- Battery operated and complex devices, like smartphones, tablets, portable PCs, cameras
- USB peripherals, like external hard disks, printers or usb
- No-USB peripherals with <100W power consumption like monitors, toys and gadgets
- Power supply devices like wall chargers, power bricks.
Each category has different needs, requirements and constraints and it’s logic to foreseen for the USB-PD different possible implementations and implications in the system architecture.
Let’s start with the 1st category, the most complex.
Battery Operated Devices
This category includes all the devices with a battery as primary power source and with a USB port used for secondary energy source for battery recharge. This is clearly the most complex device, as it can play as an energy consumer (during internal battery recharge) or as an energy provider (in case, for example, of supplying an external hard disk). I’m clearly referring to Tablets, smartphones and portable PCs. They have already complex power policies and strategies and one or more USB ports for data communication. So not a big issue to integrate a USB-PD feature in such devices. Quite easy from a mechanical point of view, but it’s worth to discuss deeper the possible electronic implementations.