this post was submitted on 17 Mar 2026
7 points (88.9% liked)

Ask Electronics

4075 readers
1 users here now

For questions about component-level electronic circuits, tools and equipment.

Rules

1: Be nice.

2: Be on-topic (eg: Electronic, not electrical).

3: No commercial stuff, buying, selling or valuations.

4: Be safe.

founded 2 years ago
MODERATORS
DavideAndrea@discuss.tchncs.de
linker3000@discuss.tchncs.de
7
Lenovo USB-C PSU for laptops powers a Rasberry Pi, but cannot simply charge bicycle lights. WTF? (external-content.duckduckgo.com)
submitted 5 days ago by evenwicht@lemmy.sdf.org to c/askelectronics@discuss.tchncs.de
14 comments fedilink hide all child comments
 

I bought a 2nd-hand Lenovo USB-C PSU (ADLX65YLC3D) which indicates a range of voltages (20v, 15v, 9v, 5v) on the label. Tried to charge a few different bicycle lights but the charging indicators did not light up on any of them. I almost tossed it because the 2nd-hand market I bought from is definately dodgy. But then I tried to power a Rasberry Pi and it seems to work on that. So wtf? An a/c adapter either works or it doesn’t. What would cause this: works on some devices but not others? The Rasberry Pi needs 5v just as the bicycle lights. That is the default voltage for USB-c.

you are viewing a single comment's thread
view the rest of the comments
[–] evenwicht@lemmy.sdf.org 1 points 2 days ago

They are actually headlights. The kind that strap to your head, which I happen to use for cycling. I suppose they were intended for joggers. I don’t know the makes but it’s two different manufactures, likely some cheap chinese stuff. One is an LED strip across the forehead with a side beam, 7 or so different functions with different colors and intensities. The other has selectable red, white, or yellow colors, blinking or solid.