Circuit Diagram

This provides a visual reference for the wiring of the components. They aren't true to scale, just meant to be used as reference. 

To power this circuit, we'll use a 3.7v 2500mAh lipo battery. The PowerBoost has an on board regulator that will convert the voltage to 5V automatically. It also has on-board charging circuit, so we can recharge it over USB when the battery gets low.

• Ground from PowerBoost to Switch
• Enable from PowerBoost to Switch
• 5V from PowerBoost to 5V on TFP401
• Ground from PowerBoost to ground on TFP401
• Battery to JST connector on PowerBoost