Hello Hardware experts,
I’m planing to build a (LiPo) battery powered ultrasonic sensor project controlled by one of my Photons.
The challenge here is, the ultrasonic sensor (HC-SR04) requires 5 volts. I testet it with an USB powered Photon which work fine.
But the final project will have the Photon is powered by a Sparkfun battery shield. Measurements taken once an hour, the rest of the time the Photon is going to deep sleep.
My questions is about the options, best practices to power the sensor with 5 volts. Especially in combination with only 3.7 volts from the LiPo and with the goal of maximum energy efficiency. If the Photon is in deep sleep the sensor should be without power to conserve energy.
Currently I have the following idea, but not sure if they might work at all:
- use a 5V Step-Up module (like https://www.sparkfun.com/products/10968) connected to the 3.3 Vout of the Photon power the sensor
- use a 5V Step-Up module (like https://www.sparkfun.com/products/10968) connected to one of the Dx pins of the Photon and set that to HIGH to have full control about the sensor power
- Power the sensor with a separated battery (4 Eneloop AA can give 4.8 volts) and use a relay to switch power on / off
- Power the entire system Photon & sensor by 4 Eneloop AA batteries
- Power the entire system Photon & sensor by USB Powerpack
Are the other options as well? Any help is appreciated.