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LTSpice question

I've noticed some LTSpice simulations indicate a higher than expected transistor current gain (HFE). I drew up a simple emitter follower circuit using a 2N3904 transistor and it indicates the emitter current at 1.6 amps (3 volts across 2 ohms in the emitter) and a base current at 24 milliamps for a HFE gain of 66. I didn't know a little 2N3904 transistor would operate at 1.6 amps and still have a gain of 66. What am I doing wrong?

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Reply to
Bill Bowden
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LTspice takes liberties with models to speed up simulations. Try a non-LTspice transistor model... they'll run just fine in LTspice and compare. Does the LTspice model have a term "IKF"? ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
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Reply to
Jim Thompson

LTspice is super MAN, it knows no bounds!

Jamie

Reply to
Maynard A. Philbrook Jr.

There sure is and that LIB entry does have it set to 0.4?

Jamie

Reply to
Maynard A. Philbrook Jr.

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Yes, the LTspice modle has a term of IKF assigned to a value of 0.4. I found a non-LTspice model for the 2N2905A which was of interest and copied and saved the text using Notepad.. Not sure what filename to use or LTspice directive. Still working on those problems.

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Reply to
Bill Bowden

Hey, LT Spice thinks a 1N914 can rectify 100 kilovolts!

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John Larkin         Highland Technology, Inc 

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http://www.highlandtechnology.com
Reply to
John Larkin

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