Hi,
I am trying to use EasyEDA and created a test project using 2n3904 transistor. But the sim results is way off my expectation. Here is the URL to the project: https://easyeda.com/editor#id=|453b6f20177b458490e819c012281c6c|a73489478bf84f94955a83eed5dd728f . According to the 2n3904 datasheet, it should have BetaDC at around 100. However, no matter how I tune the resistors, I always got the following result from the simulator. I particularly don't understand how the Vbe(-8.11e+00) and Ic(-4.16e-04) could be negative as showing below. Can someone shed a light on this problem?
Any advice would be appreciated!
Direct Newton iteration for .op point succeeded.
Semiconductor Device Operating Points:
--- Bipolar Transistors ---
Name: q1
Model: 2n3904
Ib: 8.37e-05
Ic: -4.16e-04
Vbe: -8.11e+00
Vbc: 6.29e-01
Vce: -8.73e+00
BetaDC: -4.97e+00
Gm: -1.29e-02
Rpi: 1.00e+12
Rx: 2.00e+01
Ro: 7.77e+01
Cbe: 3.54e-12
Cbc: 3.24e-09
Cjs: 0.00e+00
BetaAC: -1.29e+10
Cbx: 0.00e+00
Ft: 6.31e+05
Sorry about the incovenience but the collector and emitter spice pins had been reversed in the symbol.
It is correct now and your simulation runs OK.