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https://www.circuitlab.com/circuit/8ap48tu36huk/light-sensor-help/

(First time asking a question on this site so I put everything in my circuit description)

Thank you in advance.

The OpAmp is used as a comparator, producing a positive or negative voltage (the voltage supplied to the OpAmp IC, sometimes labeled Vss and Vee) , less the rail offsets of the chosen OpAmp) in its output if the voltage at its input+ pin is less or more than 2Volt (2V being, here, the voltage at its input- pin ). (If the voltage at its input+ pin is close to 2V, the output voltage is technically undefined, because it is subjected to the variations in its fabrication).

I don't see any "question" in the circuit.

This is the question, in question. I am currently doing a school project where we are tasked to build a circuit that will be turned into a PCB. The circuit needs to be comprised of at least three components to be considered complex enough, in which I only have two. The current circuit is built with an LDR voltage divider and a comparator.

The LDR resistance ranges from 50ohms in direct LED light, to 19Mohms in darkness, with ambient classroom resistance at 1.2kohms. The R1 value was chosen at 200ohms so that the output1 voltage ranges from 1V to 5V (4V peak to peak) respectively. The comparator (TL074) is powered with +/-12V with a 2V offset.

Any help to add another component to the block diagram would be greatly appreciated.

| LDR voltage divider | -> | Comparator |

(Vcc) ---+ | [PIR Sensor] | +----->|---- [1kΩ] ----> B (Base of Transistor) | | | C (Collector) | | GND [LED] ---> [220Ω] ---> Vcc | E (Emitter) | GND

Nice

Have fun with slope game