Hi, this is a simple one, and I can imagine you answered it in a million forms but before I do anything irreversible I thought I'll ask.
Is it possible to use an usb mobile phone charger to be used as an extra power supply for the mux board? The case is the following: - JP7 and JP6 is wire 1:1 meaning all the subchannels are going to be powered using the computer side pins as source - the J1 grove connector is used to hook the mux board to the base i2c bus - the end of the usb cable is cut off and the VCC, GND wires connected to JP1 3,4 respectively - computer side pins
The real question is: Can I just simply connect that external power source as I described to the JP1 pins and that's it? I don't want to fry the board considering the mux board is already getting power through the grove connector. On the other hand the setup "feels" comfortable and purposeful.
I was waiting for nearly two months for the board to arrive, my favorite and central component, and I'm more like a software guy. Gimme a go!
You are connecting VCC from the main computer (through the Grove connector) and also from JP1. Those two pins are connected together, so you are supplying VCC from two different places. Take an Ohm meter and you can verify this. Depending on your power supplies, this can be a problem. Not a good thing to do generally.
If you are going to do this, cut the red line on the Grove cable so you are only getting VCC from one place (which after cutting, it would be from your USB cable).