Author Topic: Mounting LED's (Read 489 times)

G7PSK · « **on:** February 04, 2021, 04:15:25 pm »

I am making an 8mm cine film scanner and going to use an LED for light source. There is not a lot of room for a heat sink so I am going to solder it directly to a chunk of copper. The thing is would it be better to solder the positive or negative to the copper as well or isolate both junctions.

ajb · « **Reply #1 on:** February 04, 2021, 10:37:21 pm »

Assuming you're referring to soldering an electrically isolated thermal pad to the copper, there's no electrical benefit to soldering either electrical contact onto the heatsink. There might be a mild thermal benefit, but it's probably insignificant compared to getting the thermal pad soldered down. If you're using an isolated LED then it really doesn't matter, but if the driver is not isolated you're probably better off not making an electrical connection to the heatsink at all (except possibly connecting it to chassis ground if you have such a think in your device).