### Communities

tag:snake search within a tag
answers:0 unanswered questions
user:xxxx search by author id
score:0.5 posts with 0.5+ score
"snake oil" exact phrase
votes:4 posts with 4+ votes
created:<1w created < 1 week ago
post_type:xxxx type of post
Notifications
Q&A

# Thermal stability coefficient

+0
−3

The thermal stability coefficient is defined to be:

$S = \frac{dI_{C}}{dI_{CBO}}$ where $I_{CBO}$ is the reverse current of the BJT when voltage isnt applied to the base of the BJT.

In case of a BJT biased with 2 sources $I_{C} = \beta \cdot I_{b}+(\beta +1)I_{CBO}$

However my textbook says that $S = \frac{1+\beta}{1-\beta\frac{dI_{b}}{dI_{C}}}$

however I dont get why that is the case.Any help?

Why does this post require moderator attention?
You might want to add some details to your flag.
Why should this post be closed?

#### 2 comment threads

Post Feedback (1 comment)
link your definitions (2 comments)

## 1 answer

+0
−0

If "base voltage isn't applied" then Ib=0 & dIb=0 then the proposed formula with Ib is not logical.

Why does this post require moderator attention?
You might want to add some details to your flag.

#### 0 comment threads

This community is part of the Codidact network. We have other communities too — take a look!

You can also join us in chat!

Want to advertise this community? Use our templates!

Like what we're doing? Support us!