light sensor using LDR and LM741 - Electronic Circuits Projects Diagrams Free

siau2 · 17th December 2003, 07:31 AM

Hi,

I want to build a light sensor and here is what I think. The LDR and variable resistor will make a voltage divider, then the output voltage will be connected to LM741 for signal amplifying. Will this simple circuit work? I need to amplify the signal since it has to be in the range between 0-5V to go in ADC. The other thing is whether it's possible to make LM741 operates using single source only, since I don't think this can be done by simply grounding the negative supply. Hope I could get some advice.

Sebi · 17th December 2003, 04:34 PM

The 741 output can't go to 0V, choose a rail-to-rail type op-amp.

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17th December 2003, 07:31 AM	(permalink)
siau2	light sensor using LDR and LM741 Hi, I want to build a light sensor and here is what I think. The LDR and variable resistor will make a voltage divider, then the output voltage will be connected to LM741 for signal amplifying. Will this simple circuit work? I need to amplify the signal since it has to be in the range between 0-5V to go in ADC. The other thing is whether it's possible to make LM741 operates using single source only, since I don't think this can be done by simply grounding the negative supply. Hope I could get some advice.

17th December 2003, 04:34 PM	(permalink)
Sebi	The 741 output can't go to 0V, choose a rail-to-rail type op-amp.