Yes but taking it up to 5V is not enough to turn it off.
No it will fry your arduino's output pin. You need to pull it up to 12V with a resistor and pull that resistor down with a transistor.
Yes absolutely But 15 V enhancement on a mosfet gate is close to the limit, You could put a 5V Zener from gate to collector in series with the existing resistor, cathode to the gate and pull up for a cheap level shifter a 1/4 w 5V1 zener would work well. The Problem is the diaellectric used fir the gate... It will 'Punch Through' at about 18 to 20 Volts and -10V is more than enough enhancement to fully turn on the gate... IMO but as always check the data sheet for max ratings. The Gate is very sensitive to electrical damage... of any kind.Doc
The mosfet I am probably going to use is here http://www.fairchildsemi.com/ds/FQ/FQP7P06.pdfIt shows the gate-source voltage as +25 so 15v should be ok. The 15v is going to be regulated with a voltage regulator.
Go look up a 1.5KE18, it's a Tranzorb, use it on the +15V source and if you are still concerned put a 18 V 1/4 W zener from gate to ground and you will be reasonably well protected. A silicon diode like a 1N5408 is a good idea as well for neg spike control. From +15V to ground, the anode, cathode to +15V... Otherwise you show a fair understanding of how to use a Mosfet.Doc
Yes, you can drive it as you were intending to, since 15v is well below the Vgs rating of 25V.If you do want to drop the gate voltage a little, then an easier way than using a zener is to replace the single pullup resistor by a voltage divider, e.g. 470 ohms between mosfet gate and 2n2222 collector, and 1K between mosfet gate and +15v (giving 10v Vgs instead of 15v).
If the load is highly inductive, don't forget to include a flyback diode in parallel with it.
If you put the zener between gate and source (cathode to source for p-channel) you'll protect the gate from overvoltage and from going negative (not that it minds going negative). QuoteOKQuoteFor source/drain overvoltage a TVS diode would be useful, but do we know if that's an issue even?I doubt that it will exceed 60v but it can be hard to say.
OKQuoteFor source/drain overvoltage a TVS diode would be useful, but do we know if that's an issue even?I doubt that it will exceed 60v but it can be hard to say.
For source/drain overvoltage a TVS diode would be useful, but do we know if that's an issue even?
The load is mostly capacitive but somewhat inductive and resistive as well (nice mish-mash).
QuoteThe load is mostly capacitive but somewhat inductive and resistive as well (nice mish-mash).No you can't say that.If you have a capacitive load and an inductive load the two cancel out according to the values of C and L and you end up with either a capacitive or an inductive load. In the case where they both are equal, that is a resonance point.