David Johnson-Davies' Power Deliverer Turns a USB Type-C PD Brick Into a Configurable PSU
Enabling quick selection of any USB Power Delivery profile supported by your charger, the Power Deliverer does as promised.
Embedded developer and hardware engineer David Johnson-Davies has unveiled a new tool designed for anyone experimenting with USB Type-C power supplies for their future projects: the Power Deliverer.
"This board allows you to use a USB-C power adapter as a power supply with a range of fixed voltages," Johnson-Davies explains of the Power Deliverer. "It displays a list of the voltages and currents available from the adapter and allows you to select one."
The compact board is designed around an STMicroelectronics STUSB4500 standalone USB Power Delivery (PD) controller, linked to a Microchip ATtiny1604, which provides the user interface via on-board buttons and a compact 128×32 OLED display panel.
"When you connect my Power Deliverer board to a USB-C charger with Power Delivery it displays a menu of the available voltages and their current capabilities, up to a maximum of 20V at 5A," Johnson-Davies explains. "Each voltage/current option is referred to as a power profile. You can highlight one with the cursor, and then pressing the Select button will select this voltage on the output terminals, and the display shows the currently selected power profile."
Those output terminals are found on the opposite side of the board to the USB input, using screw terminals to make wiring easy yet secure. An on-board LED indicates that a profile has been selected and the output terminals are energized, with the selected voltage and amperage displayed on-screen.
There is only one real catch with the design: It is specifically centered on the USB Power Delivery standard, and won't work with non-PD power supplies; instead, the display will show "NO PD" to indicate it received no response to its query for supported power profiles.
"This project is only intended for hobby use, and is not an end-user product," Johnson-Davies warns. "I haven't tested it to make sure that it meets any regulatory requirements, including interference and safety, and it's possible that a programming fault could potentially cause it to output a higher voltage than selected. Please do not use it to power expensive equipment!"
Full details on the board are available on Johnson-Davies' blog, along with a schematic and source code for firmware based on Arduino Wire and Johnson-Davies' own TinyI2C libraries; Eagle PCB design files are available on GitHub under an unspecified open source license.