I’m reading 4.36v on the Li+ pin of my Argon when connected to USB power (via the microusb socket). Can I draw current from this to power peripherals?
I won’t recommend it. The device is attempting to charge a LiPo battery. It’s not intended to be used as a power rail.
Use VUSB if you need 5V or the 3V3 pin for 3V
Sure. The reason I was attempting to is that I’m working on a product that may be powered from either USB or LiPo, so access to a pin that’s always ~3.8v or higher would be kinda useful.