Is it possible to plot Ic=f(Vbe) with Ib as parameter shown on the plots in stead of Vrb

[hugocoolens]

I'm experimenting with the curve tracer adapter and the WaveForms software currently. Is it possible to plot Ic=f(Vbe) with Ib as parameter shown on the plots instead of Vrb? That's what you normally see in datasheets with the output characteristic of a bipolar transistor, Vrb is not interesting as such.

 

kind regards,

Hugo

[attila]

Hi @hugocoolens

In this setup the Vrb is controlled by a step voltage signal. The Ib can't be controlled in such way only measured.

[hugocoolens]

56 minutes ago, attila said:

Hi @hugocoolens

In this setup the Vrb is controlled by a step voltage signal. The Ib can't be controlled in such way only measured.

 

[hugocoolens]

Does this mean that the output characteristics Ic=f(Vce) are not given for fixed steps of Ib as it is on a regular curve tracer? Is there a method to (post)process the data such that we get "regular" output characteristics (i.e. one characteristic for each fixed Ib value) ?

 

kind regards,

Hugo

[hugocoolens]

On 3/27/2023 at 3:21 PM, hugocoolens said:

Does this mean that the output characteristics Ic=f(Vce) are not given for fixed steps of Ib as it is on a regular curve tracer? Is there a method to (post)process the data such that we get "regular" output characteristics (i.e. one characteristic for each fixed Ib value) ?

 

kind regards,

Hugo

So, may I conclude?:

1. The software does not display the real output characteristics when using the curve tracer module

2. It is not possible to display the real output characteristics with the curve tracer module

3. To display the real output characteristics a stepped current source for Ib would be  necessary

Can anyone here confirm this?

kind regards,

Hugo

[attila]

Hi 

1,2. The real characteristics are measured but not with step Ib but Vrb. The Ib results from the drop across the Rb reference resistor, like in the drawings on the right:
3. Yes

[hugocoolens]

On 4/3/2023 at 5:05 PM, attila said:

Hi 

1,2. The real characteristics are measured but not with step Ib but Vrb. The Ib results from the drop across the Rb reference resistor, like in the drawings on the right:
3. Yes

Thanks for answering. Let's agree to disagree on this, but I wouldn't call this "the real" output characteristics because when you look them up in a datasheet the output characteristics will always be given with a stepped Ib (thus making them independent from a Vrb and rb).  It would of course be interesting to see how much they differ from each other for certain values.

kind regards,

Hugo