How to Convert USB Host Mini Board to 5V



The USB host mini board is ideal to use with 3.3V logic systems such as ARM and ESP boards. However, it defaults to 3.3V on the USB host connector power pin (VUSB). Some USB devices work with 3.3V power but many do not. Fortunately, the board is designed to be modified.

In the photo, the red line shows the trace to cut. This must be done to disconnect VUSB from the 3.3V power rail. The red wire connects VUSB to another power source. On this board, the red wire is connected to a Lithium battery. The USB spec requires 5V but my small collection of USB devices work when powered by the battery. If your USB device needs 5V, power the system using a USB power bank usually used to recharge cell phones. USB power banks output 5V and come in a wide variety of sizes.

This change does not change the digital logic levels on the data pins. The board remains compatible with 3.3V boards. The only change is to the voltage output on the USB connector.

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