Ignoring the load, it might work if you used a diode in series with the input pulse. They're using the /RESET input a bit unconventionally.
With the load, it's not happening. You already have 1.7V (typical) drop at only 100mA. Maybe you'll get 300mA or 400mA into the motor. You're supposed to use a series diode for inductive grounded loads (plus a flyback diode across the motor), so that would drop even more voltage. The dissipation in the 555 will be quite high but it might not fail right away with such short pulses. The motor won't get anywhere near full current. Stall current is going to be higher so unless it's almost unloaded (a fan maybe) the motor may not move at all.
Maybe a 555 switching a logic-level power MOSFET would work for you, not much more complex.
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I don't think that the NPN transistor in the NE555 can sink anything like o ne ampere.
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says +/-225mA is the absolute maximum rating, and anything over a few mA ta kes the transistor out of saturation.
I suspect you need to separate the timer function from the current driver - for wimpy currents the NE555 could be used for both jobs, but for your cur rent you more or less have to drive a biggish Darlington transistor or a lo w-on-resistance MOSFET. An NE555 can be used to do that job, but so can an y other monostable, though few are as cheap (or as nasty) as the NE555.
Adding a second transistor to the driver to make a two transistor monostabl e would probably offer the cheapest and simplest solution
The logic fet should be in the neighborhood of 2.5V switch on to drive the gate. Keep in mind this fet must act as a sink, the low side for your motor.
If you don't see enough (+) drive coming from output of the timer you can add a R from the Vcc (pin 8) over to the output to bring up the gate drive to the power supply level. The timer will simply pull it to common when the output is off.
Since you don't need any current except for the charge in the gate to turn on the gate, the pull up R is of high a value.
You can get mos fets in small packages that cover your needs, just glue it to the back of the timer after you snot the solder on it.
I'd also suspect you are using this 5 Volt pulse for making a one shot from it along with using it for power?
I can't help thinking this is some sort of devious device, I guess my amagination is working overtime.
It's not devious at all. It's a bubble-machine, small enough to be carried by a quadcopter. The qaud I have has +, gnd, and pulse available; the bubble machine has + and gnd.
The smallest solid-state relay I saw with a quick google was 7g - too much weight.
The voltage drop across the NE555 output transistor is going to get pretty high above 200mA so the current probably won't get to 1 amp anyway - the 2A discrete transistor is much better idea.
Half-wit. It was my second contribution to the thread, and reiterated the point - made in passing in my first contribution - that the NE555's output transistor would be well out of saturation by the time you got to 1A.
pretty high above 200mA so the current probably won't get to 1 amp anyway
- the 2A discrete transistor is much better idea.
he point - made in passing in my first contribution - that the NE555's out put transistor would be well out of saturation by the time you got to 1A.
The colloquial meaning of "half-wit" is that it applies to somebody who is cognitively challenged - as you certainly are. There's no implication that the wits that you have left are up to much.
Trying to extract a quantitative evaluation from an idiom - which "half-wit " certainly is - when an idiom, by definition, means something different fr om the naive interpretation of the word-cluster that forms the idiom - is p recisely the sort of dim-witted trick you pull all the time, because you do n't have the sense to know better.
You must have a pretty lame newsreader if it doesn't automatically word-wrap to the size of the window. Or maybe you haven't found the magic setting that turns it on? I use Windows Live Mail, which is pretty lame, but word-wraps with no problems.
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