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Yes it is, but it has a low gate-source threshold for a 4.5V rated MOSFET, it kind of slips in just under the wire. Most 4.5V rated MOSFETs don't fare to well on a single cell or parallel cells. They'll work, but they waste a lot of power not being in the flat part of the curve when battery voltage drops down. A 4.5V rated MOSFET does become a bigger issue with single or parallel cells in terms of a short circuit condition. Voltages drops quite a bit at the battery during a short circuit condition. In turn that drops gate-source voltage down as well (unless a driver or doubler is used). In that case you get pretty far left into the curve so the MOSFET is not only carrying much more current than normal, it's also into the active region where on-state resistance is much higher. It's like a double whammy, much greater currents and much greater on-state resistance.You really can't assume your MOSFET will handle a short okay once a fuse is placed inline. It's something you have to check at the risk of burning some perfectly good MOSFETs.
I use Vishay MOSFETs a lot. I like them, they seem to have the best specs for the things I look for. That's both for high speed stuff like in switching power supplies or for user power switches such as a trigger switch in a mod. After Vishay it would be TI. They don't have much in the way of P-channels, but they have really nice N-channels.For a high side user power switch using single or parallel cells, my go-to transistor is the Vishay Si7157DP. For low side switching with single or parallel cells it would be the Vishay SiR404DP.
I understand that leaded parts are most convenient for free-hanging stuff, but unfortunately leaded parts are becoming obsolete. At some point you just won't see them anymore. The solution for free hanging stuff and SMD parts is to build a small host board. You'll find it's a pretty quick operation to etch one out and either reflow or hand solder an SMD MOSFET and wires to it. Granted it's more work than using a leaded part, but if you want to step into the 21st century and use the best parts available, that's what you have to do.
Yes I did and while I am no genius on the subject it looked really close considering you said one battery. Forgive me for trying to help.
Well, if making host boards is a problem, you could send them out to Osh Park. For something that small it would be like a dollar for three of them, $8 would get you 24 of them. I doubt your time is that cheap, is it?Otherwise, there are no 2.5V leaded MOSFETs that I've seen. Inexpensive 2.5V rated MOSFETs came out after through hole components were already well on the path to obsolescence. No makers offer them in a leaded package, at least for stock on store shelves.
There's other ways to handle short circuit detection with a mod that utilizes an MCU. In that case it's not necessary to rely on a fuse. It's possible to detect a fault and open the circuit quickly, as in a few thousandths of a second. Even with a worst case, it takes at least a couple seconds for the MOSFET to heat up enough to burn out. A higher rated PTC fuse during a softer short can take longer than that to react.
100 Amps for 1mS every second has the same energy as 100mA continuously, not much.