Heavy Load Switching with CodeBug

Has anyone tried switching slightly heavier loads using the CodeBug's legs, either using a transistor or a relay? I'm working on something that'll need to switch two loads on and off that I'm pretty sure would melt the CodeBug if I did it directly (maybe 1-2 amps each). I'm thinking that something as simple as a transistor, switched from one of the legs, would do the job, but thought I'd ask if anyone's experimented this as yet?

Top Replies

Parents

0 shabaz over 9 years ago

The 'GPIO Explained' schematic with the transistor and relay should work too.
(For some reason the editor is mangling the URL - will raise a feedback & support request. Circuit is below):

(Finder 32.21.7.005.2000Finder 32.21.7.005.2000 is a convenient relay for up to 6A, fits stripboard nicely).
Or a MOSFET based circuit, but I left them out of GPIO Explained due to opportunities to go wrong if people attempt to use alternatives!),
Cancel
Vote Up +4 Vote Down

Sign in to reply

Verify Answer

Cancel
0 spannerspencer over 9 years ago in reply to shabaz

Excellent suggestion, Shabaz, and I'm now wondering whether to go with Jon's MOSFET option, or whether to get a double pole relay and switch both loads from just one of the CodeBug's legs. Although I may need to control them separately... I'll have to think about that some more

Either way, always appreciate the ideas from all your guys!
Cancel
Vote Up +1 Vote Down

Sign in to reply

Verify Answer

Cancel
0 shabaz over 9 years ago in reply to spannerspencer

Hi Spanner,

Personally I'd go with Jon's suggestion for my own boards, only caveat is that it is a surface mount device which not everyone is comfortable with. If you're using a relay, then you may as well use the NPN method, since it doesn't care what specific NPN transistor you use.
But yes, many ways to swing a cat : )
Cancel
Vote Up +1 Vote Down

Sign in to reply

Verify Answer

Cancel

Reply

0 shabaz over 9 years ago in reply to spannerspencer

Hi Spanner,

Personally I'd go with Jon's suggestion for my own boards, only caveat is that it is a surface mount device which not everyone is comfortable with. If you're using a relay, then you may as well use the NPN method, since it doesn't care what specific NPN transistor you use.
But yes, many ways to swing a cat : )
Cancel
Vote Up +1 Vote Down

Sign in to reply

Verify Answer

Cancel

Children

0 jc2048 over 9 years ago in reply to shabaz

Absolutely. And there may be real advantages to having the isolation that the relay gives; without knowing a bit more about what "Spanner Spencer" is trying to do it's difficult to say.

The bipolar transistor is much more robust handling-wise, too, particularly if poeple aren't used to electronics and don't understand about the possibility of static damage.

Soldering an SOT23 is quite easy, though. They're probably the easiest SMD parts to prototype with (at least I can see the things, which isn't the case with some of the surface mount resistors you can get now).
Cancel
Vote Up +1 Vote Down

Sign in to reply

Verify Answer

Cancel