1. Light Detection Circuit
EE40 Final Project
Light Detection Circuit

2. Project Summary
Light-sensing circuit; When there is no light shining on the detection part of the circuit, the green LED flashes. At the presence of light, the red LED flashes instead of the green one.
Possible application:…..
Possible improvements:………

3. Supply Circuit
Purpose: powers the circuit components by generating two different voltages from a single input voltage
Input: 9V
Output: 4.5V and 9V
Comments: The op-amp act as a voltage follower that outputs 4.5V. 9V
4.5 V

4. Square Wave Oscillator
Purpose: Generates 0-9V square wave signal that makes the LED’s flash.
Input: 4.5V and 9V
Output: 0 or 9V
4.5 V
9 V

5. Light Detection Purpose: detects light Input: 4.5V Output: 0 or 4.5V

6. Comparator
Purpose: compares the output of the light detector with the threshold
Input: 4.5V and 9V
Output: 0 or 9V
4.5 V 9V

7. AND Gate 9V
Purpose: To control the flashing of the red LED based on the MOSFET’s drain

8. Bonus circuit examples: VU Meter
500k