- #1
ashankan
- 3
- 0
i'm trying to make an optical switch circuit.
i'm no expert on electronics, so i was hoping you people could give me a helping hand:)
in advance, thank you very much:)
the purpose of the circuit is to switch an inductive load such as a relay.
when the light is blocked i need the relay to be switched on.
the optical circuit needs a 5vdc supply, and the the relay will be powered by a regulated psu 3-7vdc.
the relay will have a resistance about 3-4ohms.
i also need to keep the switch that turns on the relay open some micro seconds(about 0-0,03seconds) after the light has been cut.
i was thinking that i could hold the switching transistor open with a capacitator and a potentiometer
to regulate how long it would stay open after the light have been cut.
i have looked at this circuit:
http://www.circuit-finder.com/categories/sensor/light-sensor/331/simple-optical-switch
i could use that one, just need to have a adjustable circuit that holds the switching transistor open some micro seconds.
it says 9volt, but the lm555 operates fine with 5volt, so the circuit should work fine with that?
can anybody give me a tipp to how i could make the adjustable switch?
would it be possible to just drop the lm555 chip and hock the switching transistor directly on to the opto switch?
if i could keep the circuit as simpel as possible it would be the best.
so i was thinking that i could just have an opto switch which turns the switching transistor on\off,
and a regulation on the transistor switch which holds it open for some micro seconds.
this is the parts i was thinking of using for the opto switch:
optical transistor: vishay BPW17N, http://docs-europe.electrocomponents.com/webdocs/0de2/0900766b80de2cc1.pdf
IR-diode: vishay CQY37N, http://docs-europe.electrocomponents.com/webdocs/0e22/0900766b80e22c70.pdf
i'm not sure which transistor i should use for the relay switch.
i'm not asking you people to do the work for me.
if you could just give me some advice on what i should check out to figure this circuit out, that would be fine.
then i will draw the circuit and post it. then you could say if it's fine, or point out faults or improvements.
i'm no expert on electronics, so i was hoping you people could give me a helping hand:)
in advance, thank you very much:)
the purpose of the circuit is to switch an inductive load such as a relay.
when the light is blocked i need the relay to be switched on.
the optical circuit needs a 5vdc supply, and the the relay will be powered by a regulated psu 3-7vdc.
the relay will have a resistance about 3-4ohms.
i also need to keep the switch that turns on the relay open some micro seconds(about 0-0,03seconds) after the light has been cut.
i was thinking that i could hold the switching transistor open with a capacitator and a potentiometer
to regulate how long it would stay open after the light have been cut.
i have looked at this circuit:
http://www.circuit-finder.com/categories/sensor/light-sensor/331/simple-optical-switch
i could use that one, just need to have a adjustable circuit that holds the switching transistor open some micro seconds.
it says 9volt, but the lm555 operates fine with 5volt, so the circuit should work fine with that?
can anybody give me a tipp to how i could make the adjustable switch?
would it be possible to just drop the lm555 chip and hock the switching transistor directly on to the opto switch?
if i could keep the circuit as simpel as possible it would be the best.
so i was thinking that i could just have an opto switch which turns the switching transistor on\off,
and a regulation on the transistor switch which holds it open for some micro seconds.
this is the parts i was thinking of using for the opto switch:
optical transistor: vishay BPW17N, http://docs-europe.electrocomponents.com/webdocs/0de2/0900766b80de2cc1.pdf
IR-diode: vishay CQY37N, http://docs-europe.electrocomponents.com/webdocs/0e22/0900766b80e22c70.pdf
i'm not sure which transistor i should use for the relay switch.
i'm not asking you people to do the work for me.
if you could just give me some advice on what i should check out to figure this circuit out, that would be fine.
then i will draw the circuit and post it. then you could say if it's fine, or point out faults or improvements.