Why Does Base Current Start at 20uA at the Bottom in NPN Curve Tracers?

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The discussion centers on the confusion regarding the base current starting at 20uA at the bottom of the NPN transistor curve tracer. It is noted that for PNP transistors, both collector current (Ic) and collector-emitter voltage (Vce) are zero at the top right corner. The contributor suggests that the 20uA should actually represent the smallest Ic trace at the top, with base current (Ib) increasing with larger Ic values. This indicates a potential error in the marking of the graph. Clarification on this point is sought, especially in light of an approaching exam.
sandy.bridge
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Hello,
Hoping this can be cleared up quickly as I have my final exam in 1 hour. My question is for the attached image. I know for pnp transistors that ic=0, and Vce=0 at top right hand corner. However, one thing I don't understand is why the base current starts at 20uA at the bottom, rather than at the top. Help is greatly appreciated!
 

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Probably too late for your exam, but it looks wrong to me. 20uA should be the top (smallest Ic) trace, and Ib should step to larger values at the larger Ic values.
 
That's what I thought. Looks like whoever marked it was not paying attention.
 

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