I have a question:
Tonight for laughs I built a triangle wave generator (floating above ground) to the input of a unity gain op-amp which is in a closed loop system.
On the op-amps output, I have a 100ohm resistor connected to the base of a
2N3507, 9 volts on the collector and the emitter is fedback to the inverting input (for the closed loop system). The emitter's output is also connected to a minature fan that draws about 0.5 amps at full on.My idea was to slow the fan and then speed it up with the triangle wave generator (changing the ramp time by RC). But I ran into a problem: the transistor gets as hot as a pistol.
The datasheet has an Ic of 3A and yet I'm only driving (let's even call it
1A) not even half the maximum rating.Should this be connected to a heat sink and if yes, how would I have known this by reading the datasheet?
Thanks in advance