CMOS Toggle Flip Flop Using Laser Pointer circuit

The IR photo transistor Q1 (Radio Shack 276-145A) or a similar component is connected to the set input (pin 6). It is essential to shield the photo transistor from direct light to ensure that the voltage at the set input (pin 6) remains below 1 volt under ambient conditions. When illuminated by a laser pointer or another light source, the voltage should exceed 1 volt.

The IR photo transistor Q1 serves as a critical component in the circuit, functioning as a light-sensitive switch. When the circuit is designed, it is important to position the photo transistor in a manner that minimizes exposure to ambient light. This can be achieved by using a housing or cover that blocks unintended light sources while allowing the desired laser light to reach the sensor.

In operation, under normal lighting conditions, the photo transistor will maintain a low output voltage at pin 6, indicating that it is in a non-conductive state. This low voltage is crucial for ensuring that any subsequent components in the circuit, such as microcontrollers or logic gates, interpret the signal correctly as an "off" state.

Upon exposure to a laser pointer or a similar light source, the photo transistor becomes conductive, allowing current to flow and causing the voltage at pin 6 to rise above 1 volt. This transition can be utilized to trigger other functions in the circuit, such as activating an alarm, turning on an LED, or sending a signal to a microcontroller for further processing.

To enhance the performance of the circuit, it may be beneficial to include additional components such as resistors for current limiting and capacitors for filtering. The choice of these components will depend on the specific requirements of the application, including the desired response time and sensitivity of the photo transistor to different light wavelengths. Proper calibration and testing will ensure that the circuit operates reliably under various lighting conditions.The IR photo transistor Q1 (Radio Shack 276-145A) or similar is connected to the set input (pin 6). The photo transistor should be shielded from direct light so that the voltage at the set input (pin 6) is less than 1 volt under ambient conditions and moves to more than volts when illuminated by the laser pointer or other light source.. 🔗 External reference