Hi everyone,
A project I'm working on needs to have a circuit that will, when powered up, take input from a light sensor, and switch a relay once the light has dropped below a certain threshold. I've come up with a schematic diagram of what I think will work, and preliminary work on a breadboard suggests that it is functional, but I wanted to get some opinions on potential problem spots.
There are some superfluous details in the schematic, such as the jumper connections to a couple of switches, but the real meat of the circuit consists of a photodiode (PD1), resistors, a CD4066, and a DPDT relay. It's for an automotive application (necessitating the relay and the 7805).
Please let me know of any ways that this circuit could be made more robust. However, it is an absolute requirement that the relay is in the same state in daylight as when there is no power to the circuit.
Thanks for any and all help!
jptrsn
[EDIT] I forgot to mention that I've assembled this from salvaged parts, which is why I have such a strange assortment of pieces. That's another of the goals of the project - recycling discarded e-waste.
A project I'm working on needs to have a circuit that will, when powered up, take input from a light sensor, and switch a relay once the light has dropped below a certain threshold. I've come up with a schematic diagram of what I think will work, and preliminary work on a breadboard suggests that it is functional, but I wanted to get some opinions on potential problem spots.
There are some superfluous details in the schematic, such as the jumper connections to a couple of switches, but the real meat of the circuit consists of a photodiode (PD1), resistors, a CD4066, and a DPDT relay. It's for an automotive application (necessitating the relay and the 7805).
Please let me know of any ways that this circuit could be made more robust. However, it is an absolute requirement that the relay is in the same state in daylight as when there is no power to the circuit.
Thanks for any and all help!
jptrsn
[EDIT] I forgot to mention that I've assembled this from salvaged parts, which is why I have such a strange assortment of pieces. That's another of the goals of the project - recycling discarded e-waste.
Last edited: