I am trying to power the TTGO LoRa32 using a power adapter of 5V since I want to use the device with a HC-SR04 ultrasonic sensor that needs a power supply of 5V for the board. Since the micro usb port does not provide enough power to start the sensor. Does anyone know the appropriate power rating for the LoRa32 device? Which one of the following would be appropriate : 5V-1A, 5V-1.2A, 5V-1.5A, 5V-2A(…so on)?
I cannot seem to find the information on the website. Appreciate if anyone can assist me with this!
Well there seems to be no mention of supporting ‘power delivery’ so almost by default the micro USB connection, specifications limited to 500mA.
It might be worth investing in a small USB Power Meter device. Very cheap these days.
That been said found a schemaitc
looks to use 2 me6211 regularors, which can supply 500mA each at 3.3V. Suggests they need more than 500mA at 3.3V (to warrant two!).
So each regulator could transfer upto 1.65W, so 3.3W. Thats 0.66A at 5V. Which is probably pushing the USB spec too far.
So a 1A (at 5V) might be safest. Seems the Ultrasonic sensor itself uses 15mA at 5V.