Features, Applications: NPN silicon planar switching transistors. Fast switching devices exhibiting short turn-off and low saturation voltage characteristics. Mind the current maximums -- the JC501 maxes at 100mA vs the 2N3904's 200mA Ic -- and its lower fT -- 130 vs 270 (though, switching a fan on and off, that shouldn't be an issue) and you should be good. e: That's for 2N3904. 2N3906 is a PNP: you won't use an NPN in that slot. 2N7000 is an N-channel MOSFET, that's trickier.

2N3904 MMBT390 4 MMPQ390 4 PZT3904 NPN General Purpose Amplifier This device is designed as a general purpose amplif ier and switch. The useful dynamic range extends to 100 mA as a swi tch and to 100 MHz as an amplifier. Sourced from Process 23. Absolute Maximum Ratings* TA = 25°C unless otherwise noted All the part names for which the file 8850.pdf is a datasheet All the part names for which the file 8850.pdf is a datasheet