Residual Current of a BJT

[Nandika]

Hello Friends,
I did a practical for residual current of a BJT as procedure of guide book.But,I some things are hard to understand.
We use a PNP Ge transistor.Because,A Si transiator has small residual current.therefore we cant measure it using normal multimeter or oscillescope.

First,We measure E-C current while base is open.as fallowing picture.We called it I_CEO.

ICEO.png (1.46 KiB) Viewed 5867 times

We got 2.13mA for the result.

Second,We measure I_CES
According to following diagram.

ICES.png (731 Bytes) Viewed 5867 times

We got 0.732mA for the result.

Third,We measure I_CER

ICER.png (921 Bytes) Viewed 5867 times

We got fallowing result.
For 100k-->11.80 mA
For 10k-->11.86 mA
For 1k-->11.87 mA

Fourth,We measure I_CEV

ICEV.png (1.05 KiB) Viewed 5867 times

We got,
R(k)----I_CER(mA)----V_BE(V)
100----11.80----0.94
10----11.86----5.90
1----11.87----10.88

Now,
I can understand I_CES and I_CEO
But,
I_CER in problem.
As I think,We are increasing base resistance,base current decrease.Therefore collector current increase. Unfortunately,It's not explain my assumption.
Another problem in I_CEV
In this situation B-E junction become reverse bias.

I want some explanation for Third and Fourth situation.

Thanks

[SemiconductorCat]

>>
>> Another problem in ICEV
In this situation B-E junction become reverse bias.

it is not as I could see, check and review it back.
Anyway I'm not familiar with this particle, somebody experienced will answer your question.
If 48h gone without a proper answer, you could answer it at stackexchange.

[Neo]

The name should be Current Residual. I found a nice explanation here.
http://www.premiumorange.com/daniel.rob ... eurs4.html

[Nandika]

Thank Neo...
It's really useful link.
I'm trying to understand well.

[Nandika]

>>
>> Another problem in ICEV
In this situation B-E junction become reverse bias.

it is not as I could see, check and review it back.
Anyway I'm not familiar with this particle, somebody experienced will answer your question.
If 48h gone without a proper answer, you could answer it at stackexchange.

Sorry... my circuit diagram is incorrect.
Right one is following.

ICEV.png (1016 Bytes) Viewed 5826 times