I’m learning more about capacitors on 3.3V regulators, how they’re used, and the effect of ESR on efficiency and ripple current.
Can you tell what type of capacitor is on the Pololu 3.3V regulator?
And can you comment on the quality of this capacitor in hot or cold tempeatures? Or how efficient it is?
If I made my own 3.3V regulator circuit from any of the number of TI or Maxim chips, is it just the output capacitor that I have to worry about ESR and be more picky with? Can the input capacitors be the $0.01 ceramic disc or electrolytic capacitors I already have a lot of? This is for an outdoor application, so summer temperatures get up to 110F and winter gets down to -10F. Maybe put two capacitors in parallel to improve ESR?
This regulator will be used for to power the ATMEGA328 chip as well as the wireless nRF24L01 module, in a battery application. So energy efficiency is a concern. I’m on the fence about whether I should just get the Pololu or try to make my own 3.3V power circuit. The Pololu lists typical quiescent currents less than 100uA (that’s .1mA right). The Maxim 756 chips list Iq somewhere in the 60uA, but maybe if I use commonly available parts, I’m making compromises that increase Iq anyways and I might as well buy the Pololu at $6 each. The Pololu is designed by people who know what they’re doing, where as I might just be using what’s on hand.