npn transistors

Thread Starter

duxbuz

Joined Feb 23, 2014
133
Hi

Can anyone tell me why the main difference is between these 2 transistors:

http://cpc.farnell.com/on-semiconductor/mps2222a/transistor-npn-to-92/dp/SC06675?Ntt=sc06675

http://cpc.farnell.com/on-semiconductor/p2n2222ag/transistor-npn-to-92/dp/SC12549?Ntt=P2N2222A


I know that's an open ended question. I am trying to work out why I would have bought the mps2222a, I can only imagine I was buying 2222a transistors and I bought them to cover the bases as I don't rightly know enough to make a proper informed purchase when it comes to components.

I think at the time I was reading about using transistors to switch small motors on with microcontroller pins.

Are the mps2222a transistors going to perform the same?

The mps2222a is named a general purpose transistor, and the pins seem to be numbered different, but it is still npn not pnp.

The psn2222a is named and amplifier transistor.

Does that mean the mps2222a has no amplification characteristics.

Thanks
 

ISB123

Joined May 21, 2014
1,236
Every transistor can act as amplifier and switch. I would buy MPS because it has greater Hfe while having the rest of the specifications same as other one.But still it all depends on the circuit design and how much current it needs to pass and how much current is at the base.
 

Thread Starter

duxbuz

Joined Feb 23, 2014
133
Thanks

base current would be up to 40 mA (milliamps) for microcontroller pin I think.

The Hfe looks the same to my untrained eye.

Is there a reason the pins are reversed?
 

ISB123

Joined May 21, 2014
1,236
Pinout is different because it isn't standardized only the package is.If you apply 1mA on transistors base you will get amplification of 100mA.What kind of load you want to drive?
 

Thread Starter

duxbuz

Joined Feb 23, 2014
133
Thanks for your help

The motor was bought from a supplier with no real specification other than
voltage 1.5 to 4.5v, current 0.083 to 0.41A

so 83mA min to 410mA

I am not going down the 'I thought the transistor was in saturation' route again right now, as I have not had my electronics head on for months!

I never really reached total clarity the last time I asked that one!
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
Hi

I think at the time I was reading about using transistors to switch small motors on with microcontroller pins.

Are the mps2222a transistors going to perform the same?
Have you looked at something like the 2n7000? designed for this type of application.
Or IRL520/530 for higher current.
Max.
 
Top