I am working on a IoT project that involves an arduino and a 4G LTE module. The device will be operated with two Alkaline batteries. Both the arduino and LTE module require 3.3V input so I want to design a boost converter that reliably delivers 3.3V from a voltage range of 1.6 to 3.1. The device will be in a deep sleep for most of the day and only wake up 2-3 times a day for a short period of time, so an important converter requirement is low quiescent current. While the arduino doesn't draw much current (50mA-100mA), the LTE module requires up to 1.2A of current when awake.
Doing my research for suitable boost converters, I came across the TPS613221ADBVR. It has low quiescent current (6.5µA) and can provide up to 1.6A of current. But given my limited knowledge in electrical circuits, I'm a bit overwhelmed when it comes to choosing the right inductors and capacitors. The datasheet is excellent and gives two examples on how to choose inductor/capacitor for the given requirements of 2.2V output @ 50mA (example 1) and 5V output @ 500mA (example 2).
The requirements in my case are as follows:
- Input Voltage: 1.6V ~ 3.1V
- Output Voltage: 3.3V
- Output Current: 1.2A
- Output Voltage Ripple: ?? (how to find out?)
What inductors and capacitors do I choose? Do I need a Schottky Diode and if so, which one? What Output Voltage Ripple can be tolerated?