Help selecting transistor

I don't know if such exists...

I'm looking for an NPN transistor with a collector current of about 150mA when saturated at 5mA to its base (β = 30). The collector voltage needs to be 12V when 8V applied to its base.
It also needs to handle a current increase of 15mA to its base via a selector switch.

Thanks
Jeff

R2-D2 said:

I don't know if such exists...

I'm looking for an NPN transistor with a collector current of about 150mA when saturated at 5mA to its base (β = 30). The collector voltage needs to be 12V when 8V applied to its base.
It also needs to handle a current increase of 15mA to its base via a selector switch.

Thanks
Jeff

Click to expand...

8 volts from base to emitter will destroy a transistor.

Hi Ron,

Thanks for the response.
I forgot to consider that there will be a resister applied directly to its base which drops majority of the voltage to it for safe operation. I think a 2N3904G would do for what I need according to its specs but not sure:

Collector Emitter Saturation Voltage, Vce(sat):0.3V
Power Dissipation, Pd:0.625W
DC Current Gain Min (hfe):40
C-E Breakdown Voltage:40V
Collector Current:0.2A

Datasheet:
https://www.electro-tech-online.com/custompdfs/2009/01/2N3903-DPDF.pdf

Jeff

I would use PN2222A. Most BJTs specify saturation voltage with forced beta=10, which means Ib=Ic/10. With Ic=150mA and Ib=5mA (forced beta=30), it will almost certainly work, but saturation voltage is not guaranteed.

Good morning Ron,

Thank you for that link to the data sheet.
The PN2222A looks good - I'll definitely try that one out.

Happy New Years!
Jeff