# Transistor characteristic curves (Vce/Ic curves)

#### PaulEngineer

Joined Dec 21, 2016
217
Hi everyone. Is there any website that shows each transistor characteristic curves? I search like almost on all the internet datasheets (especially alldatasheet.com) but very few of them provide Ic/Vce curves, like one or two of them, out of 30-40 semiconductor manufacturers. But even these who show them, doesn't provide clear image information about these curves. So is there any website that provide these curves? For example.. 2N3904 or 2N2222. I have searched almost every semiconductor brand.. There are no characteristic curves even though the manufacturers should have been provided them. And this is really frustrating to be honest. Unless if there is any way to draw characteristic curves at home, or if i search wrong website that provides datasheets. I heard there are devices that can create characteristic curves, but they are very expensive. I have an oscilloscope Hantek DSO5202B but it cannot create characteristic curves. There are some keysight oscilloscopes that can provide these curves, but they are cost a lot. So is there any website that provide them? Thank you.

#### Jony130

Joined Feb 17, 2009
5,404
To design a circuit with BJT you do not need any transistor characteristic curves.

#### Ian0

Joined Aug 7, 2020
5,819
What’s your application ? Why do you need Vce/Ic ?

#### crutschow

Joined Mar 14, 2008
30,420
You can simulate them, of course, with a Spice simulator such as LTspice (example below), but if you want curves from real transistors, then a search for transistor curve tracer adapter shows some for sale.
But, as noted, you don't need the curves to design a circuit.

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#### Audioguru again

Joined Oct 21, 2019
4,921
Each transistor part number has a wide range of specs for example a 2N3904 has an hFE from 100 to 300 at 10mA, 1V Vce and 25 degrees C. The datasheet also has graphs of the affect of temperature on "typical" spec'd ones.
You must design the circuit so that all transistors work in your circuit, not just ones that have "typical" specs.

#### dl324

Joined Mar 30, 2015
14,897
any way to draw characteristic curves at home
You can create your own by doing what a curve tracer does. Vary base current and Vce and plot the data.
I heard there are devices that can create characteristic curves, but they are very expensive.
Used curve tracers can be found on eBay for $200-300 these days. In the past, you could get them for around$50 (I bought 2 in that price range and one was within the past 3-4 years).

But, as noted, you really don't need them in most cases.

#### PaulEngineer

Joined Dec 21, 2016
217

#### ci139

Joined Jul 11, 2016
1,867
you should first look up how such characteristics are obtained , and for what they are used
it is obvious you cannot have Vce variation with an ideal Vc supply
also the Vce depends on the series collector resistance (and the Vc supply)
the higher the series Rc - the lower the Vce
at some point the series Rc starts significantly limiting the possible Ic

moreover - the Ic variation causes the junction temperature variation , that in turn causes the h.FE and Vce variation . . .

you need the context and the range the characteristics can be applied (are valid at)