- #1
mikehsiao789
- 14
- 0
Hello, I am trying to design a circuit that can measure the BETA of a PNP and NPN transistor, I have an ammeter, and I have a design that makes IB going in 0.1mA, so that the current IC of the collector with a shifted decimal is the Beta we would like to measure. So I used a current source, and designed a circuit (a picture of the two circuits I designed is attached to my blog here: http://vantraveller.blogspot.ca/). However, I don't think the current source is correct.
The meter I am making should be able to measure any NPN or PNP transistor, but with the current source I am using, sometimes the value of IB changes, which it shouldn't.
I am thinking that maybe the current source is wrong. Is there a way to correct the current source? Is there an easier way to fix IB so that I do not need to use a current source? Thank you so much!
The meter I am making should be able to measure any NPN or PNP transistor, but with the current source I am using, sometimes the value of IB changes, which it shouldn't.
I am thinking that maybe the current source is wrong. Is there a way to correct the current source? Is there an easier way to fix IB so that I do not need to use a current source? Thank you so much!