i have been working on this project for a month. but i keep burning out my diodes.
my project is a photo switch using a 5mw laser as the light source. the photoswitch circuit works great and the laser activates it just fine. But i cant get my lasers to stop dyeing. first i replaced the button batteries with a 4.5 v power supply. as i am sure you all know that doesnt work. so then i researched and found out i needed about 3v. so i built a constant voltage power supply using an adjustable LM317 voltage regulator. that didnt work. more research so i built a constant current supply also using an LM317. well that didnt work. my project also uses a relay in it so i thought i was getting a spike off the coil when the coil is denergized so i put a reverse biased diode across the coil leads. well the diode ran for 24 hours, then i switched the relay on and off a bunch of times and still all was fine. then i left it on for another hour came back and the laser was a very weak glow again anybody have any ideas what i am doing wrong. i am out of things to try
my project is a photo switch using a 5mw laser as the light source. the photoswitch circuit works great and the laser activates it just fine. But i cant get my lasers to stop dyeing. first i replaced the button batteries with a 4.5 v power supply. as i am sure you all know that doesnt work. so then i researched and found out i needed about 3v. so i built a constant voltage power supply using an adjustable LM317 voltage regulator. that didnt work. more research so i built a constant current supply also using an LM317. well that didnt work. my project also uses a relay in it so i thought i was getting a spike off the coil when the coil is denergized so i put a reverse biased diode across the coil leads. well the diode ran for 24 hours, then i switched the relay on and off a bunch of times and still all was fine. then i left it on for another hour came back and the laser was a very weak glow again anybody have any ideas what i am doing wrong. i am out of things to try