Power Research - Jacob-Dixon/MysticWhip GitHub Wiki
##Battery ###First Option Anker Astro Mini
It has a capacity of 3200 mAH which will satisfy the 2 hour battery requirement. It is round and reasonably sized which will allow it to fit in our handle comfortably. It emits 5 V which is ideal for most of the other blocks. The 1A output current exceeds the 900 mA needed for the components. The advantages to using this battery, is a built in charging circuit, as well as emitting 5 V which is what the majority of our project runs on.
###Second Option Aukey mini
The Aukey Mini is very similar to the Anker Astro Mini. Its capacity is smaller, but the maximum output current is greater. Since a battery is not ideal, trusting the capacity to power a 1.5 A system for 2 hours would probably not work. This option would be ideal if the max output current is a little over 1 A thus not being able to run using the Anker Astro.
###Third Option Jackery Bar Portable Charger
This is the worst case scenario option. It will provide more than enough output current if our max output current gets higher than it currently is. It has more than enough capacity to last 2 hours. The reason we are not using it as our first choice is because it is double the price, and is a lot larger than the other options.
##Regulator Selection In my research it came down to two different switching regulators. I chose switching over linear regulators because switching regulators have significantly less power loss than linear regulators. The downsides of switching regulators are the requirement of external components as well as they are more expensive. In the end, the large difference in power loss (over 20%) was reason enough to choose a switching regulator. I compared the two switching regulators to make my decision.
####Pros and Cons of the two switching regulators
| LTC3531 | ISL85415 |
|---|---|
| Costs Less | More Efficient |
| Less External Components | Higher current output |
| Fixed 3.3V output | Larger Voltage Range |
The reason I chose the LTC3531 over the ISL85415was because it was the cheaper option while still satisfying all of my design needs. While the difference between switching and linear regulators in terms of power loss was great, the difference between the two regulators was less than 5%. The Higher Iout was not a benefit either as the only thing running off 3.3 V is the accelerometer.
###First Option LTC3531 200mA Buck-Boost Synchronous DC/DC Converters It can be manipulated to regulate the 5 V down to 3.3 V. It is reasonably priced and does not require that many other components to work the way we want it to. It is more efficient than the alternatives and has a diagram for specifically 5 V.
###Second Option ISL85415 500 mA buck regulator It can be manipulated to regulate the 5 V down to 3.3 V. It is reasonably priced and does not require that many other components to work the way we want it to. It is more efficient than the alternatives and has a diagram for specifically 5 V.
