Timer 555, Monostable Mode, one time timer

/*

/*
Timer 555, Monostable Mode, one time timer
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http://www.instructables.com/id/555-Timer/step2/555-Timer-Monostable-Mode/

                                        -t / (R*C)
(Voltage across Capacitor) = Vcc * (1- e          )
t = 1.1 * R * C

var C = 470uF
var Ra = 22k => 5.17 seconds

1. Connect power and ground to pins 8 and 1 of the 555 timer (red and black wires).  
2. Connect a 0.01uF capacitor between pins 5 and 1.  
3. Connect a 440uF capacitor between pins 1 and 6, make sure that the negative lead of the capacitor is connected to pin 1.  
4. Connect pins 6 and 7 with a jumper wire (green).  
5. Connect a 10K resistor between pins 7 and 8.  
6. Connect pins 4 and to Vcc
7. Connect LED+ to pin 3 and LED- to goun
8. Connect an LED and current limiting resistor in series from the output of the 555 to ground.  
9. Connect Wire the momentary push button switch in series with a 10K resistor between Vcc and ground.  
   Connect a wire (yellow) from the junction between the switch and resistor to the trigger pin 2

*/

function Get10P100(v) {
 return v*100/1000;
}
var capacitor = 47/1000/100  // 470 uF
var Ra = (10+Get10P100(10)) * 1000 // kOmh
var oneTimeDuration = 1.1 * Ra * capacitor
print("oneTimeDuration:"+oneTimeDuration);

Interresting Links 

• 555 Calculator