Driver transistor

icko

Member
2008-09-11 9:15 pm
Hello all,

What is your favourite driver low power transistor, or driver trannie?

I would like to find a transistor should be specified at 20W. Currently I am using 2sc4793/2sa1837 but would like to replace them due to that they are not linear hfe at 250-300mA bias. a bandwidth of 100MHz. TO220 (and not TO-3) would be nice too.

I was looking at the 2sc6200(or something close, can't remember right now) which seem really good (linear to 250mA if I could remember) but I can't find any place to source them.
 

icko

Member
2008-09-11 9:15 pm
Thanks to all of your suggestions.

Now I've looked through all suggestions.

Especially the 2SC5171/2SA1930 and 2SA1606/2SC4159 seem to be really sweet devices. The only downside is of course the lack of readily available spice models.

MJE15034/35 seem to be pretty good choice too, a bit low ft though. ~30MHz
 

mt490

Member
2010-06-09 2:32 pm
Low power... 20W...

I use 2SA1708/2SC4488, but they're in a Sziklai where the lower capacitance is useful. They're 1W devices though...

A1592/C4134 is the same die in a larger package, and A2205/C6099 is the larger die (higher capcitance) in a larger package.
 
Especially the 2SC5171/2SA1930 and 2SA1606/2SC4159 seem to be really sweet devices. The only downside is of course the lack of readily available spice models.

If you are relying on simulating an amp and choosing devices based on the simulator, you are wasting your time in my opinion. The accuracy and completeness of different models varies dramatically. You really need to either just pick the pair you like the look of from datasheets, or build a real amp and run real tests on it.

Simulation is only useful to compare topologies or change in operating levels etc with same devices, as a starting point to further develop by real building and test.
 

icko

Member
2008-09-11 9:15 pm
If you are relying on simulating an amp and choosing devices based on the simulator, you are wasting your time in my opinion. The accuracy and completeness of different models varies dramatically. You really need to either just pick the pair you like the look of from datasheets, or build a real amp and run real tests on it.

Simulation is only useful to compare topologies or change in operating levels etc with same devices, as a starting point to further develop by real building and test.

I agree, I don't use the simulator for evaluating trannies. Not i usuable circuits at least. looking at I/V curves I might, but rarely. I judge by the datasheet even though I know that's not good either. But since before i've tried it it's the only thing I got beforehand.

However it feels better using models of the transistors i plan to use, mostly because it's nice to be able to not have to do so much updating in the schematic going from sim phase to layout phase.

Ooh, And I should say that 20W was Tc and not Ta. Thats probably why mt490 was ridiculing me. :)

BR/ Icko.