Low Vgs FET

Can anyone advise ?

I’m building a low voltage battery powered project - two AA battery’s .
I need to use a P type FET in a circuit to switch off an Arduino and it’s display .

So I’m looking for 100mA or so FET , through hole, with a low Vgs threshold ( less than say 2v). I can find some 20A plus packages , but nothing smaller like say a TO92 package, unless I went to surface mount ( which I rather not use for hand soldering)

Can anyone suggest anything , I’ve not had any success in googling

TO92s are difficult to find :(.

I use these:


“ with a low Vgs threshold ( less than say 2v)”

Don’t look at threshold, look at Rds(on) with a ~2V Vgs with low Ω.

ex: AO3401

Yea , don’t really want surface mount though , not seen adapters before - but you still have to solder a surface mount device to it ..

I have seen several surface mount that would do the job , but trying to find through hole
In a small package .

Look at the NDP6020P (TO220 :frowning: ).

SMDs are soooooo simple to solder !

See time 5:50
(Also, specially for “ TheMemberFormerlyKnownAsAWOL” )

The problem is that nobody has made new TO92 mosfet designs in quite a while. All the improvements are going into SMD parts. So the only TO92s you can find that turn on at low voltages also have high RDSon specs. The TP2104 is a popular example, but as you put more current through it, you drop significant voltage, and generate significant heat.

I'd suggest you consider using one of the SOT-23 mosfets with an adapter board. My favorite is the DMP1045U, which is very nearly a perfect switch for Arduino type currents and even more.

I've never tried it, but in theory you might be able to parallel two TP2104s to reduce the voltage drop. But you're still going to be an order of magnitude worse than a modern SDM part.

Thx everyone, confirmed my thoughts - there aren’t any !! I think I’ll try a SMD and see how I go, I’m using TO22 versions atm - big tho !

Get wifey to buy you a head magnifier.

Is there a reason you can't use a regular bipolar transistor?

Thx everyone, confirmed my thoughts - there aren’t any !!

Thats been my conclusion too.

Try a PNP, 2N4403 or such.

I’ll look into the pnp thx Vce sat at 0.4 volts prob an issue. :frowning: