Swtpc Universal Tiger Improved And Simulation

[PB2]

I decided to simulate the SWTPC Universal Tiger using newer high speed, high beta output devices. Here is an old thread with the schematic: Universal Tiger

It does not simulate well with the original output devices, lots of crossover distortion and so on. However, I don't trust the On-Semi models for the old devices. The newer devices make a dramatic improvement. I was only able to do this using Andy C's improved, actually degbugged, models for the output devices, thank you AndyC: Evaluation results: MJL3281A/MJL1302A SPICE Models

I don't know if I'll finish this, but attached is the LT-SPICE model for the improved output stage. I doubled up on output devices so that it will be safe driving 2 ohm loads, and increased the driver bias current. I suggest rail fuses for protection and of course a front end is required. I don't trust the output stage for thermal stability, it should be analyzed. I thought people might be curious to see it in simulation.

Andy's models must be added to the LT-SPICE library, as well as these below. Anyone checked the mje15034 and mje15035? :

.MODEL mje15034 npn IS=3.92866e-12 BF=260.938 NF=1.02215 VAF=15.3399 IKF=0.160087 ISE=1e-08

NE=2.54491 BR=26.0938 NR=1.10885 VAR=153.399 IKR=1.60087 ISC=1e-08 NC=1.89024 RB=0.41209 IRB=0.1

RBM=0.41209 RE=0.0001 RC=0.208002 XTB=0.897431 XTI=1.39234 EG=1.206 CJE=1.61534e-09 VJE=0.698417

MJE=0.382854 TF=1.03079e-09 XTF=1000 VTF=100000 ITF=42.9041 CJC=1.04458e-10 VJC=0.441587 MJC=0.23

XCJC=1 FC=0.8 CJS=0 VJS=0.75 MJS=0.5 TR=1e-07 PTF=0 KF=0 AF=1


.MODEL mje15035 pnp IS=5.81508e-15 BF=313.373 NF=0.85 VAF=40.5017 IKF=0.897023 ISE=6.74258e-16

NE=1.04249 BR=0.958017 NR=0.894461 VAR=148.639 IKR=7.05393 ISC=6.74258e-16 NC=2.84461 RB=3.62039

IRB=0.1 RBM=0.1 RE=0.000923293 RC=0.233799 XTB=2.92628 XTI=1.01325 EG=1.17461 CJE=1.5597e-09 VJE=0.99

MJE=0.554057 TF=1.35882e-09 XTF=1000 VTF=467.207 ITF=58.3338 CJC=1.58888e-10 VJC=0.4 MJC=0.23

XCJC=0.786287 FC=0.8 CJS=0 VJS=0.75 MJS=0.5 TR=1e-07 PTF=0 KF=0 AF=1

Pete B.

[PB2]

Attached is the LT-SPICE file for the original design. I used On-Semi models for output devices, and substituted diodes as required to match the library.
SWTPC upgraded the design using 2N5210s in the front end, so that is what I used.
I could not find models for the old 40409/40410 but they were similar to the 2N3053 and I found a model for it at Duncan's site. I made an exact compliment to do the other part, here's what I used. If anyone has better models please speak up:

.MODEL 2N3053 NPN (IS=71.1F NF=1 BF=260 VAF=113 IKF=.42 ISE=27.3P NE=2 BR=4 NR=1 VAR=20 IKR=.63
RE=73.6M RB=.294 RC=29.4M XTB=1.5 CJE=79.2P VJE=1.1 MJE=.5 CJC=25.5P VJC=.3 MJC=.3 TF=858P TR=596N
Vceo=40 Icrating=700 mfg=DUNCAN)

.MODEL COMPN3053 PNP (IS=71.1F NF=1 BF=260 VAF=113 IKF=.42 ISE=27.3P NE=2 BR=4 NR=1 VAR=20 IKR=.63
RE=73.6M RB=.294 RC=29.4M XTB=1.5 CJE=79.2P VJE=1.1 MJE=.5 CJC=25.5P VJC=.3 MJC=.3 TF=858P TR=596N
Vceo=40 Icrating=700 mfg=DUNCAN)

Pete B.

[PB2]

Originally posted by PB2
It does not simulate well with the original output devices, lots of crossover distortion and so on. However, I don't trust the On-Semi models for the old devices.

I should mention that it does not simulate well open loop, the feedback does a fairly good job covering the crossover distortion, and higher bias helps.

Pete B.

[PB2]

I would use the Jensen 990 up to the VAS as an improved front end for this design, and run it on +/- 30 V derived from the main supply. I'd remove the diff pair emitter inductors, and increase the degeneration. Also decrease the VAS degeneration, and redo the HF compensation. Compensation should not be as critical since it does not have to be unity gain stable, and the open loop gain can be lower.

I welcome constructive comments/brainstorming.

I'll use SANKEN 2SC3284/2SA1303 for outputs if I build the improved version which are 125W and this is another reason for doubling up or even more outputs.

Pete B.

[djk]

I can't open any of your files.

[Original Burnedfingers]

I cannot open your files either.

[jmateus]

Me neither....

[PB2]

Here's another try, both files are in the .zip, I used XP to ZIP them:

[djk]

The files are all empty.

[PB2]

Originally posted by djk
The files are all empty.

Sorry, don't know what's going on.
I'm able to download them, extract and they work in LT-SPICE, and I can view the file content in a text editor. Any suggestions?

Pete B.