Hi.
I have an LED Driver that's rated for 6.8-12vdc 600ma. Can I power my arduino with it? My understanding is that LED Drivers are constant current, where most normal wall warts are constant voltage.
I want to use the LED driver because it's liquid tight, cheap and actually seems to be made well. Nice aluminum housing too.
Thanks!
Can I power my arduino with it?
No.
Well if you connect it to Vin you might get away with it because the arduino has it's own voltage regulator.
clearchris:
I have an LED Driver that's rated for 6.8-12vdc 600ma. Can I power my arduino with it?
The driver will keep increasing the voltage until there's 600mA flowing through the device. It might stop at 12V, it might go a bit higher than that.
An Arduino is only rated to 12V.
You might get lucky ... but you risk the Arduino's voltage regulator overheating.
You could do a quick test and see what happens. Put your finger on the Arduino's voltage regulator and switch it on. If it burns your finger, it's a bad idea to keep using it. 
Yes, technically you can.
wire LED Driver with shunt regulator/parallel voltage regulator and Arduino.
simple sample: 1N5338 5W/5V zener, most power consumer at shunt regulator and convert to heat.
This setup is not environment green and do not recommend.
might use 1N5343 5W/7.5v zener, since 1N5338 might push too hard and leave 2.5v to Arduino's voltage regulator.
sonnyyu:
Yes, technically you can.
But is it a good idea?
If it was me, I wouldn't.
You probably need to attach some other stuff to the Arduino as well (what use is an Arduino with nothing attached?). Running everything through the tiny Arduino regulator with 12V input is bound to overload it. It's not worth it for a $6 power supply.
You probably need to attach some other stuff to the Arduino as well (what use is an Arduino with nothing attached?).
shunt regulator/parallel voltage regulator attach to the Arduino, Arduino voltage regulator get 7.5 v as input.
Anyone have a recommendation for a solid power supply? I have been having a bunch of wall warts fry on me lately.
This one will be exposed to cold (32-40F, 0-14C) and possibly moisture.
iPhone 4S Tech Specs
Operating temperature: 32° to 95° F (0° to 35° C)
Nonoperating temperature: -4° to 113° F (-20° to 45° C)
Relative humidity: 5% to 95% noncondensing
Maximum operating altitude: 10,000 feet (3000 m)
Since iPhone power adptor is accessories of iPhone 4S, It has to meet the specs
noncondensing
They all say that, most outdone moisture is.
I looked on eBay for something but all the "outdoor" power supplies seem to be either:
a) Very expensive
or
b) LED drivers.
A wall-wart can probably be weatherproofed with some liberal application of hot glue and/or a project box. You could even get a pretty aluminum project box to house it.
Unless you plan on submerging it, a plastic box and plenty of glue to seal any gaps?
fungus:
I looked on eBay for something but all the "outdoor" power supplies seem to be either:
a) Very expensive
or
b) LED drivers.
Good found!
Plan B for LED driver.
Since 1N5343 5W/7.5v zener is not popular part in tool box. Here is substitute. 10 pcs IN4001/IN400X SILICON RECTIFIER in serial, the forward drop voltage is 0.7~0.8 v for each, 10 pcs will make 7~8 v. attach to the Arduino, Arduino voltage regulator get 7~8 v as input.
Solder them in serial and put it into heat shrink tube.
Plan C.
Leave LED in place, attach to the Arduino to LED. Now we have free light for Arduino.
Do we need Plan D? if any one think so I will keep working. 
Plan D ios combinations of LED's and Diodes... Good Work, Dude... BUT remember the Max current for the LED and choose an LED of the right current capacity..
Bob
Docedison:
Plan D ios combinations of LED's and Diodes...
Good try.
Plan E.
Use 2 pcs 5V/5W TVS (TRANSIENT VOLTAGE SUPPRESSOR) diode, serial them together and attach to the Arduino, Arduino voltage regulator get 10 V as input. 5V TVS is widely use by PC, instrument power supply. make sure it has Steady State Power Dissipation 5W, not Peak Pulse Power Dissipation could be thousands W.
TVS<>Zener
TVS’s are designed, specified and tested for transient voltage protection, while a Zener diode is designed and
specified for voltage regulation.