# Transistor Question

Discussion in 'Homework Help' started by celect, May 31, 2005.

1. ### celect Thread Starter Member

May 31, 2005
18
0
What would happen if I replaced a transistor with one that has a lower H
i

vaule?

2. ### mozikluv AAC Fanatic!

Jan 22, 2004
1,437
1
hi

pls clarify what you mean by H i.

3. ### celect Thread Starter Member

May 31, 2005
18
0

h (hybird)
h Parameters h would be the input resistance
i

4. ### Brandon Senior Member

Dec 14, 2004
306
0
The input resistance is not something you go around checking usually. Unless your loading down a circuit or need precision sound or something, it shouldn't make a difference.

Give us an idea what your trying to do, might be able to help you out better.

5. ### celect Thread Starter Member

May 31, 2005
18
0
This is a homework question asked what would I expect to happen,

6. ### Brandon Senior Member

Dec 14, 2004
306
0
Ahh.. Same here. Never heard of an H value. Was always gm, Rpi, Re, Ru, alpha, and beta.

In the end, nothing really. The transistor would just use less current in the base. You could have a larger fanout in a digital circuit. mmm.. not sure what else.

7. ### pebe AAC Fanatic!

Oct 11, 2004
628
3
Give a vague answer to a vague question. Just say "Maybe".

8. ### mozikluv AAC Fanatic!

Jan 22, 2004
1,437
1
hi

lets take a specific npn transistor like the 2SC1815R it has a minimum beta of 200 and a max of 750 depending on the collector current. if you were to replace that with the same transistor # but with a different suffix letter like letter Y, would you still have the same performance as the original assuming that none of the items connected to the transistor were replaced. the answer is no.