anderscrib:
I am trying to control some LED strip lights (12V, 2 AMP) with the arduino and am trying to select the correct MOSFET to handle the load. I thought this one (http://www.vishay.com/docs/91325/sihlz14.pdf) might work but it does not. When connected with all the pull down and limiting resistors, the lights are dim. Then I noticed when I connected the Drain to Source without the gate power was getting through and dimly lighting the lights...I have researched several sites and similar projects but they do not have the same conditions.
Any thoughts? Thanks community!
That MOSFET has a rather high Rds(on) of 0.2 ohms, so it will dissipate 800mW for a 2A load - it will run very hot - small heatsink highly recommended. Its perfectly upto the job though as it is logic level and will only lose you 0.4V in voltage drop - clearly you have it wired up wrongly.
If you connect drain to source then you completely bypass the device, and if in that state the LEDs aren't lighting up properly its clearly nothing to do the the MOSFET!