Not sure what I need to finish this.

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blueredmx

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I'm not sure exactly what i'm looking for, so I came here for help.

For the circuit i'm building, I have a micro-switch that is controlling a solenoid.

I only want the solenoid to be active for a few milliseconds, no matter how long the switch is active.

What sort of chip would I be looking for to achieve this, would this require a 555 one shot circuit?

Thanks, Chad.
 
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Yes, you could do it that way or you could go with an edge triggered single shot multivibrator. Build it yourself out of discreet components and the transistors could be selected to directly drive the solenoid. Otherwise, use a chip version and use its output to control a driver transistor. Sorry, I don’t have my reference materials with me so I can’t look up any numbers for you.
 
Thanks very much man, I'm only slightly literate when it comes down to actual components. Ill check out what you mentioned.
 
Hi,

here is a circuit which might suit your needs.

The output is unaffected by additional inputs pulses while it is active. (non retriggerable monostable)

The output is high for 5.163ms.

D1 is optional, but recommended to clip positive going pulses.

Boncuk
 

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If the time period accuracy or temperature stability isn't critical, you could use a simple RC circuit to control the base of the transistor that drives the solenoid. That would require two resistors, a capacitor, and a diode.
 
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