The following excerpt of the research results shows a selection of devices which provide… A summary of the the specification of the most interesting solutions are shown in table 1.
The Voltwerks VW1-U by Revely Microsystems shown in figure 1 is a laboratory power-supply with a maximum output range of 0.8 V to 10.2 V.
The actual voltage range and maximum output current is limited by the used power source. In comparison to the OpenLab UI-Source, the output voltage of the VW1- U is restricted to a maximum of 4.5 V using a 5 V power supply. The OpenLab tool is able to generate up to 12 V by utilizing a standard USB power source. On the other hand, the OpenLab UI-source is limited, by design, to the maximum output specifications of the USB port. The output voltage of the VW1-U can be controlled by adjusting a small potentiometer on the front of the device. This laboratory power-supply is closed source and available for 59.00 dollars.
The VariPower-USB-500A by Etonnet LLC shown in figure 2 is a USB powered variable power supply with a maximum output range of 1.2 to 4.8 V.
The actual output current is up to 500 mA with a USB cable connection to a computer but can be increased to 2.0 A if the external USB AC / DC adapter is used. The reason for the tiny product is that it is cheaper for the customer and easier to travel with it. This mini power-supply is available for 36.95 dollars.
Revely Microsystems, Voltwerks VW1-U [Online] http://www.revely.com/voltwerks/power
Etonnet LLC, VariPower-USB-500A [Online] http://www.etonnet.com/products.aspx
electronic-lab.com: AMPSTRIKE - BATTERY POWERED BENCH POWER SUPPLY [Online] http://www.electronics-lab.com/ampstrike-battery-powered-bench-power-supply/
CNXSoft - Embedded Systems News: USBminiPower USB Power Supply Delivers 3 Outputs: 5V, 3.3V, and a Variable Output up to 14.3V (Crowdfunding) [Online] https://www.cnx-software.com/2015/04/29/usbminipower-usb-power-supply-delivers-3-outputs-5v-3-3v-and-a-variable-output-up-to-14-3v-crowdfunding/