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Topic: light sensor circuit (Read 991 times) previous topic - next topic

adivinorum

i want a bulb/led to light up with an intensity dependent upon the amount of light that hits the analogue light sensor...do i really need arduino or any programming? , or can i just connect the battery ,the light sensor and the bulb in a simple circuit??

dhenry

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do i really need arduino or any programming?


A 555 + photoresistor will do that for you.

Grumpy_Mike

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can i just connect the battery ,the light sensor and the bulb in a simple circuit?

Yes you can but the components will have to be exactly the right type to get everything balanced. For example if you use a light dependent resistor you need to make sure that it can take the current and that the fully lit resistance is sufficient to turn your light on. I have done this sort of thing in the past and I have also use a relay directly connected to a light dependent resistor. I was able to use the normally closed contacts to light a flash light bulb that dropped the resistance of the light dependent resistor, thus turning it on, breaking the contact, turning the bulb off which robbed the sensor of light, turned the relay off thus turning the bulb on again. This made a simple oscillator.

dhenry

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if you use a light dependent resistor you need to make sure that it can take the current


What "the current" are you talking about?

Grumpy_Mike

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What "the current" are you talking about?

The current that it will pass in what ever circuit arrangement you end up with.

dhenry

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The current that it will pass in what ever circuit arrangement you end up with.


When was the last time you have used a photoresistor that cannot take the current going through it?

Grumpy_Mike

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When was the last time you have used a photoresistor that cannot take the current going through it?

Back in 1965, have you never used these?

dhenry

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Back in 1965,


Maybe it is time for an update on modern photoresistors?

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have you never used these?


I have never used a 1965's photoresistors.

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