This is probably a total noob question, but how do I step down to 1.2V? [This module seems to do 3.3->5 or 5->3.3. It also mentions it can do 2.8 and 1.8. What do I need to step down to 1.2V? I ask because the WiFly sensor pins are supposed to be no more than 1.2V.](http://www.sparkfun.com/products/8745)
From 3.3 you can drop 2.1V with this led: http://www.sparkfun.com/products/532 or similar one. Do not forget to limit current!
What are you actually trying to do? A schematic or similar would help. Often you can just use a simple resistive voltage divider in these types of situations.
Lol. Amusing that I was so overthinking it. I was looking for some complicated solution.
I can’t post my plan right now (I’m with my toddler) but I’ll explain better later in case someone has an optimal solution for me.
Ok so the WiFly BoB ( http://www.sparkfun.com/datasheets/Wire … ut-v13.pdf ) will be hooked up to an mbed ( http://mbed.org/handbook/mbed-NXP-LPC1768 ) for the most part, but the sense pins on the WiFly require 1.2V MAX. I don’t yet have any specific use in mind for these pins but I’m sure I will soon enough.
OK, the “sense” pins on the WiFly are 14-bit ADC (analog) inputs with a full-scale voltage of 400mV and an Absolute Maximum voltage of 1.2V.
Sense 0-3 pins also have a “wake up” feature where they wake up the module when the voltage exceeds 500mV (but note the 1.2V max). This is shown on page 4 of the datasheet, where a voltage divider is used on the SENS0 pin to provide a means of waking up the module. I suggest you do something similar.
As for the other “sense” pins, you could use these if you have analog voltages you want to measure for your application. Make sure you scale the voltage to no more than 400mV max. Normally you would just use the ADC inputs on your host CPU (ie, the mbed module), but this could be handy if you didn’t have any ADC inputs available.