I’m designing an LED strip controller including the Spark. When I’ve done something similar from an Arduino I’ve taken the 12v PSU and split off a channel via a 7805 to power the Arduino via the same PSU as the LED strip.
As the Spark runs at 3.3v, I don’t like the thought of the heat a regulator (e.g. LM1117T) would put out to drop from 12v.
I’m thinking of sticking with the 7805 (or a UBEC but they’re a bit big) and using that as input to the VIN/RAW pin1 which I understand has a 3.3v regulator that can take up to 6v as input and output 3.3v on VCC (what’s 3.3v with the dot?) what i don’t like about that is that all my current would have to flow through the Spark, esentially the Spark is an expensive 5v-3.3v regulator!
I’m going to use 3 STP16NF06L logic level MOSFETs to control the PWM signal to the LED strip RGB channels, but other than that, there’s not going to be [m]any other components, maybe an LDR or PIR or capacitive touch sensor.
What are the power requirements of the Spark when using wifi - 350mA max. I think i saw somewhere? As I could use one of these 600mA or these 500mA Pololu bucks if I can keep current consumption down. Oooh, the TSR 1-2433’s look quite nice at 1A too…
I don’t want to use USB power or a shield or a breadboard PSU or anything so big as one of those LM2596 boards you get on ebay. So what kind of thing are people doing to get 3.3v?
The alternative is to switch to WS2182 LED strips which can run from a 5v PSU which is easier to regulate, but I’ve already got 5m of analogue 12v strip which is cheaper than 1m of digital.