Overkill LEDs and PWMing with electric switch

[Braeden Hamson]

Hey guys,
So I'm building a backlit switch box, in the style of aircraft panels. I bought some LEDs modules without looking at the datasheet...

http://optekinc.com/datasheets/OVM12F3R7.pdf

As you can see they're beefy. I want to PWM these LEDs. I was thinking I'd use a 555 timer chip and configure it to work as a PWM module. I'd then use some kind of electric switch I was thinking a relay or some kind of transistor, to actually switch the LEDs on and off because I know a 555 can't take that kind of voltage. If anyone has a good guide on the different types of transistors (MOSFETS JFETS Bobba Fetts) That'd be greatly appreciated.

 

[Alec_t]

A mechanical relay will be too slow. MOSFETS would be the most practical switching devices.
Different LED colours have different current maxima. Which colour are your LEDs?
How many modules do you plan to combine?
What power supplies do you have?

 

[Bluejets]

These are a logic level switched mosfet which will handle quite a bit of current, they are cheap @ $4.00 odd for 10, plus you can use them in micro circuits as well later on maybe.

FQP30N06L

Look on Ebay.

 

[cjdelphi]

Hey guys,
So I'm building a backlit switch box, in the style of aircraft panels. I bought some LEDs modules without looking at the datasheet...

http://optekinc.com/datasheets/OVM12F3R7.pdf

As you can see they're beefy. I want to PWM these LEDs. I was thinking I'd use a 555 timer chip and configure it to work as a PWM module. I'd then use some kind of electric switch I was thinking a relay or some kind of transistor, to actually switch the LEDs on and off because I know a 555 can't take that kind of voltage. If anyone has a good guide on the different types of transistors (MOSFETS JFETS Bobba Fetts) That'd be greatly appreciated.

Oh i'd love to see a mechanical relay try that, you'd need a SSR / Triac for switching mains...

If not mains use a transistor that can carry the current required

 

[cjdelphi]

0.5w/12v not much power

Any power transistor (npn) and a 500ohm resistor from the 555's pin3 to the base of the transistor. .

 

[hevans1944]

These are a logic level switched mosfet which will handle quite a bit of current, they are cheap @ $4.00 odd for 10, plus you can use them in micro circuits as well later on maybe.

FQP30N06L

Look on Ebay.

Holy cow, @Bluejets! That's one nice little MOSFET! Time to buy a ten-pack of these with free Prime shipping from Amazon to supplement my stock of 2N7000 puppies. You adventurous types can look on eBay for better prices. Here is a link to the Fairchild Semiconductor datasheet. Impressively low on resistance. Thank you Bluejets!

 

[cjdelphi]

Why not use a regular transistor over a fet? They're cheaper

 

[Bluejets]

Holy cow, @Bluejets! That's one nice little MOSFET! Time to buy a ten-pack of these with free Prime shipping from Amazon to supplement my stock of 2N7000 puppies. You adventurous types can look on eBay for better prices. Here is a link to the Fairchild Semiconductor datasheet. Impressively low on resistance. Thank you Bluejets!

No worries mate...glad it helps....