Doc,
Ok, after reading what you said here, I'm starting to thinking the BSS1338 would work for me, (and I have them already). So, after reading a few wikis about MOSFETS, transistors, gates, sources, and drains, I've determined I will never fully understand this stuff!
Here's what my project is sizing up to be like: an ATtiny85 (programmed from an UNO). One sensor on a pin, and three output pins. Each output will. Have (3) Super bright LEDs like this:
They draw a max current of 20mA, so I'll probably run them around 15mA. So that's 45mA I need to switch. The datasheet for the ATtiny85 says 40 mA per I/O pin (and that's max, not typical), so I better use something to switch them.
You said the BSS1338 would work perfect for 3.3 volts... I could have my project work off a 3.3 volt SMD LM1117, since my maxbotix sensor will work at that voltage. So, do I connect the ATtiny85's output pins directly to the BSS1338? --like this?
Gate: ATTiny output pin
Source: Gnd
Drain: Cathode of the LEDs
...so I don't need any resistors between the output pins and the BS1338?
Thanks again.