Communities

Writing
Writing
Codidact Meta
Codidact Meta
The Great Outdoors
The Great Outdoors
Photography & Video
Photography & Video
Scientific Speculation
Scientific Speculation
Cooking
Cooking
Electrical Engineering
Electrical Engineering
Judaism
Judaism
Languages & Linguistics
Languages & Linguistics
Software Development
Software Development
Mathematics
Mathematics
Christianity
Christianity
Code Golf
Code Golf
Music
Music
Physics
Physics
Linux Systems
Linux Systems
Power Users
Power Users
Tabletop RPGs
Tabletop RPGs
Community Proposals
Community Proposals
tag:snake search within a tag
answers:0 unanswered questions
user:xxxx search by author id
score:0.5 posts with 0.5+ score
"snake oil" exact phrase
votes:4 posts with 4+ votes
created:<1w created < 1 week ago
post_type:xxxx type of post
Search help
Notifications
Mark all as read See all your notifications »
Users Search
Help Dashboard Sign In Sign Up
Q&A Papers Meta
Q&A
Posts Tags Edits
Ask Question

Post History

50%
+0 −0
Q&A Driving LED with NPN transistor from I/O pin

I have tried to drive a series of smd led with constant current. If it is rated for 3.3V, I run it at around 3V. It doesnt get hot even without a heatsink, ~60C. So thermal runaway is only a proble...

posted 4y ago by timelyfiasco‭

Answer
#1: Initial revision by user avatar timelyfiasco‭ · 2020-08-05T07:33:38Z (over 4 years ago) 
I have tried to drive a series of smd led with constant current. If it is rated for 3.3V, I run it at around 3V. It doesnt get hot even without a heatsink, ~60C. So thermal runaway is only a problem under extreme and unlikely circumstance. This also results to higher power efficiency theoretically.
This is a more cost effective solution than using a CC source and heat sink. But if you include the time to solder hundreds of smd...
What could be the downside of this approach that it is not popular?