUS N45 60UA R22 ES Ref 250K VBES N46 Ref DC 3.6 R16 N32 N36 500 R0 N35 N36 .168 VTHES N44 Ref DC 2.0 DP2 VMINUS - DIODE 1 DP1 - VPLUS DIODE 1 DP4 VMINUS + DIODE 1 DP3 + VPLUS DIODE 1 DP5 Ref VPLUS DIODE 10 DP6 VMINUS Ref DIODE 50 DP8 VMINUS Lim DIODE 1 DP7 Lim VPLUS DIODE 1 DP9 ES VPLUS DIODE 1 DP10 VMINUS ES DIODE 1 SVCS1 N36 OUTPUT N45 N44 VSM SVCS2 N32 N31 N45 N44 VSM2 CS2 VMINUS - 3PF CS1 VMINUS + 3PF CS3 - + 2.5PF Q5 N25 N22 N24 LAT5 Q20 VPLUS N1N667 N1N677 NMIN 8 R11 N1N677 N32 2K R1 VPLUS N24 300 R30 N25 N1N667 2K D20 N36 N1N384 DIODE 18 RDUMMY1 V+ VPLUS 1E-4 RDUMMY2 V+2 VPLUS 1E-4 RDUMMY3 VMINUS V- 1E-4 RDUMMY5 Out OUTPUT 1E-4 RDUMMY6 Out2 OUTPUT 1E-4 RDUMMY4 VMINUS V-2 1E-4 DP11 OUTPUT VPLUS DIODE 1 DP12 VMINUS OUTPUT DIODE 1 R10 VPLUS N23 300 I2 N22 N29 250UA Q10 N36 N39 N40 NMIN 2382 Q8 VPLUS N33 N32 NMIN 80 I1 N12 VMINUS 100UA R2 N59 N61 1K R19 N59 N60 1K * * DEVICE MODELS .MODEL ZEN D(IS=6E-16 CJO=1E-15 RS=1 BV=.2) .MODEL LAT5 PNP(IS=4E-15 BF=80 VAF=80 CJE=1E-13 CJC=6E-13 TF=3.5E-8 + RC=1.2E3 ) .MODEL PSUB PNP(IS=6E-16 BF=360 VAF=140 CJE=5E-13 CJC=2.5E-13 TF=2.5E-10 + RC=1.2E3) .MODEL NMAX NPN(IS=6E-16 BF=1200 VAF=140 CJE=5E-13 CJC=2.5E-13 TF=2.5E-10 + RC=0.6E3) .MODEL NMIN NPN(IS=6E-16 BF=300 VAF=140 CJE=5E-13 CJC=2.5E-13 TF=2.5E-10 + RC=0.6E3) .MODEL DIODE D(IS=6E-16 CJO=1E-15 RS=1) .MODEL VSM2 VSWITCH(RON=1500 ROFF=1E7 VON=1.9 VOFF=2.1) .MODEL VSM VSWITCH(RON=.1 ROFF=5E5 VON=2.1 VOFF=1.9) * .ENDS OPA549 * ***************************************************************************** .END