Hi
I am designing a multi stage optically triggered coil gun for a school project
I have an optical trigger which drops the voltage fron 12v to 0v
this triggeres the comparator and then an emmitter follower
my problem is this
I want to limit the maximum pulse width incase the projectile gets stuce infront of the sensor
I have an and logic in the circuit which could be used to limit the pulse
I need a one shot timer with the pulse length of about 0.5s that cannot be retriggered until it is reset
I don't mind what the reset is
it could be
a) a time period passing
b)a button
c)Vtrigger rising abouve a certain value
so far the only circuit I've found has a large parts require,ent
two 555's some resistors and caps
the first 555 cannot be retriggered until the pulse of the second 55 has run out.
this circuit
**broken link removed**
anyone got a solution with a lower part count?
I am designing a multi stage optically triggered coil gun for a school project
I have an optical trigger which drops the voltage fron 12v to 0v
this triggeres the comparator and then an emmitter follower
my problem is this
I want to limit the maximum pulse width incase the projectile gets stuce infront of the sensor
I have an and logic in the circuit which could be used to limit the pulse
I need a one shot timer with the pulse length of about 0.5s that cannot be retriggered until it is reset
I don't mind what the reset is
it could be
a) a time period passing
b)a button
c)Vtrigger rising abouve a certain value
so far the only circuit I've found has a large parts require,ent
two 555's some resistors and caps
the first 555 cannot be retriggered until the pulse of the second 55 has run out.
this circuit
**broken link removed**
anyone got a solution with a lower part count?