Anyone know a strong P channel MOSFET (about 40v, 1A, logic level) ?

[diode]

Hi,
Can anyone here think of a good logic level P channel MOSFET that can deal with about 40v, 1A? 
Have been searching the internet for hours and thought to try here..
Thanks!

[fungus]

Can anyone here think of a good logic level P channel MOSFET that can deal with about 40v, 1A?  

I think most of them can handle that much power. Probably quite a few BJTs, too.

[johnwasser]

You can do parametric searches at both DigiKey.com and Mopuser.com.

At DigiKey I put in the search term 'logic level mosfet'.

Then clicked on "FETs - Single".

Then under FET Type selected "MOSFET P-Channel"

Under Vdss I selected for 40V,45V,or 50V

You can figure out the rest.

[AlxDroidDev]

I'd say nearly all of them. It'd be more trouble to find one than CAN'T handle that than one that can.

1A at 40V is nothing for a MOSFET, provided they have a cooling rib.

Here's a brief list from Vishay: http://www.vishay.com/mosfets/p-channel/v-ds-gteq-neg31-v-lteq-neg80-v/

[Riva]

How about this.

[AlxDroidDev]

How about this.

Isn't the IRF520 a N-channel MOSFET ? I believe the OP needs a P-channel.

[diode]

Thanks all! Will look at those resources - there are so many.

Was just wondering if there is one or some that are particularly good / easy to interface / power efficient etc.

(like for example the IRF540 N Channel seems to come recommended as an N Channel)

Reading into it also seems they have become much better over time.

ps. yes the IRF520 is N.

[CrossRoads]

You are using this as a high side switch device?
To drive from an Arduino pin, you will need NPN or logic level N-channel to pull the P-channel's gate low to turn it on, with pullup resistor to 40V to turn it off.
I posted a circuit yesterdy to do that, for driving a halogen lamp.

[CrossRoads]

Replace the PNP with P-channel MOSFET

[diode]

CrossRoads - I want to connect them to a TLC5940. Am presuming a P channel MOSFET can connect straight to a TLC.

[CrossRoads]

TLC5940 datasheet says it needs some minimal load to switch properly.
Use a low enough value resistor as the Pullup resistor to 40V to meet that.
The TLC5940 will act as the NPN transistor here.
Have not tried this myself, wire up just 1 MOSFET to start and see  how it works.

[diode]

Thanks for your thoughts!
Not sure what you mean with the minimal load?
Haven't got a P channel MOSFET at hand so have to get one and try tomorrow.

[sparkylabs]

What exactly are you trying to do with the mosfet ? if your switching loads then low side switching is best if possible because N channel devices are cheaper and have better characteristics.

[JoeN]

What exactly are you trying to do with the mosfet ? if your switching loads then low side switching is best if possible because N channel devices are cheaper and have better characteristics.

But a TLC5940 is already a low-side PWM controller that sinks current.  So for a matrix, as an example, if the columns are cathodes you use the TLC9540 to control the columns.  This leaves you to control the rows (anodes), on the high side.  How do you use N-channel for that?  The general way to solve that from what I have seen is P-channel MOSFETs or maybe darlingtons on the high side to source current.

[sparkylabs]

yes in that case it has to be high side. unless the LED's are powered from 5v he needs level shifting too as suggested above